Suspension stirring device

Abstract

The objectives are to reduce the likelihood of clumping, shorten the time required to add powder to the liquid and the time required for dispersion and dissolution of powder in the liquid, and to be able to handle a wide variety of powders. [Solution] A suspension stirring device for stirring powder and liquid, A tank into which the powder and the liquid are introduced, The tank comprises a cylindrical slit ring provided at the bottom of the tank and having multiple windows around its entire circumference, and an agitation blade having inner blades located inside the slit ring and capable of rotating individually, The suspension stirring device is characterized in that the inner vane has a suction vane capable of generating a vortex flow at the top and a centrifugal plate capable of generating a centrifugal flow at the bottom, and the centrifugal plate is attached in a replaceable manner.

Description

Technical Field

[0001] The present invention relates to a suspension stirring device for a suspension in which powder and liquid are mixed.

Background Art

[0002] In cosmetics and the like, there are products produced by mixing powder and liquid. However, when mixing powder into liquid, it often tends to form agglomerated lumps (powder clusters), and dispersion and dissolution are often difficult.

[0003] Conventionally, a stirring device that stirs powder and liquid with a disperser blade is often used. This stirring device has a configuration in which a disperser blade provided on a rotating shaft suspended from above rotates in a substantially cylindrical tank to stir the raw materials.

[0004] Patent Document 1 describes the configuration of a stirring device that stirs powder with a disperser blade.

Prior Art Documents

Patent Documents

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2024-142956

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, the stirring device described in Patent Document 1 has a problem that the powder tends to form agglomerated lumps, and there is a risk that the time until the powder is dispersed and dissolved in the liquid becomes long.

[0007] An object of the present invention is to solve the above problems, make it difficult for the powder to form agglomerated lumps, shorten the powder charging time and the powder dispersion / dissolution time in the liquid, and cope with various types of powders.

Means for Solving the Problems

[0008] To solve the above problems, the present invention provides a suspension stirring device for stirring powder and liquid, A tank into which the powder and the liquid are introduced, The tank comprises a cylindrical slit ring provided at the bottom of the tank and having multiple windows around its entire circumference, and an agitation blade having inner blades located inside the slit ring and capable of rotating individually, The present invention provides a suspension stirring device characterized in that the inner vane has a suction vane capable of generating a vortex flow at the top and a centrifugal plate capable of generating a centrifugal flow at the bottom, and the centrifugal plate is provided to be replaceable.

[0009] This configuration makes it less likely for powder to form clumps, shortens the time required to add powder to the liquid and the time required for dispersion and dissolution of powder in the liquid, and allows for handling of a wide variety of powders by making the centrifugal plate replaceable. Generally, when powder is added to a liquid all at once, it is difficult for the powder to disperse and tends to form clumps, but the rotation of the slit ring and inner blades shortens the time required to add powder to the liquid and the time required for dispersion and dissolution of powder in the liquid.

[0010] In a suspension stirring device, the centrifugal plate may be attached to the suction blades by screw fastening.

[0011] This configuration allows the centrifugal plate to be removed and replaced by releasing the screws, while also keeping the number of parts low, resulting in lower costs, and making cleaning easy.

[0012] The suspension stirring device may be configured such that the suction blades are replaceable by inserting their pins into the holes of the centrifugal plate.

[0013] This configuration reduces the time required to tighten screws using tools, allows for easy replacement of centrifugal plates, and eliminates the need to clean the screw threads, thus improving ease of cleaning.

[0014] In a suspension stirring device, if the powder requires stirring with high dispersion force and high shear force, has high viscosity, or is being added in large quantities, the centrifugal plate having high centrifugal blades may be attached to the suction blades.

[0015] This configuration improves the mixing performance when the powder requires high dispersion and shear force stirring, when the viscosity is high, or when a large amount is added.

[0016] In a suspension stirring device, the stirring blade may be supported by a long support extending from the top to the bottom of the tank.

