Magnetic separator

Abstract

To provide a magnetic separator that can suppress the accumulation of sludge inside the tank. [Solution] The magnet separator 10 includes a tank section 11, a magnet drum 12, a baffle plate 20, a guide plate 21, a magnetic field circulation section 36 formed on the lower side of the magnet drum 12, and a liquid inlet 40. The baffle plate 20 is positioned opposite the liquid inlet 40. The baffle plate 20 is inclined at an angle from its upper end 20a to its lower end 20b such that the distance from the wall section 31 of the tank section 11 increases. The guide plate 21 is positioned between the bottom surface 34 and the inlet-side opening 36a of the magnetic field circulation section 36. The guide plate 21 has a plurality of inclined sections in which the angle with the bottom surface 34 increases in stages from the bottom surface 34 toward the inlet-side opening 36a.

Description

Technical Field

[0001] The present invention relates to a magnetic separator having a magnetic drum for removing magnetic substances contained in a liquid.

Background Art

[0002] When processing a metal material with a machine tool, various liquids such as grinding fluid, cutting fluid, and coolant are used. These liquids are discharged from the machine tool in a state containing foreign substances such as chips and metal powder generated by machining.

[0003] The liquid discharged from the machine tool is reused after separating and removing foreign substances such as chips. Therefore, various devices for collecting the liquid discharged from the machine tool and separating and removing foreign substances from the liquid are known. For example, a magnetic separator is known as a device for separating and removing magnetic substances from a liquid (for example, Patent Document 1).

[0004] One example of a magnetic separator includes a tank portion for storing a liquid containing a magnetic substance, a magnetic drum provided in the tank portion, a squeezing roll that rotates in a direction opposite to the magnetic drum while being in contact with the outer peripheral surface of the magnetic drum, and a scraping plate for scraping off the magnetic substance attached to the outer peripheral surface of the magnetic drum.

[0005] The liquid is supplied to the tank portion, for example, from a liquid inlet opening in the wall portion of the tank portion. When the liquid supplied to the tank portion passes through a magnetic field circulation portion along the outer peripheral surface of the magnetic drum, the magnetic substance contained in the liquid is adsorbed to the outer peripheral surface of the magnetic drum. The magnetic substance thus adsorbed to the outer peripheral surface of the magnetic drum emerges from the liquid surface as the magnetic drum rotates and is scraped off by the scraping plate and discharged to the outside.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

[0007] There is still room for improvement regarding the structure of the magnetic separator. For example, sludge containing magnetic materials and non-magnetic materials such as abrasive particles in the liquid that flows from the liquid inlet into the tank accumulates on the bottom of the tank, and when the amount becomes large, workers need to remove the sludge from the tank. This not only requires labor and time to remove the sludge, but also necessitates temporarily stopping the operation of the magnetic drum. For these reasons, it is desirable to minimize the amount of sludge that accumulates in the tank, and more preferably to prevent sludge from accumulating in the tank at all.

[0008] One of the objectives of this invention is to provide a magnetic separator that can prevent the accumulation of sludge and other materials to be removed inside the tank. [Means for solving the problem]

[0009] A magnet separator according to one embodiment comprises a tank section for containing a liquid containing a magnetic material, a liquid inlet opening in the wall of the tank section for supplying the liquid to the tank section, a magnet drum that rotates about an axis, a baffle plate, and a guide plate. The magnet drum has an outer surface for attracting the magnetic material, and magnets are arranged inside the outer surface. A magnetic field flow section is formed on the lower side of the outer surface of the magnet drum. The liquid flows from the inlet opening to the outlet opening of this magnetic field flow section.

