Magnetic foreign matter removal device

Abstract

To provide a magnetic foreign matter removal device that is able to reduce the attraction leakage of magnetic foreign matter.SOLUTION: A magnetic foreign matter removal device 10 has: a casing 20 having an inlet 25 and an outlet 27; and a magnetic member 30. The magnetic member 30 has: a magnet case 50; and a plurality of magnets 60 housed in the magnet case 50, with the same poles facing each other via a yoke 65. The magnet case 50 has a wall portion 51 extending continuously in a circumferential direction of the casing 20. The plurality of wall portions 51 is arranged at predetermined intervals S toward an inner circumferential surface 20a of the casing 20 from an axis C extending from the inlet 25 of the casing 20 toward the outlet and passing through the center of the outlet.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a magnetic foreign matter removal device for removing magnetic foreign matter from powder or granular material or fluid containing magnetic foreign matter by adsorption using a magnetic field. [Background technology]

[0002] For example, foreign matter must be strictly removed from powders and granules, such as flour, that are used as food ingredients, and from fluids. Known devices for removing magnetic foreign matter from such powders and granules include a casing into which the powder and granules are introduced and a magnet disposed inside the casing. When the powder and granules are introduced through an upper opening of the casing, the magnetic foreign matter is attracted by the magnet, thereby removing the magnetic foreign matter from the powder and granules.

[0003] For example, Patent Document 1 listed below describes a magnetic powder remover having a hopper with an inlet through which food is put, multiple tubes arranged below the inlet, and multiple magnet bars inserted and removed from each tube. The multiple tubes are arranged at predetermined intervals within the hopper.

[0004] As the food passes between the multiple tubes arranged inside the hopper, magnetic foreign matter in the food is attracted and removed by the magnetic field from the magnet bar. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-172232 Summary of the Invention [Problem to be solved by the invention]

[0006] In the magnetic powder removal device of Patent Document 1, multiple tubes with magnetic bars inserted are arranged inside a hopper, but because the gaps between the tubes are relatively large, magnetic foreign matter may not be adsorbed completely from food passing through the gaps, and some may be missed.

[0007] In particular, it is often difficult to place the magnet bar close to the inner sidewall of the hopper, which tends to turn the inner sidewall of the hopper into a dead space where the magnetic field of the magnet bar cannot reach, making it easy for magnetic foreign matter to leak.

[0008] In addition, the magnetic field at both ends of the magnet bar in the axial direction is weaker than that at the center in the axial direction, so there is a lot of attraction leakage at both ends of the magnet bar. If multiple magnet bars like this are installed, there will be more locations in the hopper where attraction leakage occurs.

[0009] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a magnetic foreign matter removal device that can reduce the amount of magnetic foreign matter that is adsorbed and leaks from powder or fluid containing magnetic foreign matter. [Means for solving the problem]

[0010] In order to achieve the above-mentioned object, the present invention provides a magnetic foreign matter removal device that uses a magnetic field to adsorb and remove magnetic foreign matter from powder or granular material or fluid containing the magnetic foreign matter, and includes a casing having an inlet for introducing the powder or granular material and an outlet for discharging the powder or granular material or fluid, and a magnetic member arranged inside the casing to adsorb and remove the magnetic foreign matter, the magnetic member including a magnet case and a plurality of magnets stored in the magnet case with like poles facing each other via a yoke, the magnet case having a wall portion that extends continuously circumferentially of the casing, and multiple wall portions that are arranged at predetermined intervals from an axis that extends from the inlet of the casing toward the outlet and passes through the center of the outlet, toward the inner surface of the casing.

[0011] According to the above invention, the wall portions of the magnet case of the magnetic member are configured to be arranged at multiple intervals from the axis of the casing toward the inner surface of the casing, so that the wall portions of the magnet case of the magnetic member can be arranged densely over a wide area within the casing to the extent that powder or fluid can pass through, and it becomes easier to arrange the wall portions of the magnet case close to the inner surface of the casing, making it less likely that dead space will occur on the inner surface of the casing.

[0012] Furthermore, because the magnet case has a wall portion that extends continuously in the circumferential direction of the casing, the magnetic member can be structured so that there are no ends where the magnetic field is weak (for example, a structure in which the magnet case of the magnetic member is annular), or even if there are ends of the magnetic member, these ends can be positioned as close as possible to the inner peripheral surface of the casing. In the former case, it is possible to reduce the number of locations where attraction leakage occurs, and in the latter case, it is possible to make attraction leakage less likely to occur at the ends of the magnetic member compared to, for example, a linear structure of the magnetic member.

[0013] Therefore, this magnetic foreign matter remover can reduce the amount of magnetic foreign matter that is attracted and leaks from powder or fluid.

[0014] In the magnetic foreign matter removal device of the present invention, it is preferable that the wall portion of the magnet case forms a ring shape without any gaps in the circumferential direction, and that the magnetic member has multiple members of similar shapes but different outer dimensions, and is arranged in a multiple ring shape inside the casing.

[0015] According to the above aspect, since the wall portion of the magnet case of the magnetic member has the above structure, the magnetic member is easier to manufacture and the cost of the entire device can be reduced. Furthermore, by appropriately adjusting the shape and number of the magnetic members, it is possible to flexibly respond to changes in the size and shape of the internal space of the casing, thereby increasing versatility.

[0016] Furthermore, the magnetic member has a ring-shaped wall portion of the magnet case that is continuous in the circumferential direction, so it does not have both ends in the axial direction where the magnetic field is weak, as is the case with the linear magnet bar described in Patent Document 1. In other words, it is possible to create a structure without any areas where the magnetic field is weak, which can further reduce the attraction and leakage of magnetic foreign matter from powder and granular materials, etc.

[0017] In the magnetic foreign matter removal device of the present invention, the casing is formed so that the inner peripheral dimension on the discharge outlet side is smaller than the inner peripheral dimension on the inlet side, and the wall portion of the magnet case has a spiral shape that is continuously wound in a spiral shape along the axis, and is preferably arranged so as to follow the inner peripheral surface of the casing and be spaced apart from the inner peripheral surface of the casing.

[0018] According to the above aspect, since the wall portion of the magnet case has a continuously wound spiral shape, it is possible to improve the workability when placing the magnetic member inside the casing and also improve the workability when removing the magnetic member from inside the casing. Furthermore, when the casing has a structure that expands at the top and narrows toward the bottom (hopper structure), it is possible to make it more difficult for dead space to occur on the inner peripheral surface of the casing.

