Metal fiber filter, filter unit and gasifier

Abstract

Provided is a metal fiber filter or the like capable of suppressing fluid retention at the end of a filter medium. This metal fiber filter (1) is provided with: a cylindrical support body (2) having a first end (E1); a filter medium (3) disposed on the outside in the radial direction of the support body (2); and a first end member (4) affixed to the first end (E1) side of the support body (2). The support body (2) includes: a first support section (11) having a first outer diameter (D1); and a second support part (12) which is located on the first end (E1) side of the first support part (11) and has a second outer diameter (D2) that is larger than the first outer diameter (D1). A plurality of through-holes (11a) are formed in the first support section (11). The filter medium (3) is a sintered body of metal fibers, and includes: a medium body (30) that is disposed on the outside in the radial direction of the first support section (11) and filters a fluid; and a first extension section (31) that is disposed on the outside in the radial direction of the second support section (12) and that is joined to the first end member (4). The medium body 30 and the first extension portion 31 continuously extend in the axial direction with a third outer diameter D3. The first extension portion 31 is joined to the first end member 4 via a first joining portion 6. The first joining portion 6 includes a first protruding portion 6A having a fourth outer diameter D4 larger than the third outer diameter D3.

Description

Technical Field

[0001] This invention relates to metal fiber filters, filter units, and vaporizers. Background Technology

[0002] Patent Document 1 describes a filter assembly comprising a sintered fiber medium. This filter assembly has a cylindrical body with an outer diameter decreasing from a central portion toward one end of the assembly, and the fiber medium has a density increasing from the central portion toward one end of the assembly. Because the ends of this filter assembly are highly dense, it is expected that welding at those ends will be easier.

[0003] [Background Technical Documents]

[0004] [Patent Literature]

[0005] [Patent Document 1] Japanese Patent Publication No. 2011-502743 Summary of the Invention

[0006] [The problem the invention aims to solve]

[0007] like Figure 5 As shown, the filter assembly a described above may be housed within a housing b and used as a filter unit c. The housing b of the filter unit c has a fluid inlet d, an inlet flow path e that guides the fluid entering from the inlet d to the outer peripheral surface of the filter assembly a, and an outlet f for removing the fluid filtered by the filter assembly a.

[0008] In the filter unit c described above, the fluid flowing through the inlet flow path e tends to stagnate near the portion a1 with a reduced outer diameter located at the axial end of the filter assembly a. This fluid stagnation contributes to reduced filtration efficiency.

[0009] For example, such as Figure 6 As shown, even when the filter assembly a is disposed on a wall h in a large chamber, fluid tends to stagnate in the region a2 between the wall h and the portion with a reduced outer diameter at the axial end of the filter assembly a.

[0010] The present invention was conceived in view of the above-mentioned problems, and its main objective is to provide a metal fiber filter, etc., capable of suppressing fluid retention at the end of the filter medium (filter assembly).

[0011] [Problem-solving methods]

[0012] This invention provides a metal fiber filter, comprising:

[0013] The support body is formed into a cylindrical shape in a specified axial and radial direction, and has a first end;

[0014] The filter medium is disposed on the outer side of the support in the radial direction; and

[0015] The first end member is fixed to the side of the first end of the support body.

[0016] The aforementioned support body includes: a first support portion having a first outer diameter; and a second support portion located on the side of the first end of the first support portion, having a second outer diameter larger than the first outer diameter.

[0017] Multiple through holes are formed in the first support portion mentioned above.

[0018] The second support portion is connected to the first support portion and forms the first end.

[0019] The filter medium described above is a sintered body of metal fibers.

[0020] The filter medium comprises: a medium body disposed on the outer side of the first support portion in the radial direction and used for filtering fluid; and a first extension portion disposed on the outer side of the second support portion in the radial direction and joined to the first end member.

[0021] The aforementioned medium body and the aforementioned first extension extend continuously along the axial direction with a third outer diameter.

[0022] The first extension portion is joined to the first end member via the first joint portion.

[0023] The first joint includes a first raised portion, which has a fourth outer diameter that is larger than the third outer diameter.

[0024] In this invention, the first raised portion can be formed by welding beads.

[0025] In this invention, the wall thickness of the first extension can be in the range of 5% to 40% of the wall thickness of the medium body.

[0026] In this invention, the wall thickness of the above-mentioned medium body can be 4.0 mm or more.

[0027] In this invention, the first end member may have a fifth outer diameter greater than or equal to the third outer diameter.

[0028] In this invention, it is preferable that the second support portion is not provided with a through hole extending in the radial direction.

[0029] In this invention, the fourth outer diameter can be 1.0 mm or more larger than the third outer diameter.

[0030] In this invention, the porosity of the first extension may be less than the porosity of the medium body.