[0010] The baffle plate is positioned inside the tank section, facing the liquid inlet, and has an upper end, a lower end, and both sides. The baffle plate is inclined at an angle such that the distance from the wall section increases from the upper end to the lower end. A bottom side flow path is formed between the lower end of the baffle plate and the bottom surface of the tank section, and a side flow path is formed between the both sides and the side walls of the tank section. The guide plate is positioned between the bottom surface and the inlet-side opening of the magnetic field flow section. The guide plate has a plurality of inclined sections in which the angle with the bottom surface increases in stages from the bottom surface toward the inlet-side opening.

[0011] With respect to the width of the baffle plate, it is preferable that the width of the baffle plate be set such that the sum of the distance from one side wall of the tank section to one side of the baffle plate and the distance from the other side wall to the other side of the baffle plate is 0.3 to 0.5 times the width of the tank section. The guide plate may also have a first inclined surface, a second inclined surface, and a third inclined surface, where the angle with the bottom surface increases in stages from the bottom surface toward the inlet opening. For example, the angle between the first inclined surface and the second inclined surface is in the range of 150° to 160° centered around 155°, and the angle between the second inclined surface and the third inclined surface is in the range of 150° to 160° centered around 155°.

[0012] In the magnet separator of the above embodiment, the guide plate and the curved plate portion for forming the magnetic field flow section may be integrally formed from a single sheet of metal. [Effects of the Invention]

[0013] According to this invention, the accumulation of sludge in the tank portion of the magnetic drum can be suppressed by the baffle plate and the guide plate. [Brief explanation of the drawing]

[0014] [Figure 1]Figure 1 is a perspective view of a magnetic separator according to one embodiment. [Figure 2] Figure 2 is a perspective view showing a partial cross-section of the magnetic separator shown in Figure 1 with the cover removed. [Figure 3] Figure 3 is a plan view of a portion of the magnetic separator, seen from above. [Figure 4] Figure 4 is a cross-sectional view of a portion of the magnet separator along the line F4-F4 in Figure 3. [Figure 5] Figure 5 is a perspective view of the guide plate of the magnetic separator. [Figure 6] Figure 6 is a cross-sectional view of a portion of a magnet separator according to a comparative example. [Modes for carrying out the invention]

[0015] A magnetic separator according to one embodiment will be described below with reference to Figures 1 to 5. Note that this disclosure is merely an example, and the present invention is not limited to the embodiments described below. Modifications that are easily conceivable by those skilled in the art are naturally included within the scope of the disclosure. For clarity, the size, shape, and other characteristics of each part may be schematically represented in the drawings, differing from those of the actual embodiments.

[0016] In this embodiment, a magnetic separator is disclosed for removing mainly magnetic materials from foreign matter contained in liquids such as grinding fluid discharged from machine tools, such as grinding machines. The liquid referred to here includes water-soluble liquids and oil-based liquids. Magnetic materials include, for example, metal powders and metal shavings. Magnetic materials have the property of being attracted by magnetic force.

[0017] FIG. 1 is a perspective view of a magnetic separator 10 according to one embodiment. FIG. 2 is a perspective view showing a part of the magnetic separator 10 in cross section. In the embodiment shown in FIG. 2, a first direction X, a second direction Y, and a third direction Z that are orthogonal to each other are defined. One side Y1 of the second direction Y is referred to as the "front side", and the other side Y2 is referred to as the "rear side". Also, one side Z1 of the third direction Z may be referred to as the "upper side", and the other side Z2 may be referred to as the "lower side".

[0018] As shown in FIGS. 1 and 2, the magnetic separator 10 includes a tank portion 11, a magnetic drum 12 provided in the tank portion 11, a drive portion 13 provided outside the tank portion 11, a throttle roll 14, a scraping plate 15, a baffle plate 20, a guide plate 21, and the like. The baffle plate 20 and the guide plate 21 will be described in detail later.

[0019] The drive portion 13 rotates the magnetic drum 12 and the throttle roll 14. The magnetic drum 12 and the throttle roll 14 are covered by a cover 25 (shown in FIG. 1). FIG. 2 shows a state in which the cover 25 is removed.

