Magnetic filter and outer tube

Abstract

The present invention provides a magnetic filter and an outer tube that can easily insert and remove a bar magnet relative to an outer tube. The magnetic filter includes: a bar magnet, whose cross-sectional shape perpendicular to the length direction has: a pointed portion with a vertex; and a non-pointed portion other than the pointed portion; and an outer tube, whose cross-sectional shape perpendicular to the length direction has: a pointed portion with a vertex; and a non-pointed portion other than the pointed portion, and the outer tube covers the bar magnet. When the vertex of the bar magnet and the vertex of the outer tube are located on the upper side in the vertical direction, there is a gap between the outer peripheral surface of the bar magnet and the inner peripheral surface of the outer tube that gradually increases from the non-pointed portion toward the vertex.

Description

Technical Field

[0001] The invention relates to a magnetic filter and an outer tube for the magnetic filter. Background Art

[0002] Conventionally, as a magnetic filter for adsorbing and removing foreign matter such as iron-based and stainless-steel-based metal wear powders and metal flakes mixed in various raw materials and products in the form of powder, liquid, or fluid, there is known a magnetic filter such as that disclosed in Patent Document 1. The magnetic filter comprises a bar magnet and an outer tube covering the bar magnet.

[0003] In addition, Patent Document 2 discloses a bar magnet (tear-drop magnet) whose cross-sectional shape is a tear-drop shape for the purpose of improving the magnetic susceptibility of foreign matter.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2006-21134

[0007] Patent Document 2: Japanese Utility Model Registration No. 3132500 Summary of the invention

[0008] Problem that the invention aims to solve

[0009] When a bar magnet having a symmetrical shape in the horizontal and vertical directions, such as a perfect circle in cross section, is inserted or removed from an outer tube, the insertion or removal operation can be performed relatively easily without strictly aligning the relative positional relationship between the bar magnet and the outer tube in the circumferential direction. On the other hand, when the above-mentioned teardrop-shaped magnet is inserted or removed from the outer tube, the insertion or removal operation becomes difficult compared to a bar magnet having a perfect circle in cross section. That is, if the relative positional relationship in the circumferential direction deviates, the teardrop-shaped magnet may not be inserted into the outer tube. In addition, when removing the teardrop-shaped magnet, the teardrop-shaped magnet may be hooked on the inner circumferential surface of the outer tube, making removal difficult.

[0010] The present invention has been made in consideration of such a situation, and an object of the present invention is to provide a magnetic filter and an outer tube that make it easy to insert and remove a bar magnet from an outer tube.

[0011] Solutions for solving problems

[0012] In order to solve the above-mentioned problems, the magnetic filter of the present invention includes: a bar magnet, whose cross-sectional shape perpendicular to the length direction has: a pointed portion with a vertex; and a non-pointed portion other than the pointed portion; and an outer tube, whose cross-sectional shape perpendicular to the length direction has: a pointed portion with a vertex; and a non-pointed portion other than the pointed portion, the outer tube covering the bar magnet, when the vertex of the bar magnet and the vertex of the outer tube are on the upper side in the vertical direction, there is a gap between the outer peripheral surface of the bar magnet and the inner peripheral surface of the outer tube, which gradually increases from the non-pointed portion toward the vertex.

[0013] Furthermore, the outer tube of the present invention is an outer tube used for the magnetic filter.

[0014] Effects of the Invention

[0015] In the magnetic filter of the present invention, the bar magnet can be easily inserted and removed from the outer tube. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is an exploded perspective view showing one embodiment of the magnetic filter of the present invention.

[0017] Figure 2 It is a cross-sectional view of the magnetic filter along the length direction.

[0018] Figure 3 yes Figure 2 Exploded view of the magnetic filter.

[0019] Figure 4 It is along Figure 2 A cross-sectional view taken along line IV-IV.

[0020] Figure 5 It is a perspective view showing a first modified example of the magnetic filter.

[0021] Figure 6 It is a perspective view showing a second modified example of the magnetic filter.

[0022] Figure 7 It is a perspective view showing a third modified example of the magnetic filter.