[0019] In the magnetic foreign matter removal device of the present invention, it is preferable that the wall portion of the magnet case has a spiral shape that is continuously wound in a spiral shape from the axis of the casing toward the inner surface of the casing.

[0020] According to the above aspect, since the wall portion of the magnet case has a continuously wound spiral shape, it is possible to improve the workability when placing the magnetic member inside the casing and also improve the workability when removing the magnetic member from the inside of the casing. In addition, it is easy to handle when the casing has a structure such as a transfer pipe.

[0021] In the magnetic foreign matter removal device of the present invention, it is preferable that the magnet case has a shape with corners, and the yoke located between the magnet located at the corner of the magnet case and another magnet adjacent to that magnet has an expandable spring shape.

[0022] According to the above aspect, the magnet located at the corner of the magnet case and the yoke located between the other magnets are in the form of an expandable spring, so that the yoke can be placed at the corner of the magnet case with less risk of movement, and the adhesive force from the yoke can be exerted stably.

[0023] In the magnetic foreign matter remover of the present invention, it is preferable that the magnetic member is held in a state spaced apart from the inner peripheral surface of the casing via a holding member.

[0024] According to the above aspect, the magnetic member is held at a distance from the inner surface of the casing via the retaining member, thereby preventing the accumulation of powder and granular materials between the inner surface of the casing and the outer periphery of the magnetic member, and allowing the powder and granular materials to pass smoothly through the gap between the inner surface of the casing and the outer periphery of the magnetic member, thereby further reducing the absorption and leakage of magnetic foreign matter from the powder and granular materials. [Effects of the Invention]

[0025] According to the present invention, the walls of the magnet cases of the magnetic members can be arranged densely over a wide area within the casing to the extent that powder or fluid can pass through, and the walls of the magnet cases can be easily arranged close to the inner surface of the casing, making it less likely that dead space will be created on the inner surface of the casing, thereby reducing the amount of magnetic foreign matter adsorbed and leaking from the powder or fluid. [Brief explanation of the drawings]

[0026] [Figure 1] 1 is a schematic diagram showing a first embodiment of a magnetic foreign matter remover according to the present invention. [Figure 2] FIG. 2 is a plan view illustrating the magnetic foreign matter removal device. [Figure 3] FIG. 2 is a perspective view showing one embodiment of a magnetic member used in the magnetic foreign matter removal device. [Figure 4] FIG. 4 is a cross-sectional view taken along the line AA in FIG. 3. [Figure 5] FIG. 5 is a cross-sectional view taken along the line BB in FIG. 4. [Figure 6] FIG. 2 is a schematic diagram showing a first modified example of the first embodiment of the magnetic foreign matter remover according to the present invention. [Figure 7] FIG. 10 is an explanatory plan view showing a second modified example of the first embodiment of the magnetic foreign matter remover according to the present invention. [Figure 8] FIG. 8 is a cross-sectional view of the magnetic member in FIG. [Figure 9] FIG. 10 is an explanatory plan view showing a third modified example of the magnetic foreign matter remover according to the first embodiment of the present invention. [Figure 10] FIG. 10 is an explanatory view showing a state in which a plurality of magnetic members are arranged in a casing in the second modified example. [Figure 11] 11 is an explanatory diagram showing a state in which a plurality of magnetic members are arranged in a casing in a layout different from that of FIG. 10 in the second modified example. FIG. [Figure 12] FIG. 2 is a schematic diagram showing a second embodiment of a magnetic foreign matter remover according to the present invention. [Figure 13] 2 is a partially cross-sectional plan view showing one embodiment of a magnetic member used in the magnetic foreign matter removal device. FIG. [Figure 14] FIG. 2 is a perspective view showing one embodiment of a magnetic member used in the magnetic foreign matter removal device. [Figure 15] FIG. 10 is an explanatory plan view showing a modified example of the second embodiment of the magnetic foreign matter remover according to the present invention. [Figure 16] FIG. 10 is a schematic diagram showing a third embodiment of a magnetic foreign matter remover according to the present invention. [Figure 17] FIG. 2 is a perspective view showing one embodiment of a magnetic member used in the magnetic foreign matter removal device. [Figure 18]FIG. 10 is an explanatory plan view showing a first modified example of the third embodiment of the magnetic foreign matter remover according to the present invention. [Figure 19] FIG. 19 is a cross-sectional view illustrating the magnetic member in FIG. 18. [Figure 20] FIG. 10 is an explanatory plan view showing a second modified example of the third embodiment of the magnetic foreign matter remover according to the present invention. [Figure 21] FIG. 21 is a cross-sectional view illustrating the magnetic member in FIG. 20. [Figure 22] FIG. 10 is an explanatory plan view showing a third modified example of the third embodiment of the magnetic foreign matter remover according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0027] (One embodiment of a magnetic foreign matter removal device) A first embodiment of a magnetic foreign matter remover according to the present invention (a structure in which magnetic members are arranged in multiple rings) will be described below with reference to FIGS.

[0028] As shown in Figure 1, the magnetic foreign matter removal device 10 in this embodiment (hereinafter also referred to simply as "removal device 10") uses a magnetic field to adsorb and remove magnetic foreign matter from powder or granular material or fluid containing magnetic foreign matter, and has a casing 20 having an inlet 25 for introducing powder or granular material or fluid and an outlet (not shown) for discharging the powder or granular material or fluid, and a plurality of magnetic members 30, 31, 32, 33, 34 arranged inside the casing 20 to adsorb and remove magnetic foreign matter.

[0029] In addition, the removal device 10 further has a holding member 70 inside the casing 20 for holding the multiple magnetic members 30, 31, 32, 33, 34 at a distance from the casing 20 while maintaining their shape, structure, relative positioning, layout, correlation, etc.

[0030] The casing 20 is formed so that the inner circumferential dimension on the discharge port side (not shown) is smaller than the inner circumferential dimension on the inlet 25 side.

[0031] More specifically, the casing 20 in this embodiment has a main body 21 having a generally cylindrical shape extending in the vertical direction with a constant diameter, an inclined portion 23 having a generally conical cylindrical shape (generally funnel-shaped) extending downward from the lower end of the extending direction of the main body 21 so as to gradually reduce in diameter, and an extending portion 24 extending with a constant diameter from the tip of the extending direction of the inclined portion 23. An inlet 25 is provided at the upper opening of the main body 21, and an outlet (not shown) is provided below the extending portion 24.