[0020] FIG. 3 is a plan view of a part (near the storage portion 11a) of the magnetic separator 10 viewed from above. In a plan view of the magnetic separator 10 viewed from above, the inner region surrounded by the tank portion 11 is the storage portion 11a of the tank portion 11. The tank portion 11 has a front wall portion 30 (shown in FIG. 2), a rear wall portion 31, one side wall 32, the other side wall 33, and a bottom surface 34.

[0021] The tank portion 11 includes a storage portion 11a to which a liquid containing a magnetic substance is supplied, and a liquid chamber 11b (shown in FIG. 2) into which the liquid from which the magnetic substance has been removed flows. A discharge port 11c is formed in the bottom wall of the liquid chamber 11b. A curved plate portion 35 along the outer peripheral surface 12a of the magnetic drum 12 is disposed between the storage portion 11a and the liquid chamber 11b. A magnetic field circulation portion 36 is formed between the outer peripheral surface 12a of the magnetic drum 12 and the plate portion 35.

[0022] A liquid inlet 40 is opened in the rear wall 31 of the tank section 11. A liquid supply pipe 42 is connected to the joint 41 of the liquid inlet 40. Liquid (liquid containing magnetic material) sent through the liquid supply pipe 42 is supplied from the liquid inlet 40 to the inside of the tank section 11 (storage section 11a).

[0023] The magnet drum 12 has a cylindrical portion 50 including an outer circumferential surface 12a for attracting magnetic material. The cylindrical portion 50 rotates in the direction indicated by arrow R1 about an axis A1 (shown in Figure 2) that extends in a first direction X. Axis A1 passes through the center of the shaft 51. The shaft 51 extends in the first direction X and is located at the center of rotation of the magnet drum 12.

[0024] A magnet 52 is positioned inside the magnet drum 12. An example of a magnet 52 is a permanent magnet. The magnet 52 is fixed to a frame member or the like so that it is stationary relative to the rotating cylindrical part 50. The magnetic force generated by the magnet 52 forms a magnetic field region MA on the outer surface 12a of the magnet drum 12, in which magnetic material can be attracted and a non-magnetic field region NMA in which magnetic material can be released.

[0025] Each element constituting the magnetic drum 12, with the exception of the magnet 52, is formed from a non-magnetic material such as stainless steel. Note that each element may also include parts made from metal materials other than stainless steel or resin molded products.

[0026] The squeezing roll 14 is positioned parallel to the magnet drum 12. The squeezing roll 14 is located above the magnet drum 12 and includes a roll body 14a made of an elastic material such as hard rubber. The roll body 14a rotates around an axis 53 parallel to the axis A1 of the magnet drum 12.

[0027] With the outer surface of the squeezing roll 14 and the outer surface 12a of the magnet drum 12 in contact with each other at the contact portion 55, the squeezing roll 14 is rotated by the drive unit 13 in a second direction opposite to that of the magnet drum 12 (indicated by arrow R2 in Figure 2). As a result, the liquid and magnetic material adhering to the outer surface 12a of the magnet drum 12 are squeezed at the contact portion 55, and most of the squeezed liquid flows from the contact portion 55 into the storage portion 11a.

[0028] A scraping plate 15 is provided on the magnet separator 10. The scraping plate 15 is responsible for scraping off magnetic material adhering to the outer surface 12a of the magnet drum 12. The scraping plate 15 is positioned in front of the contact portion 55 in the direction of rotation of the magnet drum 12. Below the scraping plate 15 is a discharge plate 61 which functions as a chute to guide the magnetic material to fall.

[0029] Figure 4 is a cross-sectional view of a portion of the magnet separator 10 along the line F4-F4 in Figure 3. The baffle plate 20 and the guide plate 21 are arranged inside the tank section 11, i.e., in the storage section 11a. First, the baffle plate 20 will be described.