[0023] Figure 8 It is a perspective view showing a fourth modified example of the magnetic filter.

[0024] Fig. 9 (a) is a partially enlarged cross-sectional view of a magnetic filter having a magnet-side sliding member, Fig. 9 (b) is a partially enlarged cross-sectional view of the magnetic filter having a tube-side sliding member.

[0025] Description of Reference Numerals

[0026] 1. Magnetic filter; 2. Magnet unit; 3. Tube unit; 4. Magnet connecting plate; 5. Tube connecting plate; 7. Gap; 10. Bar magnet; 10a. Pointed portion; 10b. Non-pointed portion; 10c. Vertex; 11. Permanent magnet; 12. Yoke; 13. End plug; 14. Magnet tube; 20. Outer tube; 20a. Pointed portion; 20b. Non-pointed portion; 20c. Vertex; 21. Open end; 22. Closed end; 25. Main body; 26. Flange; 30. Magnet side sliding member; 40. Tube side sliding member; θ 10 , angle (acute angle); θ 20 , angle (acute angle). DETAILED DESCRIPTION

[0027] Embodiments of the magnetic filter and the outer tube according to the present invention will be described with reference to the drawings.

[0028] Figure 1 This is an exploded perspective view showing one embodiment of the magnetic filter of the present invention. Figure 2 It is a cross-sectional view of the magnetic filter 1 along the longitudinal direction. Figure 3 yes Figure 2 Exploded view of the magnetic filter 1. Figure 4 It is along Figure 2 A cross-sectional view taken along line IV-IV.

[0029] The magnetic filter 1 includes a magnet unit 2 and a tube unit 3. When the magnetic filter 1 is used, the magnet unit 2 is inserted into the tube unit 3, so that foreign matter is adsorbed on the surface 3a of the tube unit 3 by the magnetic force of the bar magnet 10. When cleaning the magnetic filter 1, the magnet unit 2 is pulled out from the tube unit 3, so that the influence of the magnetic force on the foreign matter adsorbed on the surface 3a disappears, and the foreign matter is easily removed from the surface 3a.

[0030] The magnet unit 2 is composed of a plurality of bar magnets 10 connected at one end by a magnet connecting plate 4. The bar magnet 10 includes a plurality of permanent magnets 11, a plurality of yokes 12, a pair of end plugs 13, and a magnet tube 14.

[0031] Multiple (in Figure 2 and Figure 3 The permanent magnets 11 are magnetized along the length direction of the bar magnet 10 and are drop-shaped magnets (e.g., neodymium rare earth magnets) with the same poles facing each other in the length direction.

[0032] Multiple (in Figure 2 and Figure 3The yoke 12 is a teardrop-shaped magnetic body having the same surface shape as the permanent magnet 11. The yoke 12 is inserted between adjacent permanent magnets 11 and between the permanent magnet 11 and the end plug 13.

[0033] The end plugs 13 are made of teardrop-shaped non-magnetic metal (for example, stainless steel such as SUS304, SUS316, or SUS316L) having the same surface shape as the permanent magnets 11. The pair of end plugs 13 sandwich the permanent magnets 11 and the yoke 12 at both ends of the bar magnet 10.

[0034] The magnet tube 14 has a hollow shape with a teardrop-shaped cross section perpendicular to the longitudinal direction, and has a size capable of accommodating the arranged permanent magnets 11, yoke 12, and end plugs 13. The magnet tube 14 is made of non-magnetic metal (eg, stainless steel, titanium).

[0035] The permanent magnet 11, the yoke 12 and the end plug 13 are connected to each other in an arranged state, for example, by a shaft (not shown) that passes through them. The ends of the shaft are fixed to the end plug 13 by screws. The arranged permanent magnet 11, the yoke 12 and the end plug 13 are accommodated in the magnet tube 14, and the end plug 13 and the magnet tube 14 are connected by welding, for example. In addition, the permanent magnet 11, the yoke 12 and the end plug 13 can also be accommodated in the magnet tube 14 without being connected by a shaft.