[0032] That is, the casing 20 of this embodiment is a so-called hopper, with an inlet located at the top and an outlet located at the bottom, so that powder or granular material or fluid falls naturally by gravity.

[0033] Furthermore, the inlet 25 and the outlet (not shown) are both substantially circular holes, and the inlet 25 and the outlet are arranged concentrically. The line extending from the inlet 25 of the casing 20 to the outlet and passing through the center of the outlet is defined as an axis C.

[0034] The holding member 70 has an annular base frame 71 and a plurality of diagonal frames 72 that extend diagonally downward from the inner peripheral edge of the base frame 71 at equal intervals in the circumferential direction toward the discharge port side of the casing 20. The holding member 70 as a whole has a structure in which the diameter increases upward and gradually decreases downward. In this example, four diagonal frames 72 are provided.

[0035] Furthermore, the base frame 71 has the largest outer diameter among the multiple magnetic members 30, 31, 32, 33, and 34, and has an outer diameter larger than the outer diameter of the magnetic member 34 located at the top of the casing 20, and this base frame 71 is located on the ceiling surface side of the magnetic member 34 and serves as the part that fixes the magnetic member 34.

[0036] Furthermore, the outer periphery of the base frame 71 is supported by the boundary between the lower end of the main body 21 of the casing 20 and the upper end of the inclined portion 23 (see FIG. 1). As a result, the holding member 70 is disposed inside the casing 20 via the base frame 71.

[0037] On the other hand, each of the diagonal frames 72 is connected to the inner periphery of the magnetic members 34, 33, 32, 31, and 30 by welding or the like, so that the positions and layout of the magnetic members 34, 33, 32, 31, and 30 are maintained.

[0038] Furthermore, the plurality of magnetic members 30, 31, 32, 33, and 34 are connected to one another via a holding member 70 to form a single assembly (magnetic member assembly) as a whole.

[0039] The holding member 70 having the above-described configuration holds the multiple magnetic members 34, 33, 32, 31, 30 in a spaced-apart state relative to the inner surface 20a of the casing 20 (the inner surfaces of the main body portion 21, the inclined portion 23, and the extension portion 24) while maintaining a layout that forms multiple rings in the axial direction of the casing 20.

[0040] It can also be said that the plurality of magnetic members 34, 33, 32, 31, and 30 are held in a suspended state inside the casing 20 by the holding member 70.

[0041] Each of the magnetic members 30, 31, 32, 33, and 34 has a magnet case 50 and a plurality of magnets 60 housed in the magnet case 50 with the same poles facing each other via a yoke 65.

[0042] Furthermore, each magnetic member 30, 31, 32, 33, 34 has a wall portion 51 of the magnet case 50 that forms a continuous ring in the circumferential direction, and has multiple members of similar shapes but different outer dimensions, and is arranged inside the casing 20 in a multiple ring shape.

[0043] 3 shows one specific magnetic member, and as shown in the figure, the magnet case 50 of each of the magnetic members 30, 31, 32, 33, and 34 is configured so that its wall portion 51 is annular (circular ring-shaped) as a whole. In addition, in the present invention, "annular" means a shape without discontinuities in the circumferential direction, that is, a shape that extends continuously in the circumferential direction without any divided or cut portions in the circumferential direction.

[0044] The annular magnet case 50 is formed, for example, by joining one end and the other end in the extension direction of a single cylindrically extending wall constituent to each other, or by preparing a plurality of wall constituents each having a substantially arc shape, arranging the wall constituents in an annular shape, and joining adjacent ends in the circumferential direction to each other.

[0045] Note that Figure 4 shows a cross section taken along the line AA in Figure 3 (a cross section perpendicular to the opening direction of the annular portion of the magnetic member), and Figure 5 shows a cross section taken along the line BB in Figure 1 (a cross section perpendicular to the extension direction of the annular portion of the magnetic member 30).

[0046] 5, the wall 51 of the magnet case 50 has a cylindrical cross section with a constant thickness. That is, the wall 51 of the magnet case 50 has a circular shape over the entire inner periphery (entire inner circumference) and the entire outer periphery (entire outer circumference).

[0047] 2, the outer diameter of the magnet case 50 increases (expands) in the order of the magnetic members 30, 31, 32, 33, and 34. Note that the outer dimension of the magnetic member means the outer diameter when the magnetic member is annular as in this embodiment, and means the largest outer dimension (maximum outer dimension) when the magnetic member is rectangular or annular.

[0048] As shown in range A in Figure 2, from the axis C of the casing 20 toward the inner surface 20a of the casing 20, the wall 51 of the magnet case 50 of magnetic member 30, the wall 51 of the magnet case 50 of magnetic member 31, the wall 51 of the magnet case 50 of magnetic member 32, the wall 51 of the magnet case 50 of magnetic member 33, and the wall 51 of the magnet case 50 of magnetic member 34 are arranged in this order with a predetermined interval S between them.

[0049] That is, the magnet case 50 is configured so that a plurality of wall portions 51 extending continuously in the circumferential direction of the casing 20 are arranged at predetermined intervals S from the axis C of the casing 20 toward the inner circumferential surface 20a.

[0050] Furthermore, magnetic members 30, 31, 32, 33, and 34 are arranged concentrically at different heights from the bottom to the top of casing 20, that is, so that the radial centers of magnetic members 30, 31, 32, 33, and 34 coincide with axis C of casing 20.

[0051] 1, magnetic member 30 is disposed near the leading end of inclined portion 23 of casing 20 in the extending direction. Magnetic members 31, 32, 33, and 34 are disposed along inner circumferential surface 20a of casing 20. As a result, magnetic members 30, 31, 32, 33, and 34 are disposed inside casing 20 in order from bottom to top.

[0052] The outer peripheries of the wall portions 51 of the magnet case 50 of the magnetic members 30, 31, 32, 33, and 34 do not contact the inner periphery 20a of the casing 20 but are spaced apart from it.

[0053] As described above, multiple magnetic members 30, 31, 32, 33, and 34 are arranged inside the casing 20 via the retaining member 70, and as a result, when the removal device 10 is viewed from the direction of the axis C of the casing 20 (when viewed from a planar direction), as shown in Figure 2, the magnetic members 30, 31, 32, 33, and 34 are arranged to form multiple circular rings.

[0054] In this embodiment, as shown in FIG. 2, when the casing 20 is viewed in the axial direction, a plurality of magnetic members are arranged so that a gap (predetermined interval S) is formed between adjacent magnetic members.