[0031] In this invention, the porosity of the first extension portion may be 70% or less, and the porosity of the medium body may be 80% or more.

[0032] In this invention, the first end member may be an end cap that blocks the first end of the support.

[0033] In this invention,

[0034] The aforementioned support body has a second end that is opposite to the first end.

[0035] The aforementioned support body includes a third support portion on the side of the second end of the aforementioned first support portion, the third support portion having a sixth outer diameter larger than the aforementioned first outer diameter.

[0036] The third support portion is connected to the first support portion and forms the second end.

[0037] A second end member is fixed to the side of the second end of the aforementioned support.

[0038] The filter medium includes a second extension, which is disposed on the outer side of the third support in the radial direction and engages with the second end member.

[0039] The aforementioned medium body and the aforementioned second extension extend continuously along the axial direction with respect to the aforementioned third outer diameter.

[0040] The second end of the second extension is joined to the second end member via the second joint.

[0041] The second joint includes a second raised portion, which has a seventh outer diameter that is larger than the third outer diameter.

[0042] In this invention, the second raised portion can be formed by welding beads.

[0043] In this invention, the wall thickness of the second extension can be in the range of 5% to 40% of the wall thickness of the medium body.

[0044] In this invention, the first end member can be an end cap that blocks the first end of the support body.

[0045] The aforementioned second end member is a housing assembly member, which is used to fix the second end of the aforementioned support body to the housing.

[0046] The second end member has an opening for removing fluid from the radially inner space of the support.

[0047] This invention can be a filter unit comprising: any of the aforementioned metal fiber filters; and

[0048] The aforementioned housing is capable of accommodating the aforementioned metal fiber filter.

[0049] The aforementioned housing has:

[0050] The inlet of the aforementioned fluid;

[0051] The inlet flow path guides the fluid entering from the inlet to the outer peripheral surface of the filter medium; and

[0052] The outlet is used to remove the fluid that has been filtered by the filter medium and flows through the through hole of the first support and the opening of the second end member.

[0053] The present invention can be a vaporizer using the metal fiber filter described in any of the above claims.

[0054] [The effects of the invention]

[0055] The metal fiber filter of the present invention can reduce the risk of fluid retention at the end of the filter medium and improve filtration efficiency. Attached Figure Description

[0056] [ Figure 1 [Illustration 1] is a cross-sectional view of the metal fiber filter in this embodiment.

[0057] [ Figure 2 ]yes Figure 1 Enlarged view of Part II.

[0058] [ Figure 3 ]yes Figure 1 Enlarged view of Part III.

[0059] [ Figure 4 [ ] is a cross-sectional view of a filter unit using the metal fiber filter of this embodiment.

[0060] [ Figure 5 [This is a cross-sectional view of a conventional filter unit.]

[0061] [ Figure 6 [This is a cross-sectional view of another conventional filter unit.] Detailed Implementation

[0062] Hereinafter, one embodiment of the present invention will be described with reference to the accompanying drawings.

[0063] To aid in understanding this invention, it should be understood that the accompanying drawings contain dimensions that differ from the actual construction. Furthermore, in cases where multiple embodiments exist, the same or common elements are labeled with the same symbols in the specification, and redundant descriptions are omitted. Moreover, the specific configurations shown in the embodiments and drawings are used to understand the content of this invention; however, this invention is not limited to the specific configurations illustrated.

[0064] [Metal Fiber Filter]

[0065] Figure 1 This is a cross-sectional view of the metal fiber filter 1 in this embodiment. Figure 1 As shown, the metal fiber filter 1 of this embodiment includes a support body 2, a filter medium 3 disposed on the outer side of the support body 2 in the radial direction, and a first end member 4 disposed on one end side of the support body 2 in the axial direction. Furthermore, the metal fiber filter 1 of this embodiment also includes a second end member 5 disposed on the other end side of the support body 2 in the axial direction.

[0066] The metal fiber filter 1 of this embodiment is used to capture foreign matter such as particles in a fluid. In particular, the metal fiber filter 1 of this embodiment can be used as a high-performance filter to capture foreign matter in the fluids used in the manufacturing process of industrial products (such as semiconductors) manufactured in an extremely clean environment with high filtration efficiency. However, the fluid that can be filtered by the metal fiber filter 1 of this invention is not limited to any particular type.

[0067] [Support body]

[0068] The support body 2 is configured as a cylinder with a defined axial direction and a radial direction orthogonal to it. In a cross-section orthogonal to the axial direction of the support body 2, the direction along its outer surface is defined as the circumferential direction. The support body 2 extends axially from a first end E1 to a second end E2. The interior of the support body 2 in the radial direction is defined as space i. In this embodiment, the support body 2 is configured as a cylinder with a circular cross-section. In other aspects, the support body 2 may also be configured as a cylinder with a polygonal cross-section.