[0030] The baffle plate 20 is positioned inside the tank section 11, facing the liquid inlet 40. The baffle plate 20 has an upper end 20a, a lower end 20b, one side 20c, and the other side 20d. As shown in Figure 4, the baffle plate 20 is substantially flat from the upper end 20a to the lower end 20b. The baffle plate 20 is positioned at an angle θ1 from the upper end 20a to the lower end 20b, such that the distance from the wall section 31 increases. An example of an angle θ1 is preferably 25°. However, the angle θ1 may be 20° or more and less than 30°.

[0031] As shown in Figure 3, when viewing the tank section 11 from above, the width W1 of the baffle plate 20 is greater than the diameter (opening width) of the liquid inlet 40, for example, 110 mm. The distance W3 from one side wall 32 to one side 20c of the baffle plate 20 and the distance W4 from the other side wall 33 to the other side 20d of the baffle plate 20 may be different from each other or the same from each other, depending on the specifications of the magnet separator 10. The width W1 of the baffle plate 20 is set such that the sum of the widths W3 and W4 (W3 + W4) is 0.3 to 0.5 times the width W2 of the tank section 11.

[0032] As shown in Figure 4, the distance H1 from the lower end 20b of the baffle plate 20 to the bottom surface 34 is, for example, 50 mm. A bottom side flow path 70 is formed between the lower end 20b of the baffle plate 20 and the bottom surface 34. Also, as shown in Figure 3, a first side flow path 71 is formed between one side 20c of the baffle plate 20 and one side wall 32 of the tank section. A second side flow path 72 is formed between the other side 20d of the baffle plate 20 and the other side wall 33 of the tank section.

[0033] Next, I will explain the information plate 21. Figure 5 is a perspective view of the guide plate 21 and the plate portion 35. In this embodiment, the guide plate 21 and the curved plate portion 35 for forming the magnetic field flow section 36 are integrally formed from a single sheet metal 80. As shown in Figure 2, the plate portion 35 is positioned downstream of the guide plate 21 (downstream with respect to the direction of liquid flow). The plate portion 35 is connected to the upper end 21b of the guide plate 21.

[0034] As shown in Figure 4, the guide plate 21 is positioned between the bottom surface 34 and the inlet-side opening 36a of the magnetic field circulation section 36. The guide plate 21 has a plurality of inclined surfaces 81, 82, and 83, the angle θ it makes with the bottom surface 34 increasing in stages from the bottom surface 34 toward the inlet-side opening 36a. The guide plate 21 having the inclined surfaces 81, 82, and 83 has a downward-convex shape. The guide plate 21 in this embodiment has three inclined surfaces 81, 82, and 83, but it is sufficient to have two or more inclined surfaces.

[0035] As shown in Figure 5, a first bend 85 is formed between the first inclined surface 81 and the second inclined surface 82, and a second bend 86 is formed between the second inclined surface 82 and the third inclined surface 83. These bends 85 and 86 can be formed, for example, by pressing. The lower end 21a of the guide plate 21 is in contact with the bottom surface 34. The upper end 21b of the guide plate 21 extends toward the opening 36a on the inflow side of the magnetic field circulation section 36, and the upper end 21b is connected to the plate section 35.

[0036] The angle θ2 (shown in Figure 4) between the first inclined surface 81 and the second inclined surface 82 is, for example, 155°. The angle θ3 between the second inclined surface 82 and the third inclined surface 83 is, for example, 155°. These angles θ2 and θ3 are set according to the specifications of the magnet separator 10 and are not limited to 155°. θ2 may be in the range of 150° to 160°. Similarly, θ3 may be in the range of 150° to 160°. The distance H2 (shown in Figure 4) from the bottom surface 34 to the upper end 21b of the guide plate 21 is, for example, 92 mm. The horizontal distance L1 of the guide plate 21 is, for example, 71 mm.