[0055] However, it is preferable that the multiple magnetic members be arranged so that there are no gaps between adjacent magnetic members when the casing is viewed in the axial direction, in order to prevent powder and granular materials from passing through without coming into contact with the magnetic members.

[0056] The magnet cases 50 of the magnetic members 30, 31, 32, 33, and 34 are made of stainless steel (austenitic stainless steel) such as SUS304 or SUS316, or non-magnetic materials such as aluminum alloy, titanium alloy, synthetic resin, and silicone.

[0057] In addition, the magnetic member is made up of multiple magnets 60, and these multiple magnets 60 are stored in the magnet case 50 with the same poles facing each other via a yoke 65, and the multiple magnets 60 are arranged in a ring shape.

[0058] More specifically, in this embodiment, each magnet 60 is a permanent magnet in the shape of a cylinder (solid round bar) with a constant outer diameter and a predetermined length. One end of the magnet 60 in the extension direction forms a north pole 61, and the other end in the extension direction forms a south pole 62. In addition, in this embodiment, the yoke 65 is a plate-like body made of metal such as pure iron or low-carbon steel. The yoke may be made of a metal material having rubber properties, so-called metal putty, magnetic silicone, or the like.

[0059] Alternatively, connecting holes may be formed in the connecting direction of the plurality of magnets, and a linear body may be inserted through these connecting holes to connect the plurality of magnets in a string-like fashion via the yokes.Alternatively, connecting holes may be formed in the connecting direction of the plurality of yokes, and a linear body may be inserted through these connecting holes to connect the plurality of yokes in a string-like fashion via the magnets.

[0060] With the above-described configuration, the adhesion between the magnet and the yoke inside the case can be increased, and the occurrence of gaps between adjacent magnets and yokes can be suppressed.

[0061] 4, the plurality of magnets 60 are housed and arranged in the magnet case 50 with the north poles 61, 61 of adjacent magnets 60, 60 facing each other and a yoke 65 interposed between the north poles 61, 61, or with the south poles 62, 62 of adjacent magnets 60, 60 facing each other and a yoke 65 interposed between the south poles 62, 62. As a result, the plurality of magnets 60 are arranged in the magnet case 50 so as to form a ring.

[0062] Furthermore, by disposing the yoke 65 between adjacent magnets 60, 60 with the same poles, the magnetic force of the magnets 60 acts on the yoke 65, and the yoke 65 becomes a portion that attracts magnetic foreign matter.

[0063] (Modification of magnetic foreign matter removal device) The structure and shape of the magnetic foreign matter remover of the present invention, and the shapes and structures of the casing and magnetic members that make up the magnetic foreign matter remover, are not limited to the above embodiments.

[0064] The main body constituting the casing may be, for example, a substantially rectangular or elliptical cylindrical shape, and the inclined portion constituting the casing may be, for example, a substantially pyramidal cylindrical shape that widens at the top and narrows at the bottom, or may be a cylindrical shape in which the outlet extends eccentrically relative to the inlet.

[0065] Also, in this embodiment, five magnetic members are arranged inside the casing 20, but the number of magnetic members arranged inside the casing may be one, two, three, four, six or more, and is not particularly limited.

[0066] Furthermore, although the casing 20 in this embodiment is a so-called hopper as described above, the casing may also be a transfer pipe (which can also be called a conveying pipe, a transfer case, or a transport case) that transfers powder or granular material or fluid by air, gas, vibration, a conveyor, etc. In this case, the inlet and outlet are oriented along the horizontal direction or tilted at a predetermined angle relative to the horizontal direction, and in this case, it is preferable that the opening direction of the magnetic member is oriented in the conveying direction of the powder or granular material or fluid.

[0067] On the other hand, the magnetic member does not have to be circular, but may be, for example, a polygonal ring such as a triangle, a square, a pentagon, or a hexagon, an elliptical ring, a rectangular ring with arc-shaped longitudinal ends, or an irregular ring formed by a combination of a curved shape and an angular shape, and is not particularly limited thereto.

[0068] FIG. 6 shows a first modified example of the first embodiment.

[0069] 6, in this first modified example, the shape of a holding member 70A is different from the structure in FIG. 1. That is, the holding member 70A has a protruding portion 71a on the outer periphery of the base frame 71, which protrudes more than the outer periphery of the magnetic member 34. The protruding portion 71a is placed on the upper end portion 21a of the main body 21 of the casing 20.

[0070] As a result, the plurality of magnetic members 34, 33, 32, 31, and 30 are held by the holding member 70A in a state spaced apart from the inner circumferential surface 20a of the casing 20 while maintaining the multiple annular layout.

[0071] In this first modified example, the plurality of magnetic members 34, 33, 32, 31, and 30 can be spaced apart from the inner circumferential surface 20a of the casing 20 with larger gaps than in the structure of FIG.

[0072] In the holding member 70 shown in Figures 1 and 6, the annular magnetic members 30, 31, 32, 33, and 34 are connected to the outer periphery of multiple diagonal frames 72, but the holding structure of multiple magnetic members by the holding member 70 is not limited to this.

[0073] For example, an engagement means may be provided on one of the diagonal frame or the magnetic member that constitutes the holding member to detachably engage both the diagonal frame and the magnetic member, and the magnetic member may be engaged and held in place by engaging with the diagonal frame via the engagement means.

[0074] As an example, a structure can be adopted in which multiple curved recesses are formed at the same height on the inner periphery of multiple diagonal frames 72, and magnetic members are held in place by being fitted into and engaged with these recesses.

[0075] More specifically, a first recess, a second recess, a third recess, a fourth recess, and a fifth recess are formed on the inner periphery of each oblique frame 72 in order from the bottom of the oblique frame, and by fitting and engaging the corresponding magnetic members into each recess, it becomes possible to hold the multiple magnetic members 30, 31, 32, 33, and 34 while maintaining a multiple annular layout in the axial direction of the casing. In this structure, each recess serves as the above-mentioned "engagement means."

[0076] 7 and 8 show a second modified example of the first embodiment.

[0077] 7, this first modified example has a structure in which a plurality of angular annular magnetic members 30A, 31A, 32A, 33A, and 34A are arranged in a casing 20 so as to form multiple annular shapes when viewed from above the removal device 10. In this case, it is preferable that the inclined portion 23 of the casing 20 has a substantially pyramidal cylindrical shape.