[0069] The support 2 is made of a metallic material. There are no particular limitations on the metallic material; for example, stainless steel can be used, but Austenite-based stainless steel, which has excellent machinability and corrosion resistance, is particularly preferred. As a preferred embodiment, the support 2 in this embodiment is made of SUS316L, which has even better corrosion resistance.

[0070] Figure 2 Show Figure 1 An enlarged view of Part II. (See image below.) Figure 1 and Figure 2As shown, the support body 2 includes a first support portion 11 and a second support portion 12 disposed on the side of the first end E1 of the first support portion 11. In this embodiment, the first support portion 11 has a sufficiently large axial length compared to the second support portion 12.

[0071] [First Support Section]

[0072] The first support portion 11 is formed as a cylinder with a first outer diameter D1. In this embodiment, the first support portion 11 extends continuously along the axial direction with the first outer diameter D1.

[0073] A plurality of through holes 11a are formed in the first support portion 11. Therefore, fluid on the radially outer side of the first support portion 11 can flow into the internal space i of the first support portion 11 through the through holes 11a. In this embodiment, the first support portion 11 can be formed, for example, by machining a metal plate with holes formed at regular intervals, such as perforated metal, into a cylindrical shape. The diameter or shape of the through holes 11a is not particularly limited and can be appropriately set according to the application. In this embodiment, the through holes 11a are circular with a diameter of 1.5 mm, and they are arranged at approximately equal intervals along both the axial and circumferential directions.

[0074] [Second Support Section]

[0075] The second support portion 12 has a second outer diameter D2 that is larger than the first outer diameter D1. That is, the second support portion 12 protrudes outward in the radial direction from the outer surface of the first support portion 11. In this embodiment, the second support portion 12 is formed in an annular shape, for example including an outer peripheral surface 121 in the radial direction, an inner peripheral surface 122 in the radial direction, an inner end surface 123 in the axial direction, and an outer end surface 124 in the axial direction. Furthermore, in this specification, regarding the axial direction, "inner" and "outer" refer to opposite directions in the axial direction, with the direction toward the end in the axial direction defined as "outer" and the direction toward the center in the axial direction defined as "inner".

[0076] The outer peripheral surface 121 of the second support portion 12 extends continuously along the axial direction, for example, with a second outer diameter D2.

[0077] In this embodiment, for example, the end of the first support portion 11 is fixed to the inner peripheral surface 122 of the second support portion 12. More specifically, the inner peripheral surface 122 is formed as a stepped surface including a recess 122a extending axially with a certain inner diameter, and a protrusion 122b located on the side of the first end E1 of the recess 122a and protruding radially inward from the recess 122a. Furthermore, the end of the first support portion 11 is disposed in the recess 122a, and the outer end face of the first support portion 11 in the axial direction abuts against the stepped surface of the protrusion 122b. The first support portion 11 and the second support portion 12 are fixed together by welding or the like. In this embodiment, the inner peripheral surface of the first support portion 11 and the inner peripheral surface of the protrusion 122b of the second support portion 12 are formed continuously in the axial direction.

[0078] In this embodiment, the inner end face 123 of the second support portion 12 in the axial direction is, for example, a conical surface whose outer diameter gradually decreases towards the inner side in the axial direction.

[0079] In this embodiment, the outer end face 124 of the second support portion 12 in the axial direction is formed, for example, as a plane orthogonal to the axial direction, and this plane forms the first end E1 of the support body 2.

[0080] In this embodiment, the second support portion 12 is made of solid wood that extends radially without any through holes. Therefore, fluid cannot pass through the second support portion 12.

[0081] [Filter Media]

[0082] The filter medium 3 is fixed to the outer peripheral surface of the support 2 in the radial direction. Therefore, in this embodiment, the filter medium 3 is made into a cylindrical shape corresponding to the cylindrical shape of the support 2. Furthermore, in this embodiment, the filter medium 3 is fixed to the outer peripheral surface of the support 2 in the radial direction during sintering. However, there are no particular limitations on the method of fixing the filter medium 3 to the support 2.

[0083] The filter medium 3 is composed of a sintered body of metal fibers. There are no particular limitations on the metal fibers constituting the filter medium 3; for example, stainless steel, especially austenitic stainless steel with excellent corrosion resistance (such as SUS316L), nickel alloys, pure nickel, etc., can be appropriately used. There are also no particular limitations on the wire diameter of the metal fibers used in the filter medium 3; for example, short fibers of about 0.5 to 10 μm are ideal for improving filtration efficiency. After being placed on the outer peripheral surface of the support 2, these metal fibers are placed in a mold or similar container and subjected to external heat and pressure. Thus, the aggregate of metal fibers is integrally formed on the outer peripheral surface of the support 2 in the form of a cylindrical sintered body. This filter medium 3 has a porous structure with fine pores forming internally for fluid passage, and therefore functions as a filter component with high filtration accuracy.