[0037] Next, the operation of the magnetic separator 10 in this embodiment will be described. Liquid containing magnetic material, discharged from the liquid-using section of a machine tool or the like, flows into the storage section 11a from the liquid inlet 40 toward the baffle plate 20, as shown by arrow FL1 in Figure 4. The incoming liquid changes direction due to the baffle plate 20, and the downward-flowing liquid passes through the bottom channel 70 and moves toward the guide plate 21 along the bottom surface 34 at a relatively fast flow velocity, as shown by arrow FL2 in Figure 4.

[0038] A portion of the liquid flowing in from the liquid inlet 40 flows along both sides of the baffle plate 20 through the left and right side passages 71 and 72. That is, a relatively weak flow is generated between one side wall 32 of the tank section 11 and one side 20c of the baffle plate 20, and between the other side wall 33 and the other side 20d of the baffle plate 20.

[0039] As the liquid flowing in from the liquid inlet 40 passes through the bottom channel 70 towards the guide plate 21, a relatively fast-flowing liquid is generated along the bottom surface 34 from near the bottom surface 34 to the guide plate 21. The flow along the bottom surface 34 towards the guide plate 21 rises along the sloped sections 81, 82, and 83 and flows into the magnetic field circulation section 36 from the inlet opening 36a. Magnetic materials and non-magnetic sludge in the liquid flow into the magnetic field circulation section 36, carried by this relatively fast liquid flow from the bottom surface 34 along the guide plate 21. A portion of the liquid rises along the guide plate 21 towards the liquid surface Q1, as shown by arrow FL3 in Figure 4, and then generates a flow towards the baffle plate 20, as shown by arrow FL4.

[0040] The liquid containing magnetic material that flows into the magnetic field circulation section 36 flows along the outer surface 12a of the magnet drum 12 toward the outlet opening 36b, as shown by arrow FL5 in Figure 2. As the liquid containing magnetic material flows through the magnetic field circulation section 36, the magnetic material in the liquid is attracted to the magnetic field region MA of the magnet drum 12. The liquid from which the magnetic material has been removed moves to the liquid chamber 11b, as shown by arrow FL6 in Figure 2, and is discharged from the outlet 11c.

[0041] As the magnet drum 12 rotates in a first direction (indicated by arrow R1 in Figure 2), the magnetic material adsorbed to the outer surface 12a of the magnet drum 12 moves out of the liquid surface Q1 as the magnet drum 12 rotates, towards the squeezing roll 14, and reaches the contact area 55. The magnetic material and liquid adhering to the magnet drum 12 are squeezed off at the contact area 55. Most of the squeezed-off liquid falls from the contact area 55 into the storage area 11a. The magnetic material adhering to the magnet drum 12 is scraped off by the scraping plate 15 as the magnet drum 12 rotates. The scraped-off magnetic material falls along the discharge plate 61 and is recovered.

[0042] Non-magnetic materials in the liquid that flow into the storage section 11a from the liquid inlet 40 flow into the magnetic field circulation section 36, carried by the relatively fast liquid flow along the bottom surface 34 and guide plate 21, similar to magnetic materials. This prevents non-magnetic materials in the liquid from remaining in the storage section 11a. The non-magnetic materials that flow into the magnetic field circulation section 36 move to the liquid chamber 11b without being attracted to the magnet drum 12 and are discharged from the outlet 11c along with the liquid. The non-magnetic materials in the liquid discharged from the outlet 11c are sent to a filtration facility for removal of non-magnetic materials.

[0043] [Comparative Example] Figure 6 is a cross-sectional view of a part of the comparative example magnet separator 90. A baffle plate 92 and a guide plate 93 are arranged inside the tank portion 91 of the comparative example magnet separator 90. The comparative example baffle plate 92 has an inclined portion 92c that extends at an angle θ4 from the upper end 92a to the lower end 92b, and a vertical portion 92d that extends downward from the inclined portion 92c. The distance H3 from the bottom surface 91a of the tank portion 91 to the lower end 92b of the baffle plate 92 is 50 mm.