[0078] Furthermore, the magnet case 50 of the magnetic members 30A, 31A, 32A, 33A, and 34A is configured to have a rectangular annular shape (rectangular ring shape) having corners 54. Specifically, the magnet case 50 has a rectangular annular shape having four corners 54, and each corner 54 has a slightly rounded shape.

[0079] The magnetic member is made up of a plurality of magnets 60, which are stored in a linear portion of the magnet case 50 with the same poles facing each other via a yoke 65, and are arranged in a ring shape.

[0080] Furthermore, as shown in Figure 8, the yoke 65A located between the magnet 60 located at the corner 54 of the magnet case 50 and another magnet 60 adjacent to that magnet 60 (the magnet located at the end of the linear portion) is in the form of an expandable spring. Specifically, the yoke 65A is in the form of a spring made by bending a predetermined metal plate material into multiple accordion-like shapes. Note that the yoke may also be in the form of a coil spring made by winding a predetermined metal wire material.

[0081] Furthermore, when connecting the magnets located at the corners and the magnets located at the ends of the linear portions, instead of using the spring-shaped yoke 65A, the magnets may be connected in a string-like fashion using a linear body.

[0082] Furthermore, in the embodiments shown in Figures 1 and 6, the annular magnetic members 30, 31, 32, 33, and 34 are arranged concentrically at different heights, but multiple magnetic members of similar shapes may also be arranged concentrically at the same height.

[0083] For example, in the third modified example of the first embodiment shown in Figures 9 and 10, a plurality of magnetic members 30, 31, 32, 33, and 34 each having an annular shape are arranged concentrically at the same height (the plurality of magnetic members 30, 31, 32, 33, and 34 are arranged to form multiple concentric annular shapes at the same height).

[0084] The holding member 70B has a base frame 71 in the shape of an annulus that is larger than the outer diameter of the maximum outer diameter of the magnetic member 34, and a support frame 73 that is arranged in a generally cross shape on the inner periphery of the base frame 71. The magnetic members 31, 31, 32, 33, and 34 are supported and fixed to the base frame 71 and the support frame 73 at predetermined locations on one end of the magnetic members 31, 31, 32, 33, and 34 that faces the opening.

[0085] As a result, the plurality of magnetic members 30, 31, 32, 33, and 34 are connected to one another via the holding member 70B, and form a single assembly (magnetic member assembly) as a whole.

[0086] The support frame may be, for example, lattice-shaped, and may be any frame capable of supporting a plurality of magnetic members.

[0087] As shown in Figure 10, a support member 75 made of a wire mesh or the like that allows powder and fluid to pass through is supported at the boundary between the lower end of the main body 21 of the casing 20 and the upper end of the inclined portion 23, and further, a plurality of magnetic members 30, 31, 32, 33, 34 are placed on this support member 75 via a holding member 70B.

[0088] As a result, the holding member 70B holds the multiple magnetic members 34, 33, 32, 31, and 30 in a spaced-apart state relative to the inner circumferential surface 20a of the casing 20 while maintaining a layout in which the magnetic members 34, 33, 32, 31, and 30 form multiple concentric rings at the same height.

[0089] Furthermore, the plurality of magnetic members 34, 33, 32, 31, and 30 held by the holding member 70B as described above may be arranged in the casing 20 by placing the outer peripheral portion of the support member 75 on the upper end portion 21a of the main body portion 21 of the casing 20, as shown in FIG. 11.

[0090] In this case as well, the holding member 70B can hold the plurality of magnetic members 34, 33, 32, 31, and 30 in a state spaced apart from the inner circumferential surface 20a of the casing 20 while maintaining the multiple annular layout.

[0091] Furthermore, although the magnet 60 in this embodiment is cylindrical, the magnet may be, for example, a rod-shaped one with a square cross section, a rod-shaped one with an oval cross section, or a rod-shaped one with a semi-cylindrical cross section, or may have a cylindrical (donut-shaped, ring-shaped) or square tube-shaped cross section even if the cross section is not solid.

[0092] (Effects of magnetic foreign matter removal device) Next, the method of use and the effects of the removal device 10 having the above structure will be described.

[0093] That is, powder or granular material or fluid containing magnetic foreign matter (hereinafter simply referred to as "powder or granular material, etc.") is introduced into the main body 21 of the casing 20 through the inlet 25 of the casing 20 of the removal device 10. Then, the powder or granular material, etc. introduced into the main body 21 falls naturally due to gravity and enters the inclined portion 23.

[0094] Thereafter, magnetic foreign matter is attracted and removed from the powder or granular material by the magnetic fields of the multiple magnetic members 30, 31, 32, 33, 34. That is, the magnetic force of the magnets 60, 60 arranged adjacent to each other inside the magnet case 50 acts on the yoke 65, making the yoke 65 an attracting portion, and the portion of the magnet case 50 where the yoke 65 is located becomes an attracting surface, making it possible to attract magnetic foreign matter by this attracting surface.

[0095] In the present invention, the wall portions 51 of each magnet case 50 constituting the magnetic members 30, 31, 32, 33, and 34 are configured to be arranged at a predetermined interval S from the axis C of the casing 20 toward the inner circumferential surface 20a (see Figure 2).

[0096] Therefore, the walls 51 of the magnet cases 50 of the magnetic members 30, 31, 32, 33, and 34 can be arranged densely over a wide area within the casing 20 to an extent that powder and granular materials and the like can pass through, and the walls 51 of the magnet cases 50 can be easily arranged close to the inner circumferential surface 20a of the casing 20, making it difficult for dead space to occur on the inner periphery of the casing. As a result, it is possible to reduce the amount of magnetic foreign matter attracted and leaking from the powder and granular materials and the like.

[0097] Furthermore, since the magnet case 50 has a wall portion 51 that extends continuously in the circumferential direction of the casing 20, the magnetic members 30, 31, 32, 33, and 34 can be structured so that there are no ends where the magnetic field is weak (for example, a structure in which the magnet case of the magnetic members is ring-shaped), or even if there are ends of the magnetic members, the ends can be positioned as close as possible to the inner surface of the casing.

[0098] In the former case, the number of locations where suction leakage occurs can be reduced, and in the latter case, suction leakage can be made less likely to occur at the ends of the magnetic member compared to, for example, a case where the magnetic member has a linear structure.

[0099] Therefore, the remover 10 can reduce the amount of magnetic foreign matter adsorbed and leaked from the powder or fluid.