[0084] The filter medium 3 includes a medium body 30 and a first extension 31 formed on the side of the first end E1 of the medium body 30. Furthermore, the filter medium 3 of this embodiment includes a second extension 32 formed on the side of the second end E2 of the medium body 30.

[0085] The media body 30 is the portion of the filter media 3 disposed radially outside the first support portion 11. The media body 30 performs the filtering function as is its original function as the filter media 3. In this embodiment, the media body 30 is a cylindrical shape extending axially, corresponding to the shape of the support 2. The first extension portion 31 is the portion of the filter media 3 disposed radially outside the second support portion 12. The first extension portion 31 is integrated with the media body 30. The first extension portion 31 is used for engagement with the first end member 4 described below.

[0086] exist Figure 2 In this embodiment, the medium body 30 and the first extension 31 extend continuously along the axial direction with a third outer diameter D3. That is, there is no substantial difference in size between the medium body 30 and the first extension 31, and they are continuous along the axial direction with the same outer diameter. However, since the filter medium 3 is a sintered body of metal fibers, slight unevenness exists on the surface of the filter medium 3 according to microscopic observation. Therefore, the term "no substantial difference in size" means that the unavoidable slight unevenness on the surface of such a sintered metal fiber body is permissible. More specifically, the term "no substantial difference in size" should be understood as being perceptible to those skilled in the art when observing the medium body 30 and the first extension 31 with the naked eye (macroscopic observation) under normal attention, as long as the continuity along the axial direction with the same outer diameter is identifiable. Furthermore, in the case of microscopic observation, by setting the difference between the maximum and minimum diameters of the filter medium 3 to, for example, 2 mm or less, preferably 1.5 mm or less, fluid retention can be suppressed more effectively.

[0087] [First end component]

[0088] The first end member 4 is fixed to the side of the first end E1 of the support 2. In this embodiment, the first end member 4 is configured, for example, as an end cap that plugs the side of the first end E1 of the cylindrical support 2. The first end member 4 has a plate shape formed of a metallic material, especially austenitic stainless steel with excellent corrosion resistance (SUS316L in this embodiment). The first end member 4 includes an end face that abuts against the inner side of the outer end face 124 in the axial direction of the second support portion 12. Through the first end member 4, fluid in the space i of the support 2 cannot flow out from the side of the first end E1 of the support 2.

[0089] Furthermore, the first extension 31 is joined to the first end member 4 via the first joint 6. In this embodiment, the first joint 6 also joins the first end member 4 to the second support portion 12 of the support body 2, but the first joint 6 only needs to join the first extension 31 to the first end member 4. Furthermore, the first joint 6 includes a first protrusion 6A having a fourth outer diameter D4 that is greater than the third outer diameter D3.

[0090] [The purpose of this implementation plan]

[0091] In the filter medium 3 of this embodiment, the medium body 30 and the first extension 31 extend continuously in the axial direction with a third outer diameter D3. That is, the radial outer surfaces of the medium body 30 and the first extension 31 are formed by continuous surfaces that do not have substantial recesses except for the microscopic unevenness of the medium. Furthermore, the first joint 6 includes a first bulge 6A having a fourth outer diameter D4 that is larger than the third outer diameter D3. Therefore, the metal fiber filter 1 of this embodiment can suppress the retention of the fluid to be filtered on the side of the first end E1. In addition, the first bulge 6A with a relatively large outer diameter (fourth outer diameter D4) can also guide the fluid to the side of the medium body 30 with a smaller outer diameter, for example. Based on the above, the metal fiber filter 1 of this embodiment helps to reduce the pressure loss of the fluid to be filtered and generate a uniform flow rate, and also has excellent filtration efficiency.

[0092] The preferred aspects of the present invention will be described below, but all of the following are arbitrary constituent elements of the present invention.

[0093] The first joint 6 can be formed by various joining methods. For example, the first joint 6 can be formed by fusion welding, welding, diffusion bonding, or friction pressing. From the viewpoint of preventing fluid leakage (short-circuiting) from the first joint 6, fusion welding, which easily produces an airtight joint, is particularly ideal, especially TIG welding. In this embodiment, the first joint 6 is formed by a continuous fusion weld bead along the circumferential direction, and the first raised portion 6A is also formed by the portion of the fusion weld bead that protrudes radially outward.