[0044] The guide plate 93 of the comparative example has a shape that extends diagonally from the bottom surface 91a at an angle θ5. An example of an angle θ5 is 105°. The height H4 of the guide plate 93 is 92 mm. The horizontal distance L2 of the guide plate 93 is 25 mm. The magnetic separator 90 of the comparative example generates a relatively slow flow along the bottom surface 91a, a flow that hits the guide plate 93 and moves toward the liquid surface Q2, and a flow that moves from the guide plate 93 toward the baffle plate 92, as shown by the arrows in Figure 6.

[0045] In the comparative example, the magnetic separator 90 had a problem in that the flow from the baffle plate 92 along the bottom surface 91a toward the guide plate 93 was relatively slow, resulting in a large accumulation of sludge on the bottom surface 91a. In particular, a large amount of sludge was observed accumulating near both sides in the width direction of the guide plate 93.

[0046] In contrast, the magnetic separator 10 according to this embodiment suppresses the accumulation of sludge on the bottom surface 34 of the storage section 11a, virtually eliminating the need for workers to remove sludge from the tank section 11.

[0047] In implementing the magnet separator according to the present invention, the specific configurations of each element constituting the magnet separator, including the magnet drum, baffle plate, and guide plate, can be changed in various ways. Various embodiments can be formed by appropriately combining the multiple components disclosed in the above embodiments. For example, some components may be removed from all the components shown in the embodiments, or different components may be appropriately combined. [Explanation of Symbols]

[0048] 10...Magnetic separator, 11...Tank section, 12...Magnetic drum, 12a...Outer surface, 20...Baffle plate, 21...Guide plate, 31...Wall section, 34...Bottom surface, 35...Plate section, 36...Magnetic field flow section, 36a...Inlet opening, 40...Liquid inlet, 70...Bottom side flow path, 71,72...Side flow path, 80...Sheet metal, 81,82,83...Sloping section.

Claims

1. A tank section for containing a liquid containing a magnetic material, A liquid inlet is provided, which is open in the wall of the tank section and supplies the liquid to the tank section. A magnet drum having an outer surface for attracting the magnetic material, with a magnet positioned inside the outer surface, and rotating about an axis, A magnetic field flow section is formed on the lower side of the outer surface of the magnet drum, through which the liquid flows from the inlet opening to the outlet opening, A baffle plate is positioned inside the tank section opposite the liquid inlet, having an upper end, a lower end, and both sides, inclined at an angle from the upper end to the lower end such that the distance from the wall section increases, forming a bottom side passage between the lower end and the bottom surface of the tank section, and forming side passages between the both sides and the side walls of the tank section. A guide plate is positioned between the bottom surface and the inlet-side opening of the magnetic field circulation section, and has a plurality of inclined surfaces, the angle between the bottom surface and the inlet-side opening increasing in stages from the bottom surface toward the inlet-side opening, A magnetic separator characterized by having the following features.

2. In the magnetic separator according to claim 1, A magnet separator in which, with respect to the width of the baffle plate, the sum of the distance from one side wall of the tank section to one side of the baffle plate and the distance from the other side wall to the other side of the baffle plate is 0.3 to 0.5 times the width of the tank section.

3. In the magnetic separator according to claim 1, The aforementioned guide plate, A magnet separator having a first inclined surface, a second inclined surface, and a third inclined surface, the angle between the bottom surface and the inlet opening increasing in stages from the bottom surface toward the opening on the inlet side, wherein the angle between the first inclined surface and the second inclined surface is in the range of 150° to 160°, and the angle between the second inclined surface and the third inclined surface is in the range of 150° to 160°.

4. In the magnetic separator according to claim 1, A magnet separator in which the guide plate and the curved plate portion for forming the magnetic field circulation section are integrally formed from a single sheet of metal.

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