[0100] Furthermore, as described above, the magnetic member can be configured without any ends where the magnetic field is weak, or even if the magnetic member has ends, these ends can be positioned as close as possible to the inner peripheral surface of the casing, making it possible to realize a removal device with little adsorption leakage with a relatively simple structure. As a result, the manufacturing cost of the removal device can be reduced and the management and maintenance of the removal device can be made easier.

[0101] In addition, in this embodiment, the magnetic members 30, 31, 32, 33, and 34 have a wall portion 51 of each magnet case 50 that forms a continuous ring in the circumferential direction, and have multiple members of similar shapes but different outer dimensions, and are arranged inside the casing 20 in a multiple ring shape (see Figure 2).

[0102] According to the above embodiment, the wall portion 51 of each magnet case 50 of the magnetic members 30, 31, 32, 33, and 34 has the above structure, which makes it easier to manufacture the magnetic members and reduces the cost of the entire removal device. Furthermore, by appropriately adjusting the shape and number of the magnetic members, it becomes possible to flexibly respond to changes in the size and shape of the internal space of the casing, thereby increasing versatility.

[0103] Furthermore, the wall portion 51 of each magnet case 50 of the magnetic members 30, 31, 32, 33, and 34 forms a ring shape without any breaks in the circumferential direction, so there are no axial ends where the magnetic field is weak, as in the linear magnet bar described in Patent Document 1. In other words, each of the magnetic members 30, 31, 32, 33, and 34 can be designed to have a structure without any areas where the magnetic field is weak, which can further reduce the attraction and leakage of magnetic foreign matter from powder and granular materials, etc.

[0104] In addition, in this embodiment, the casing 20 is formed so that the inner peripheral dimension on the discharge port side (not shown) is smaller than the inner peripheral dimension on the inlet 25 side, and one magnetic member 30 is arranged in the inner part of the casing 20 near the discharge port, spaced apart from the inner peripheral surface 20a of the casing 20 (here, the magnetic member 30 is arranged near the tip of the extending direction of the inclined portion 23 of the casing 20), and magnetic members 31, 32, 33, and 34, which have larger outer dimensions than the magnetic member 30, are arranged along the inner peripheral surface 20a of the casing 20 and spaced apart from the inner peripheral surface 20a of the casing 20.

[0105] According to the above-described embodiment, since the multiple magnetic members 30, 31, 32, 33, and 34 are arranged relative to the casing 20 in the above-described layout, it is possible to make it less likely that dead space, where the magnetic field does not reach, will be created on the inner periphery of the casing 20, and it is possible to reduce the adsorption and leakage of magnetic foreign matter from powder and granular materials, etc., introduced through the inlet 25 of the casing 20 and discharged through the outlet (not shown).

[0106] Furthermore, as in the second modified example shown in Figures 7 and 8, when multiple magnetic members 30A, 31A, 32A, 33A, and 34A each having an angular ring shape are arranged in the casing 20 so as to form multiple rings when the removal device 10 is viewed from a planar direction, and the yoke 65A located between the magnet 60 located at the corner 54 of the magnet case 50 and another magnet 60 adjacent to the magnet 60 is in the shape of an expandable spring, the following effects are achieved.

[0107] In other words, when the magnet case 50 is a square ring, gaps are likely to form between the magnet 60 placed at the corner 54 and the adjacent magnet 60, which may cause the yoke placed between them to move slightly, preventing the adhesive force from the yoke from being exerted stably.

[0108] In contrast, according to the above embodiment, the magnet 60 located at the corner 54 of the polygonal ring-shaped magnet case 50 and the yoke 65A located between the other magnets 60 are in the form of an expandable spring, so that the yoke 65A can be positioned at the corner 54 of the magnet case 50 with less risk of movement, and the adhesive force from the yoke 65A can be stably exerted.

[0109] Furthermore, when the plurality of magnetic members 30, 31, 32, 33, and 34 are connected to one another via the holding member 70, as in the third modified example shown in FIGS. 9 and 10, the following effects are achieved.

[0110] In other words, multiple magnetic members 30, 31, 32, 33, 34 are connected to each other via holding member 70 to form a single assembly as a whole, so that multiple magnetic members 30, 31, 32, 33, 34 can be placed inside casing 20 at one time, and multiple magnetic members 30, 31, 32, 33, 34 can also be removed from inside casing 20 at one time.

[0111] As a result, the ease of arranging the magnetic members inside the casing and the ease of removing the magnetic members from inside the casing are improved. Furthermore, by supporting each of the magnetic members 30, 31, 32, 33, and 34 with the holding member 70, the entire assembly can be reinforced.

[0112] The embodiments shown in FIGS. 1, 6 and 11 can also provide the same effects as those described above (improved ease of installation and removal, and reinforcement of the entire assembly).

[0113] Furthermore, as shown in Figures 1, 6, 10 and 11, the holding members 70, 70A and 70B hold the multiple magnetic members 34, 33, 32, 31 and 30 in a spaced-apart relation to the inner surface 20a of the casing 20 while maintaining a predetermined layout.

[0114] This provides the following effect: If the magnetic member is in contact with the inner peripheral surface of the casing, there is a risk that powder or granular material may accumulate at the contact area, which may hinder the passage of the powder or granular material through the magnetic member.

[0115] However, in the case of this embodiment, as described above, the magnetic members 30, 31, 32, 33, and 34 are held at a distance from the inner surface 20a of the casing 20 via the holding members 70, 70A, and 70B, thereby preventing the accumulation of powder and granular materials between the inner surface 20a of the casing 20 and the outer periphery of the magnetic members, and allowing the powder and granular materials to pass smoothly through the gap between the inner surface 20a of the casing 20 and the outer periphery of the magnetic members, thereby further reducing the amount of magnetic foreign matter that is adsorbed and leaks from the powder and granular materials.

[0116] (Second embodiment of magnetic foreign matter removal device) 12 to 14 show a second embodiment of the magnetic foreign matter remover according to the present invention (a structure in which the magnetic member has a spiral shape). Note that parts that are essentially the same as those in the previous embodiment are given the same reference numerals and their description will be omitted.

[0117] As shown in FIGS. 12 and 13, a magnetic foreign matter remover 10A (hereinafter simply referred to as "removal device 10A") in this embodiment has the following configuration.

[0118] That is, the casing 20 in this removal device 10A is formed so that the inner peripheral dimension on the discharge port side (not shown) is smaller than the inner peripheral dimension on the inlet 25 side, and the wall portion 51 of the magnet case 50 of the magnetic member 36 has a spiral shape that is continuously wound in a spiral shape along the axis C of the casing 20, and is configured to be arranged along the inner peripheral surface 20a of the casing 20.