[0094] The radial protrusion of the first raised portion 6A relative to the outer surface of the filter medium 3 (i.e., (D4-D3) / 2) is not particularly limited, but from the viewpoint of expecting to improve the bonding strength or to guide the fluid to the side of the medium body 30, it can be preferably set to 0.5 mm or more, more preferably 0.9 mm or more. That is, the fourth outer diameter D4 is ideally 1.0 mm or more larger than the third outer diameter D3.

[0095] In this embodiment, the first extension 31 of the filter medium 3 has a wall thickness t1 smaller than that of the medium body 30. Furthermore, the first extension 31 is a porous structure made of sintered metal fibers, making it prone to deformation due to heat during welding. However, in this embodiment, the first extension 31 is supported radially from the inside by the second support 12, thus suppressing melting or pore formation during welding and achieving connection with the support body 2 and the first end member 4. Moreover, the filter medium 3 has an integral structure that connects with the support body 2 and the first end member 4, thus exhibiting high rigidity and excellent strength even under vibration or high pressure.

[0096] The outer diameter of the first end member 4 (hereinafter referred to as "the fifth outer diameter D5") is not particularly limited, but in this embodiment it is set to be greater than or equal to the third outer diameter D3 of the filter medium 3. Therefore, fluid retention can also be suppressed around the first end member 4.

[0097] There is no particular limitation on the wall thickness t0 of the medium body 30. In order to further improve the filtration accuracy, it can be set to 3.0 mm or more, preferably 3.5 mm or more.

[0098] The wall thickness t1 of the first extension 31 is not particularly limited; for example, it can be set to 5% or more, preferably 10% or more, and more preferably 15% or more of the wall thickness t0 of the medium body 30. By setting the wall thickness t1 of the first extension 31 to 5% or more of the wall thickness t0 of the medium body 30, for example, when the first extension 31 is welded to the first end member 4, melting of the first extension 31 can be more reliably suppressed, thereby forming an airtight first joint 6. This helps to effectively suppress short-circuiting of fluid near the first joint 6.

[0099] On the other hand, if the wall thickness t1 of the first extension 31 is too large, there is a concern that it will be difficult to form a deeper first joint 6 that reaches the second support 12. From this point of view, the wall thickness t1 of the first extension 31 can be set to, for example, 40% or less of the wall thickness t0 of the medium body 30, preferably 35% or less, and more preferably 30% or less.

[0100] Regarding the above viewpoint, as one aspect, when the wall thickness t0 of the medium body 30 is 5.0 mm, the wall thickness t1 of the first extension 31 is ideally set to the range of 0.25 to 2.0 mm, preferably the range of 0.50 to 1.75 mm, and more preferably the range of 0.75 to 1.5 mm.

[0101] Ideally, the porosity of the first extension portion 31 is lower than that of the dielectric body 30. This relatively increases the rigidity of the first extension portion 31, which engages with the first end member 4, and suppresses poor bonding during welding. In a preferred embodiment, the porosity of the first extension portion 31 may be set to, for example, 70% or less, preferably 65% ​​or less, and more preferably 60% or less. This porosity can be achieved, for example, by adjusting the compressibility acting on the first extension portion 31 to be higher than that of the dielectric body 30 during the sintering step. Furthermore, the first extension portion 31 is ideally a porous structure, for example, substantially comprising pores with a diameter of 2 to 6 μm.

[0102] In this specification, the "porosity" of a porous structure is expressed as the ratio of the volume of the pore portion to the apparent total volume of the target area. In this specification, the porosity is calculated. In this case, firstly, the mass of the filter medium is measured, and the volume, including the pores of the filter medium, is calculated. Secondly, the mass of solid wood, assumed to be the same as the volume of the filter medium, is measured. Then, the porosity can be calculated according to the following formula (1).

[0103] Porosity (%) = {1 - (mass of filter media / mass of solid wood)} * 100…(1)

[0104] Since the media body 30 is supported from the radial direction by the first support portion 11, a high differential pressure resistance relative to the fluid pressure during filtration can be ensured. Therefore, even if the fluid velocity is increased, deformation of the filter media 3 can be suppressed, which helps to improve the filtration efficiency. In order to fully exert the preferred filtration function, the porosity of the media body 30 can be set to be greater than that of the first extension portion 31. In a preferred aspect, the porosity of the media body 30 can be set to, for example, 80% or more, preferably 85% or more, and more preferably 90% or more. Similarly, the media body 30 can be configured as a porous structure that mainly includes pores larger than those of the first extension portion 31. In a preferred aspect, it is more ideal to configure the media body 30 as a porous structure that particularly mainly includes pores with a pore size of 5 to 30 μm.

[0105] [Third Support Section]

[0106] In this embodiment, the support body 2 further includes a third support portion 13 on the side of the second end E2 of the first support portion 11, having a sixth outer diameter D6 that is larger than the first outer diameter D1. That is, the third support portion 13 protrudes radially outward from the outer surface of the first support portion 11. The outer peripheral surface 131 of the third support portion 13 extends continuously in the axial direction, for example, with the sixth outer diameter D6. In this embodiment, the sixth outer diameter D6 is set to be the same as the second outer diameter D2 of the second support portion 12, but it may also be different.