[0036] The cross-sectional shape of the bar magnet 10 perpendicular to the length direction (axial direction) is pointed. Figure 4 As shown, the cross-sectional shape of the bar magnet 10 is a teardrop shape formed by a pointed portion 10a and a non-pointed portion 10b other than the pointed portion 10a. Figure 4 The tip portion 10a is a shape that is symmetrical in the vertical direction. Figure 4 The upper portion of the portion is a pointed portion having a vertex 10c, wherein the vertex 10c is formed by two intersecting lines at an acute angle θ. 10 The non-pointed portion 10b is Figure 4 The lower part of the tip 10a is a semicircular part formed continuously with the two lines. The inclination (angle between the horizontal plane and the inclined plane) of the tip 10a is preferably formed to be greater than the repose angle of the processed object such as powder.

[0037] Each bar magnet 10 is fixed to the magnet connecting plate 4 by means of screws (not shown). The screws can be fixed in two states: a temporary fixing state and a formal fixing state. The temporary fixing state is a state in which a plurality of bar magnets 10 are temporarily fixed to the magnet connecting plate 4, and is a state in which the bar magnets 10 are supported only by screws, but are fixed with clearance relative to the magnet connecting plate 4. The formal fixing state is a state in which the bar magnets 10 are fixed to the magnet connecting plate 4 by means of threads by further tightening the screws from the temporary fixing state, so as to become a state when the magnetic filter 1 is used, that is, a firmly fixed state.

[0038] The tube unit 3 is composed of a plurality of outer tubes 20 connected at one end (closed end 22) by a tube connecting plate 5. The outer tube 20 is a hollow tubular member having an open end 21 at one end and a closed end 22 at the other end, and covers the outer peripheral surface 10d of the bar magnet 10. The outer tube 20 has a body 25 and a flange 26.

[0039] The main body 25 is a hollow tubular member having a teardrop-shaped cross section perpendicular to the longitudinal direction. The main body 25 is made of non-magnetic metal (eg, stainless steel, titanium).

[0040] The flange 26 is provided to move foreign matter attracted to the outer tube 20 to a place without a magnetic field and separate it from the magnet.

[0041] Each outer tube 20 can be connected to the tube connecting plate 5 in a temporary fixed state and a permanent fixed state by screws (not shown). The temporary fixed state and the permanent fixed state are the same as those described in the magnet unit 2, so the description is omitted here.

[0042] The outer tube 20 is similar to the bar magnet 10, and the cross-sectional shape perpendicular to the length direction is a pointed shape. That is, the cross-sectional shape of the outer tube 20 is a teardrop shape formed by the pointed portion 20a and the non-pointed portion 20b other than the pointed portion 20a, and has a Figure 4 The tip portion 20a is a shape that is symmetrical in the vertical direction. Figure 4 The upper portion of the portion is a pointed portion having a vertex 20c, wherein the vertex 20c is formed by two intersecting lines at an acute angle θ. 20 The non-pointed portion 20b is Figure 4The lower part of the semicircular part is formed continuously with these two lines. It is preferred that the inclination of the pointed portion 20a (the angle between the horizontal plane and the inclined plane) is formed to be greater than the repose angle of the processed object such as powder. When the vertices 10c and 20c are located on the upper side in the vertical direction, there is a gap 7 between the outer peripheral surface 10d of the bar magnet 10 and the inner peripheral surface 20d of the outer tube 20, which gradually increases from the non-pointed portion 10b and 20b toward the vertices 10c and 20c of the pointed portion 10a and 20a. That is, the angle θ of the vertex 10c of the bar magnet 10 is 10 (The angle of the outer peripheral surface 10d) is greater than the angle θ of the vertex 20c of the outer tube 20. 20 (The angle of the inner peripheral surface 20d) is large.

[0043] Here, in the magnetic filter 1, the operability when inserting the magnet unit 2 into the tube unit 3 may be reduced compared with, for example, a magnetic filter whose cross-sectional shape perpendicular to the longitudinal direction is a perfect circle. That is, the cross-sectional shape of the bar magnet 10 and the outer tube 20 is a teardrop shape, and therefore, unless the relative positional relationship in the circumferential direction is appropriately aligned, the bar magnet 10 cannot be inserted into the open end 21 of the outer tube 20. In addition, when removing, the outer peripheral surface 10d of the bar magnet 10 may be hooked on the inner peripheral surface 20d of the outer tube 20, and removal may become difficult.