[0119] The magnetic member 36 is held by the holding member 70 in a state spaced apart from the inner circumferential surface 20a of the casing 20 while maintaining its spiral shape.

[0120] As shown in Figures 12 and 14, the wall portion 51 of the magnet case 50 has a shape in which one end 52 located on the inlet 25 side of the casing 20 has an expanded diameter, and the diameter gradually decreases toward the other end 53 located on the outlet side (not shown) of the casing 20, and the wall portion 51 is continuously wound in a spiral shape along the axis C of the casing 20.

[0121] Furthermore, the heights of one end 52 and the other end 53 of the spiral wall 51 of the magnet case 50 are misaligned in the direction along the axis C of the casing 20. In other words, the heights of one end 52 and the other end 53 of the wall 51 do not match in the direction of the winding axis, but are different heights.

[0122] Furthermore, the wall portion 51 of the magnet case 50 is wound in a spiral shape, extending continuously from one end 52 to the other end 53 without any divided or cut portions, and when the removal device 10A is viewed from the direction of the axis C of the casing 20 (which can also be said to be viewed from the direction of the winding axis of the magnetic member itself, or from the planar direction of the removal device 10A), it has a circular spiral shape with circular outer and inner circumferences (see Figure 13).

[0123] That is, the spiral wall portion 51 of the magnet case 50 has an outer peripheral surface and an inner peripheral surface that are wound while describing a curved surface in the shape of a substantially circular arc.

[0124] As shown in FIG. 12, one end 52 side and the other end 53 side of the wall portion 51 of the magnet case 50 are wound flat so as to be perpendicular to the axis C of the casing 20.

[0125] As shown in range B in Figure 12, from the axis C of the casing 20 toward the inner surface 20a of the casing 20, the first winding portion 55a (winding portion on the other end 53 side), the second winding portion 55b, the third winding portion 55c, the fourth winding portion 55d, the fifth winding portion 55e, the sixth winding portion 55f, the seventh winding portion 55g, and the eighth winding portion 55h (winding portion on the one end 52 side) that constitute the wall portion 51 of the magnet case 50 are arranged in this order with a predetermined interval S between them.

[0126] That is, the magnet case 50 is configured so that a plurality of wall portions 51 extending continuously in the circumferential direction of the casing 20 are arranged at predetermined intervals S from the axis C of the casing 20 toward the inner circumferential surface 20a.

[0127] 12, the other end 53 of the magnet case 50 of the magnetic member 36 is disposed near the tip of the inclined portion 23 of the casing 20 in the extension direction while being spaced apart from the inner circumferential surface 20a of the casing 20, and the outer circumferential portion of the magnet case 50 from the other end 53 side to the one end 52 side is disposed along the inner circumferential surface 20a of the casing 20 while being spaced apart from the inner circumferential surface 20a. In other words, the outer circumferential portion of the magnetic member 36 ranging from the reduced-diameter other end 53 side to the outer periphery of the expanded-diameter one end 52 side is disposed along the inner circumferential surface 20a of the casing 20 while being spaced apart.

[0128] The wall portion 51 of the magnet case 50 of the magnetic member 36 described above is wound spirally with its outer and inner circumferences forming arc-shaped curved surfaces, but may also be configured as shown in FIG.

[0129] 15, when viewed from the direction of the winding axis (when viewed from a planar direction), the magnetic member 37 of the modified example of the second embodiment has a square spiral shape with a plurality of straight line portions bent at corners 54. Specifically, the magnet case 50 constituting the magnetic member 37 has a substantially square spiral shape with four corners 54, and each corner 54 is slightly rounded.

[0130] In the second embodiment, the wall portion 51 of the magnet case 50 has a continuously wound spiral shape, which improves the workability when placing the magnetic member 36 inside the casing 20 and also improves the workability when removing the magnetic member 36 from inside the casing 20.

[0131] Furthermore, when the casing 20 has a structure (hopper structure) in which the casing 20 widens upward and narrows downward, it is possible to further reduce the occurrence of dead space on the inner peripheral surface of the casing.

[0132] Furthermore, one end 52 side and the other end 53 side of the magnet case 50 have a flat shape wound so as to be perpendicular to the axis C of the casing 20, which makes it easy to hold the magnetic member 36 in the holding member 70 (the flat shape makes it easy to support and fix the magnetic member 36 to the base frame 71 of the holding member 70, etc.). As a result, the magnetic member 36 can be installed in a stable position inside the casing 20 via the holding member 70.

[0133] (Third embodiment of magnetic foreign matter removal device) 16 to 22 show a third embodiment of the magnetic foreign matter remover according to the present invention (a structure in which the magnetic member has a spiral shape). Note that parts that are essentially the same as those in the previous embodiment are given the same reference numerals and their description will be omitted.

[0134] 16, a magnetic foreign matter remover 10B (hereinafter simply referred to as "removal device 10B") in this embodiment has the following configuration: A wall portion 51 of a magnet case 50 of a magnetic member 38 in this removal device 10B has a spiral shape that is continuously wound from the axis C of the casing 20 toward the inner peripheral surface 20a of the casing 20.

[0135] As shown in Figures 16 and 17, the magnet case 50 of the magnetic member 38 has one end 52 and the other end 53 of its wall portion 51 positioned at the same height and not misaligned in the direction along the axis C of the casing 20.

[0136] 9 and 10, the spiral-shaped magnetic member 38 is held by a holding member 70B, which is similar to the embodiment shown in Fig. 9 and 10, and is held in a state spaced apart from the inner circumferential surface of the casing while maintaining the spiral shape by the holding member (not shown). Note that in the first modified example shown in Fig. 18 and 19, the second modified example shown in Fig. 20 and 21, and the third modified example shown in Fig. 22, the spiral shape is also maintained by the holding member while being held in a state spaced apart from the inner circumferential surface of the casing.

[0137] Furthermore, the wall portion 51 of the magnet case 50 has one end 52 located radially outward, and extends continuously from this end 52 toward the radial center without being divided or cut, and is wound in a spiral shape with a certain gap between them, so that the other end 53 is positioned in the radial center.

[0138] That is, when the removal device 10B is viewed from the direction of the axis C of the casing 20 (which can also be said to be when viewed from the direction of the winding axis of the magnetic member itself, or when viewed from the planar direction of the removal device 10B), the wall portion 51 of the magnet case 50 has a circular spiral shape in which its outer and inner surfaces are wound while describing approximately arc-shaped curved surfaces.