[0107] The third support portion 13 has the same configuration as the second support portion 12, therefore its description is omitted. Specifically, the outer peripheral surface 131, inner peripheral surface 132, inner end surface 133, and outer end surface 134 of the third support portion 13 have the same configuration as the outer peripheral surface 121, inner peripheral surface 122, inner end surface 123, and outer end surface 124 of the second support portion 12. Furthermore, the end portion of the third support portion 13 on the side of the second end E2 of the first support portion 11 is fixed to the inner peripheral surface 132.

[0108] [Second end component]

[0109] A second end member 5 is fixed to the side of the second end E2 of the support body 2. In this embodiment, the second end member 5 is configured as a housing assembly member for fixing the side of the second end E2 of the support body 2 to the housing (described below). More specifically, the second end member 5 is disc-shaped with an opening 5a formed at its center. The second end member 5 is aligned with the axis of the support body 2 and fixed to the side of the second end E2 of the support body 2. The outer diameter of the second end member 5 has the largest eighth outer diameter D8 in the metal fiber filter 1, and its outer periphery is fixed to the housing described below. Furthermore, the opening 5a of the second end member 5 is used to extract fluid from the radially inner space i of the support body 2.

[0110] [Second Extension]

[0111] The filter medium 3 of this embodiment includes a second extension 32 disposed radially outside the third support portion 13 and engaging with the second end member 5. The second extension 32 is integrated with the medium body 30. The second extension 32 is used for engagement with the second end member 5 described below.

[0112] In this embodiment, the medium body 30 and the second extension 32 extend continuously along the axial direction with a third outer diameter D3. That is, there is no substantial step difference between the medium body 30 and the second extension 32; they are continuous along the axial direction with the same outer diameter. As mentioned above, the term "no substantial step difference" should be understood as meaning that, when a person skilled in the art observes the connection between the medium body 30 and the second extension 32 with the naked eye (macroscopic observation) under normal attention, the degree to which they are continuous along the axial direction with the same outer diameter is identifiable.

[0113] Furthermore, the second extension 32 is joined to the second end member 5 via the second joining portion 7. In this embodiment, the second joining portion 7 also joins the second end member 5 to the third support portion 13 of the support body 2, but the second joining portion 7 only needs to join the second extension 32 to the second end member 5. Furthermore, the second joining portion 7 includes a second protrusion 7A having a seventh outer diameter D7 that is larger than the third outer diameter D3.

[0114] In this embodiment, the media body 30 and the second extension 32 extend continuously along the axial direction with a third outer diameter D3. That is, the radially outer surfaces of the media body 30 and the second extension 32 are formed by continuous surfaces that do not have substantial recesses except for the microscopic unevenness of the media. Therefore, in this embodiment, the metal fiber filter 1 is substantially continuous along the axial direction with a third outer diameter D3 in the interval between the first joint 6 and the second joint 7 of the filter media 3. Therefore, the metal fiber filter 1 of this embodiment can also suppress the retention of fluid on the side of the second end E2 of the filter media 3. Furthermore, the second bulge 7A, with a relatively large outer diameter (seventh outer diameter D7), can also guide the fluid to the side of the media body 30 with a smaller outer diameter.

[0115] The second joint 7 can be formed by various joining methods. For example, the second joint 7 can be formed by fusion welding, welding, diffusion bonding, or friction pressing. From the viewpoint of preventing fluid leakage (short-circuiting) from the second joint 7, the joining method is particularly ideal as fusion welding, which easily produces an airtight joint, especially TIG welding. In this embodiment, the second joint 7 is also a continuous weld bead in the circumferential direction formed by fusion welding, and the second protrusion 7A is also formed by the portion of the weld bead that protrudes outward in the radial direction.

[0116] The radial protrusion of the second raised portion 7A relative to the outer surface of the filter medium 3 (i.e., (D7-D3) / 2) is not particularly limited, but from the viewpoint of expecting an improvement in the bonding strength or the effect of guiding the fluid to the medium body 30 side, it can be preferably set to 0.5 mm or more, more preferably 0.9 mm or more. That is, the seventh outer diameter D7 is ideally 1.0 mm or more larger than the third outer diameter D3.