[0044] In particular, for the magnet unit 2 formed by connecting a plurality of bar magnets 10 and the tube unit 3 formed by connecting a plurality of outer tubes 20, it is necessary to adjust the positional relationship of the plurality of bar magnets 10 in the circumferential direction at the same time, which makes the insertion and removal operations difficult. In addition, the bar magnets 10 sometimes deform in the longitudinal direction due to the mutual attraction or repulsion of the magnetic forces of each other. In addition, it is technically difficult to form the outer tube 20 into a teardrop shape with high precision, and the outer tube 20 may also be distorted during manufacturing.

[0045] On the other hand, as described above, in the magnetic filter 1 of the present embodiment, the angle θ of the pointed portion 10a of the bar magnet 10 is 10 The angle θ of the tip portion 20a of the outer tube 20 is greater than 20The bar magnet 10 is large and has a gap 7 that gradually increases from the non-pointed portion 10b, 20b toward the apex 10c, 20c of the pointed portion 10a, 20a. As a result, when inserting and removing the bar magnet 10, it is not necessary to strictly align the relative positional relationship between the bar magnet 10 and the outer tube 20 in the circumferential direction, which can make the insertion and removal operation particularly easy. In addition, due to the provision of the gap 7 between the outer circumferential surface 10d of the bar magnet 10 and the inner circumferential surface 20d of the outer tube 20, the attraction force of foreign matter is greatly reduced. However, from the perspective of attracting foreign matter, it is originally preferred that the magnetic force of the teardrop-shaped bar magnet 10 is weakest near the apex 10c, and the magnetic force increases from the pointed portion 10a to the non-pointed portion 10b (the magnetic force is strongest on the lower side in the vertical direction). Therefore, even if the gap 7 is provided, foreign matter can be properly attracted.

[0046] In addition, the connecting plates 4 and 5 can connect the bar magnet 10 and the outer tube 20 in a temporarily fixed state and a formally fixed state. During insertion, the bar magnet 10 and the magnet can be connected with the connecting plate 4 with play in the temporarily fixed state, and the outer tube 20 and the tube connecting plate 5 can be connected with play. As a result, fine adjustment of the bar magnet 10 and the outer tube 20 can be performed during insertion. The insertion operability can be further improved by complementing the effect of the gap 7. In addition, by tightening the screws after insertion to firmly fix them, the bar magnet 10, the outer tube 20 and the connecting plates 4 and 5 are firmly fixed to each other when the magnetic filter 1 is used.

[0047] Several embodiments of the present invention have been described, but these embodiments are provided as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other ways, and various omissions, substitutions, and changes can be made without departing from the scope of the invention. These embodiments and their variations are included in the scope and spirit of the invention, and are included in the invention described in the claims and the scope of their equivalents.

[0048] For example, as long as there is a non-pointed portion, the cross-sectional shape of the bar magnet and the outer tube perpendicular to the length direction can be any shape, and in addition to a teardrop shape, it can also be a diamond, triangle, etc. The non-pointed portion does not need to be formed in a curved shape, but can be formed in a straight line.

[0049] Regarding the outer tube, an example in which one end is the open end 21 and the other end is the closed end 22 has been described, but both ends may be open ends.

[0050] In the above-mentioned embodiment, an example is described in which the bar magnet and the outer tube are connected at one end by a connecting plate, but it is also possible to Figure 5 and Figure 6As shown in FIG. 1 , at least one of the bar magnet 10 and the outer tube 20 is not connected, but is a single body. In addition, the example in which the tube units are connected at the closed end side by the connecting plate is described, but it is also possible to Figure 7 As shown in the figure, it is connected at the open end 21 side, and it can also be connected as shown in the figure. Figure 8 As shown, both ends, the open end 21 side and the closed end 22 side, are connected.