[0139] As shown in range D in Figure 16, from the axis C of the casing 20 toward the inner surface 20a of the casing 20, the first winding portion 56a (the winding portion on the other end 53 side), the second winding portion 56b, the third winding portion 56c, the fourth winding portion 56d, and the fifth winding portion 56e (the winding portion on the one end 52 side) that constitute the wall portion 51 of the magnet case 50 are arranged in this order with a predetermined interval S between them.

[0140] That is, the magnet case 50 is configured so that a plurality of wall portions 51 extending continuously in the circumferential direction of the casing 20 are arranged at predetermined intervals S from the axis C of the casing 20 toward the inner circumferential surface 20a.

[0141] 18 and 19 show a first modified example of the third embodiment.

[0142] The magnetic member 39 of this first modified example is basically spiral-shaped with an arc-shaped circumferential surface, similar to the magnetic member 38 shown in Figures 16 and 17, but it also has a roughly inverted U-shaped frame shape (which can also be said to be a gate-shaped frame shape) extending from one end 52 to the other end 53 of the magnet case 50, with a handle 57 attached.

[0143] In other words, the handle 57 has a gripping portion 57a extending a predetermined length and a pair of connecting portions 57b, 57b hanging parallel to each other from both longitudinal ends of the gripping portion 57a, and one connecting portion 57b is joined to one end 52 of the magnet case 50 by welding or the like, and the other connecting portion 57b is joined to the other end 53 of the magnet case 50, so that the handle 57 is erected (attached) to the magnet case 50.

[0144] 20 and 21 show a second modified example of the third embodiment.

[0145] 16 to 19, the magnetic member 40 of this second modified example is spiral-shaped, similar to the magnetic members 38 and 39 shown in Figures 16 to 19, and further has a structure in which a magnet 58 is fixed to the other end 53 located in the radial center portion of the magnet case 50. The magnet 58 also has a cylindrical base 58a and a conical tip 58b connected to one end of the base 58a.

[0146] FIG. 22 shows a third modified example of the third embodiment.

[0147] The magnetic member 41 of this third modified example has a structure in which one end 52 of the magnet case 50 is joined by welding or the like to a radially adjacent portion of the magnet case 50.

[0148] In the magnetic members shown in Figures 16 to 22, the magnet case has a circular spiral shape, but it may also have a substantially rectangular spiral shape, as in the modified example of the second embodiment shown in Figure 15.

[0149] In the third embodiment, the wall portion 51 of the magnet case 50 has a continuously wound spiral shape, which improves the workability when placing the magnetic member 36 inside the casing 20 and also improves the workability when removing the magnetic member 36 from inside the casing 20. In addition, this is easy to use when the casing has a structure like a transfer pipe.

[0150] 18 and 19 , when a handle 57 is attached to the magnet case 50, an operator can grip the handle 57 to handle the magnetic member 39, improving handleability. As a result, it becomes easier to arrange the magnetic member 39 inside the casing 20 and to remove the magnetic member 39 from inside the casing 20.

[0151] 20 and 21, when the magnet 58 is fixed to the other end 53 located in the radial center portion of the magnet case 50, it becomes easier to capture magnetic foreign matter that attempts to pass through the radial center portion of the magnetic member 40. As a result, it is possible to further reduce the amount of magnetic foreign matter that is attracted and leaks from powder or granular material.

[0152] Furthermore, when one end 52 of the magnet case 50 is joined to a radially adjacent portion of the magnet case 50 by welding or the like, as in the magnetic member 41 of the third modified example shown in Figure 22, it becomes easier to maintain the spiral shape of the magnetic member 41, and the shape retention of the magnetic member 41 can be improved.

[0153] As a result, when placing the magnetic member 41 inside the casing 20, there is no need to modify the shape of the magnetic member 41 or the shape modification work is simple, thereby improving the ease of placing the magnetic member 41 inside the casing.

[0154] It should be noted that the present invention is not limited to the above-described embodiment, and various modified embodiments are possible within the scope of the gist of the present invention, and such embodiments are also included in the scope of the present invention. [Explanation of symbols]

[0155] 10,10A,10B Magnetic foreign matter removal device (removal device) 20 Casing 20a Inner surface 25 entrance 30, 30A, 31, 31A, 32, 32A, 33, 33A, 34, 34A, 35, 36, 37, 38, 39, 40, 41 Magnetic members 50 Magnet Case 51 Wall 52 One end 53 Other end 60 Magnet 61 N pole 62 S pole 65,65A York 70, 70A, 70B Retaining member

Claims

1. A magnetic foreign matter removal device that uses a magnetic field to adsorb and remove magnetic foreign matter from powder or granular material or a fluid containing the magnetic foreign matter, a casing having an inlet for introducing the powder or granular material or fluid and an outlet for discharging the powder or granular material or fluid; a magnetic member disposed inside the casing for attracting and removing the magnetic foreign matter, the magnetic member includes a magnet case and a plurality of magnets housed in the magnet case with like poles facing each other via a yoke, A magnetic foreign matter removal device characterized in that the magnet case has a wall portion that extends continuously circumferentially around the casing, and the wall portion is configured to be arranged at a predetermined interval from an axis that extends from the inlet of the casing toward the outlet and passes through the center of the outlet toward the inner surface of the casing.

2. The magnetic foreign matter removal device of claim 1, wherein the wall portion of the magnet case forms a ring shape without any gaps in the circumferential direction, and the magnetic member has multiple members of similar shapes but different outer dimensions, and is arranged in a multiple ring shape inside the casing.

3. the casing is formed so that an inner circumferential dimension on the outlet side is smaller than an inner circumferential dimension on the inlet side, The magnetic foreign matter removal device of claim 1, wherein the wall portion of the magnet case has a spiral shape that is continuously wound in a spiral shape along the axis, and is arranged along the inner surface of the casing but spaced apart from the inner surface of the casing.

4. 2. The magnetic foreign matter remover according to claim 1, wherein the wall portion of the magnet case has a spiral shape that is continuously wound from the axis of the casing toward the inner peripheral surface of the casing.

5. The magnet case has a shape with corners, A magnetic foreign matter removal device as described in any one of claims 2 to 4, wherein the yoke located between the magnet located at the corner of the magnet case and another magnet adjacent to the magnet is in the form of an expandable spring.

6. 2. The magnetic foreign matter remover according to claim 1, wherein the magnetic member is held in a state spaced apart from the inner peripheral surface of the casing by a holding member.

Images