[0117] In this embodiment, the second extension 32 of the filter medium 3 has a wall thickness t2 smaller than that of the medium body 30. Furthermore, the second extension 32 is a porous structure made of sintered metal fibers, making it prone to deformation due to heat during welding. However, in this embodiment, the second extension 32 is supported radially from the inside by the third support 13, thus suppressing melting or pore formation during welding and achieving connection with the support body 2 and the second end member 5, thereby suppressing fluid short-circuiting. Moreover, the filter medium 3 has an integral structure that connects with the support body 2 and the second end member 5, thus exhibiting high rigidity and excellent strength even under vibration or high pressure.

[0118] There is no particular limitation on the wall thickness t2 of the second extension 32. For example, it is ideal to set it to be within the same range as the wall thickness t1 of the first extension 31. That is, the wall thickness t2 of the second extension 32 can be set to 5% or more, preferably 10% or more, and more preferably 15% or more of the wall thickness t0 of the medium body 30.

[0119] On the other hand, if the wall thickness t2 of the second extension 32 is too large, there is a concern that it will be difficult to form a deeper second joint 7 that reaches the third support 13. From this point of view, the wall thickness t2 of the second extension 32 can also be set to, for example, 40% or less, preferably 35% or less, and more preferably 30% or less of the wall thickness t0 of the medium body 30.

[0120] From the above perspective, as one aspect, when the wall thickness t0 of the medium body 30 is 5.0 mm, the wall thickness t2 of the second extension 32 is also ideally set to, for example, a range of 0.25 to 2.0 mm, preferably a range of 0.50 to 1.75 mm, and more preferably a range of 0.75 to 1.5 mm.

[0121] Ideally, the porosity of the second extension 32 is less than that of the medium body 30. This relatively increases the rigidity of the second extension 32, which engages with the second end member 5, and suppresses poor bonding during welding. In a preferred embodiment, the porosity of the second extension 32 may be set to, for example, 70% or less, preferably 65% ​​or less, and more preferably 60% or less. Furthermore, the second extension 32 is ideally a porous structure, for example, substantially comprising pores with a diameter of 2 to 6 μm.

[0122] [case]

[0123] Figure 4 This is a cross-sectional view of the filter unit 100 of the metal fiber filter 1 using this embodiment. Figure 4As shown, the filter unit 100 includes a housing 101 having a space capable of accommodating the metal fiber filter 1. The housing 101 has a fluid inlet 102, an inlet flow path 103 that guides the fluid entering from the inlet 102 to the outer peripheral surface of the filter medium 3, and an outlet 104 for the fluid filtered by the filter medium 3.

[0124] The housing 101 is made of stainless steel, for example, preferably austenitic stainless steel. In this embodiment, the housing 101 is made of SUS316L, which has particularly excellent corrosion resistance. For example, when implemented as an in-line filter, the housing 101 forms the outer casing of the metal fiber filter 1.

[0125] exist Figure 4 In the filter unit 100, the fluid that is to be filtered enters from the inlet 102 and passes through the inlet flow path 103 between the housing 101 and the metal fiber filter 1, then flows back to the outer peripheral surface of the filter medium 3. As the fluid flows back to the outer peripheral surface of the filter medium 3, particles and other foreign matter are captured and purified by the filter medium 3. Furthermore, the purified fluid passes through the through hole 11a of the first support portion 11, through the space i inside the support body 2 and the opening 5a of the second end member 5, and is taken out from the outlet 104.

[0126] In the above-described filtration steps, as explained above, the outer surfaces of the filter medium 3's medium body 30, first extension 31, and second extension 32 are continuous along the axial direction with substantially the same third outer diameter D3. Furthermore, the first joint 6 and second joint 7 located at both ends of the filter medium 3 in the axial direction each have a first raised portion 6A and a second raised portion 7A with outer diameters greater than the third outer diameter D3, respectively. Therefore, fluid easily flows from the first raised portion 6A and the second raised portion 7A to the medium body 30 side, thereby suppressing stagnation on both sides of the medium body 30 in the axial direction. This reduces pressure loss during the filtration process and generates a uniform flow rate.

[0127] Furthermore, since the filter medium 3 is supported from the radial direction by the support body 2 from the inside, even though it is a porous structure, it can maintain a high differential pressure resistance during filtration. Therefore, the metal fiber filter 1 and filter unit 100 of this embodiment can be preferably used under high filtration pressure environments, which also helps to improve filtration efficiency.

[0128] The metal fiber filter 1 of this embodiment can reduce the pressure loss associated with filtration, thus preventing re-liquefaction within the filter medium 3, even when filtering low vapor pressure liquids. Therefore, the metal fiber filter 1 of this embodiment can also be flexibly used as a vaporizer. For example, in the semiconductor manufacturing process, when filtering a low vapor pressure liquid formed by vaporizing precursors, re-liquefaction within the filter medium 3 can be prevented.

[0129] The metal fiber filter 1 of the present invention may also be made without the housing 101. For example, as Figure 6 As shown, when the filtered gas is directly fed into the next step, or when it is implemented as a flow guide (exhaust filter) mounted in the vacuum chamber, the housing 101 is not required.