[0051] Although the example in which the magnet unit 2 and the pipe unit 3 can be fixed to the connection plates 4 and 5 in a temporary fixed state and a permanent fixed state has been described, the present invention is not limited thereto and the magnet unit 2 and the pipe unit 3 may be fixed firmly in advance by welding or the like.

[0052] In order to further improve the insertion and removal operability, a sliding member may be provided at the tip of the bar magnet. Fig. 9 (a) is a partially enlarged cross-sectional view of the magnetic filter 1 having a magnet-side sliding member 30. The bar magnet 10 has a magnet-side sliding member 30 on the side of the top end 31 on the side of the open end inserted into the outer tube 20 in the longitudinal direction, and the magnet-side sliding member 30 makes the top end 31 slide relative to the inner circumferential surface 20d of the outer tube 20 when plugging and unplugging relative to the open end. The magnet-side sliding member 30 is fixed to the top end 31 by a screw 35, for example. When the bar magnet 10 is inserted into the outer tube 20, the magnet-side sliding member 30 acts by guiding the top end 31 toward the open end. In addition, when removing, the magnet-side sliding member 30 also makes the bar magnet 10 slide well relative to the outer tube 20. As a result, the plug-in and pull-out operability can be improved in conjunction with the effect of the gap 7.

[0053] In addition, the sliding member may be provided on the outer tube 20 . Fig. 9 (b) is a partially enlarged cross-sectional view of the magnetic filter 1 having the tube side sliding member 40. When the bar magnet 10 is inserted or pulled out relative to the open end 21, the tube side sliding member 40 slides the outer peripheral surface 10d of the bar magnet 10. The tube side sliding member 40 is an annular thin-walled member having a certain width in the longitudinal direction. The tube side sliding member 40 is fixed to the inner peripheral surface 20d on the side of the open end 21 (the other end side) by, for example, an adhesive.

[0054] These sliding members 30 and 40 can be formed of resin (for example, ultra-high molecular weight polyethylene or Teflon (registered trademark)).

Claims

1. A magnetic filter comprising: A bar magnet, the cross-sectional shape of which is perpendicular to the length direction has: a pointed portion having an apex; and a non-pointed portion other than the pointed portion; as well as an outer tube, the cross-sectional shape of which is perpendicular to the length direction having: a pointed portion having a vertex; and a non-pointed portion other than the pointed portion, the outer tube covering the bar magnet, When the vertex of the bar magnet and the vertex of the outer tube are located on the upper side in the vertical direction, a gap gradually increases from the non-pointed portion toward the vertex between the outer peripheral surface of the bar magnet and the inner peripheral surface of the outer tube.

2. The magnetic filter according to claim 1, wherein The angle of the apex of the bar magnet is greater than the angle of the apex of the outer tube.

3. The magnetic filter according to claim 1 or 2, wherein: The magnetic filter also includes a tube connecting plate, which can fix the multiple outer tubes in a formal fixed state and a temporary fixed state, wherein the temporary fixed state is a state of being fixed with a clearance compared to the formal fixed state, and the tube connecting plate connects the multiple outer tubes at one end side of the outer tube in the length direction or at one end side and the other end side.

4. The magnetic filter according to claim 1 or 2, wherein: The magnetic filter also includes a magnet connecting plate, which can fix the multiple bar magnets in a formal fixed state and a temporary fixed state. The temporary fixed state is a state of being fixed with a clearance compared to the formal fixed state. The magnet connecting plate connects the multiple bar magnets at one end side in the length direction of the bar magnet.

5. The magnetic filter according to claim 1, wherein The outer tube has an open end at one end side in the length direction for inserting the bar magnet. The bar magnet has a magnet-side sliding member on one end side of the longitudinal direction inserted into the open end, and when the bar magnet is inserted into the open end, the magnet-side sliding member slides the one end relative to the inner peripheral surface of the outer tube.

6. The magnetic filter according to claim 1, wherein The outer tube has an open end for inserting the bar magnet at one end in the longitudinal direction, and has a tube-side sliding member at the one end for sliding the outer peripheral surface of the bar magnet when the bar magnet is inserted into the open end.

7. The magnetic filter according to claim 5 or 6, wherein: The sliding member is formed of resin.

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