[0017] This configuration allows the drive unit that drives the stirring blades to be located at the top of the tank, thus eliminating the accumulation of heavy powders at the bottom of the tank by placing the stirring blades at the very bottom. [Effects of the Invention]

[0018] The suspension stirring device of the present invention is less prone to clumping, shortens the time required to add powder to the liquid and the time required to disperse and dissolve powder in the liquid, and can handle a wide variety of powders. [Brief explanation of the drawing]

[0019] [Figure 1] This figure shows the configuration of the tank and the liquid flow A and vortex flow B in Embodiment 1 of the present invention. [Figure 2] This figure illustrates the stirring blade in Embodiment 1 of the present invention. [Figure 3] This is a diagram illustrating the slit ring in Embodiment 1 of the present invention. [Figure 4] This is a diagram illustrating the inner wing in Embodiment 1 of the present invention. [Figure 5] This is a diagram illustrating the suction vane in Embodiment 1 of the present invention. [Figure 6] This figure illustrates a centrifugal plate in Embodiment 1 of the present invention. [Figure 7] This is a diagram for explaining the stirring blade in Embodiment 2 of the present invention. [Figure 8] This is a diagram for explaining the inner blade in Embodiment 2 of the present invention. [Figure 9] This is a diagram for explaining the centrifugal plate in Embodiment 2 of the present invention. [Figure 10] This is a diagram for explaining the stirring blade in Embodiment 3 of the present invention.

Mode for Carrying Out the Invention

[0020] (Suspension Stirring Device) The suspension stirring device of Embodiment 1 of the present invention will be described with reference to FIGS. 1 to 6. FIG. 1 is a diagram showing the configuration below the tank in Embodiment 1 of the present invention and liquid flow A and vortex B. FIG. 2 is a diagram for explaining the stirring blade in Embodiment 1 of the present invention. FIG. 3 is a diagram for explaining the slit ring in Embodiment 1 of the present invention. FIG. 4 is a diagram for explaining the inner blade in Embodiment 1 of the present invention. FIG. 5 is a diagram for explaining the suction blade in Embodiment 1 of the present invention. FIG. 6 is a diagram for explaining the centrifugal plate in Embodiment 1 of the present invention.

[0021] As shown in FIG. 1, the suspension stirring device 100 in Embodiment 1 has a stirring blade 2 attached to the upper part of the rotation drive part at the bottom of a stainless steel tank 1 with a curved lower part. Although the upper part of the tank 1 not shown is open in Example 1, it may have a curved and closed structure similar to the lower part of the illustrated tank 1. The stirring blade 2 is made of stainless steel and, as shown in FIGS. 2 and 3, has a cylindrical slit ring 21 provided with a plurality of windows 211 on the entire circumference and inner blades 22 located inside the slit ring and individually rotatable.

[0022] The slit ring 21 is made of stainless steel, has a cylindrical shape, and allows the inner blades 22 to be positioned inside. Also, as shown in the side view of Figure 3(a), a window 211 is provided all around to allow the liquid flow A to pass from the inside to the outside. As shown in the cross-sectional view AA' of Figure 3(b), the lower end of the window 211 is inclined downward from the inside to the outside. In Embodiment 1, the inclination angle of the lower end of the window 21 is 15°, but it may be a larger or smaller angle. The inner blades 22 inside the slit ring 21 are positioned so that the centrifugal plate 222, described later, is facing the window 211 of the slit ring 21. Then, due to the rotation of the centrifugal plate 222 and the inclination provided at the lower end of the window 211, as shown in Figure 1, the liquid flow A flows diagonally downward from the stirring blades 2 and rises along the inner wall of the tank 1 from the bottom inner wall. This allows the powder to be quickly dispersed and dissolved in the liquid.

[0023] As shown in Figure 4, the inner vane 22 has a centrifugal plate 222 screwed to the lower end of the suction vane 221. The suction vane 221 is made of stainless steel and has a structure in which four vane shapes 2211 are provided, which can rotate counterclockwise in a top view to generate a downward vortex B in the tank 1. Also, as shown in the side view of Figure 5(b), two screw portions 2213 are provided at the lower end so that the centrifugal plate can be screwed to it. In addition, a drive shaft hole 2212 is provided that goes through the center, and the drive shaft of a motor provided at the lower end of the tank 1 passes through and is fixed. The suction vane 221 and the centrifugal plate 222 can rotate together as a single unit.

[0024] The centrifugal plate 222 is made of stainless steel and, as shown in the top view of Figure 6(a), has a structure in which six centrifugal vanes 2221 are formed, each having a relatively low height (t1 = approximately 2-3 mm) and an inclination angle that protrudes upward to centrifuge the liquid flow A laterally and slopes downward toward the end. In Example 1, this inclination angle is 15°, the same as the inclination angle of the window 211, but it is not limited to this and can be changed as appropriate. For example, it may be 15° or more, or 15° or less.