[0130] The embodiments of the present invention have been described in detail above, but the present invention is not limited to the specific disclosures above, and can be implemented by various modifications within the scope of the technical concept described in the patent application.

[0131] Figure Labels

[0132] 1: Metal fiber filter

[0133] 2: Support body

[0134] 3: Filter Media

[0135] 4: First end component

[0136] 5: Second end component

[0137] 5a: Opening

[0138] 6: First joint

[0139] 6A: First ridge

[0140] 7: Second joint

[0141] 7A: Second ridge

[0142] 11: First support section

[0143] 11a: Through hole

[0144] 12: Second support section

[0145] 13: Third support section

[0146] 30: Medium body

[0147] 31: First extension

[0148] 32: Second extension

[0149] 100: Filter Unit

[0150] 101: Shell

[0151] 102: Entrance

[0152] 103: Inlet Flow Path

[0153] 104: Exports

[0154] E1: First end

[0155] E2: Second end

Claims

1. A metal fiber filter comprising: a support body formed in a cylindrical shape defining an axial direction and a radial direction, and having a first end; a filter medium disposed outside the support body in the radial direction; and a first end member fixed to the first end side of the support body, the support body includes a first support portion having a first outer diameter, and a second support portion located on the first end side of the first support portion and having a second outer diameter larger than the first outer diameter, a plurality of through holes are formed in the first support portion, the second support portion is continuous with the first support portion and forms the first end, the filter medium is a sintered body of metal fibers, the filter medium includes a medium body disposed outside the first support portion in the radial direction and configured to filter a fluid, and a first extension portion disposed outside the second support portion in the radial direction and joined to the first end member, the medium body and the first extension portion continuously extend in the axial direction with a third outer diameter, the first extension portion is joined to the first end member via a first joining portion, the first joining portion includes a first protrusion portion having a fourth outer diameter larger than the third outer diameter.

2. The metal fiber filter of claim 1, wherein, the first protrusion portion is formed by a fusion bead.

3. The metal-fiber filter of claim 1, wherein, a wall thickness of the first extension portion is in a range of 5% to 40% of a wall thickness of the medium body.

4. The metal-fiber filter according to claim 3, wherein, a wall thickness of the medium body is 4.0 mm or more.

5. The metal-fiber filter of claim 1, wherein, the first end member has a fifth outer diameter of the third outer diameter or more.

6. The metal-fiber filter of claim 1, wherein, no through hole is formed in the second support portion in the radial direction.

7. The metal-fiber filter of claim 1, wherein, the fourth outer diameter is larger than the third outer diameter by 1.0 mm or more.

8. The metal-fiber filter of claim 1, wherein, a porosity of the first extension portion is smaller than a porosity of the medium body.

9. The metal-fiber filter of claim 1, wherein, the porosity of the first extension portion is 70% or less, and the porosity of the medium body is 80% or more.

10. The metal-fiber filter of claim 1, wherein, the first end member is an end cap that plugs the first end side of the support body.

11. The metal-fiber filter of claim 1, wherein, the support body has a second end opposite to the first end, the support body includes a third support portion on the second end side of the first support portion, the third support portion having a sixth outer diameter larger than the first outer diameter, the third support portion is continuous with the first support portion and forms the second end, a second end member is fixed to the second end side of the support body, the filter medium includes a second extension portion disposed outside the third support portion in the radial direction and joined to the second end member, the medium body and the second extension portion continuously extend in the axial direction with the third outer diameter, the second end side of the second extension portion is joined to the second end member via a second joining portion, the second joining portion includes a second protrusion portion having a seventh outer diameter larger than the third outer diameter.

12. The metal-fiber filter of claim 11, wherein, the second protrusion portion is formed by a fusion bead.

13. The metal-fiber filter of claim 11, wherein, a wall thickness of the second extension portion is in a range of 5% to 40% of a wall thickness of the medium body.

14. The metal-fiber filter of claim 11, wherein, the first end member is an end cap that plugs the first end side of the support body, The second end member is a housing fitting member for fixing the side of the second end of the support body to a housing, The second end member has an opening portion for extracting fluid from the space inside the support body in the radial direction.

15. A filter unit comprising: the metal fiber filter according to claim 14; and The housing is capable of accommodating the metal fiber filter, The housing has: An inlet for the fluid; An inlet flow path for guiding the fluid that has entered from the inlet toward the outer peripheral surface of the filter medium; and An outlet for extracting the fluid that has been filtered by the filter medium and that has flowed through the through hole of the first support portion and the opening portion of the second end member.

16. A gasifier using the metal fiber filter according to any one of claims 1 to 14.

Images