[0025] Furthermore, a drive shaft hole 2223 is formed through the center, allowing the motor's drive shaft to pass through. Also, as shown in the side view of Figure 6(b) and the top view of Figure 6(a), four holes 2222 are provided at the lower end so that the suction vane 221 can be screwed in.

[0026] The centrifugal plate 222 is then screwed to the lower end of the suction vane 221 to form the inner vane 22, which is fixed to the drive shaft of a motor located at the lower end of a tank 1 (not shown) and can rotate as a single unit. The inner vane 22 can rotate individually in either a clockwise or counterclockwise direction, but in Embodiment 1, it is rotated counterclockwise when viewed from above.

[0027] Recent research has shown that the height of the centrifugal blades 2221 on the centrifugal plate 222 greatly contributes to the mixing performance, depending on the type and amount of powder. In other words, when the powder requires mixing with high dispersion and shear force, when the viscosity is high, or when a large amount is being added, the centrifugal plate 222 with tall centrifugal blades 2221 greatly contributes to mixing performance. Conversely, in other cases, the centrifugal plate 222 with short centrifugal blades 2221 is found to provide better mixing performance. Therefore, since the centrifugal plate 222 is attached to the lower end of the suction blades 221 with screws, it is designed so that it can be easily replaced with a centrifugal plate 222 with tall centrifugal blades 2221 by loosening the screws and releasing the attachment.

[0028] The slit ring 21 can be rotated independently in either a clockwise or counterclockwise direction by a separate motor (not shown). In Embodiment 1, it is rotated clockwise when viewed from above. However, this is not limited to this configuration and can be modified as appropriate. For example, the slit ring 21 may be rotated clockwise when viewed from above, or the slit ring 21 may be configured to be non-rotatable.

[0029] In Embodiment 1, the drive unit for rotating the stirring blade 2 is attached to the lower end of the tank 1, but this is not necessarily the only option and can be modified as appropriate. For example, the drive unit for rotating the stirring blade 2 may be suspended from above the tank 1 and positioned at the lower end of the tank 1. This makes it possible to place the drive unit for rotating the stirring blade 2 at the top of the tank 1, allowing the stirring blade 2 to be placed closer to the bottom of the tank 1, thus eliminating the accumulation of heavy powders that tend to remain at the bottom of the tank 1.

[0030] (Suspension stirring method) (Example 1) In Example 1, the dispersion and dissolution time of the powder in the liquid was evaluated by the weight of the agglomerated clumps remaining after a predetermined time had elapsed. First, 15 L of pure water was filled into tank 1. Next, 50 g of thickener (carbomer) was added to tank 1 as powder over a period of 10 minutes. The rotation speed of the stirring blade 2 at that time was set to a speed at which the stirring blade 2 was not exposed to the water surface due to the vortex B, with the slit ring 21 rotating at 400 rpm clockwise and the inner blade 22 rotating at 800 rpm counterclockwise so that the vortex B would not obstruct the upward flow of liquid flow A within tank 1.

[0031] Subsequently, the viscosity increased as the powder dispersed and dissolved. Next, the rotation speed was changed as follows to draw in the powder suspended on the surface, and the mixture was stirred for 10 minutes. The rotation speed was changed from 800 rpm clockwise for the slit ring 21 and 1300 rpm counterclockwise for the inner blades 22, to 1000 rpm clockwise for the slit ring 21 and 1800 rpm counterclockwise for the inner blades 22. At this time, the downward vortex B in tank 1 shifted eccentrically from the center and became a strong liquid flow.

[0032] The rotation was stopped, and the dispersed / dissolved material was collected in a mesh while the dispersion / dissolved liquid was discharged. At this point, the weight of the dispersed / dissolved material was 100g. The increase in weight compared to the initial powder input weight of 50g is thought to be due to the powder absorbing water and swelling.

[0033] In Example 1, the slit ring 21 was rotated clockwise and the inner blade 22 was rotated counterclockwise, but this is not necessarily limited to this configuration and can be modified as appropriate. For example, the slit ring 21 may be rotated counterclockwise and the inner blade 22 may be rotated clockwise. In that case, the blade shape 2211 of the suction blade 221 of the inner blade 22 and the centrifugal blade 2221 of the centrifugal plate 222 should be formed in opposite directions. In other words, the slit ring 21 and the inner blade 22 should be rotated in opposite directions.

[0034] (Comparative Example 1) A comparative experiment was conducted with a disperser blade attached to the bottom of Tank 1. First, 15 L of water was filled into Tank 1. Next, 50 g of thickener (Carbopol®) was added to Tank 1 as a powder over a period of 10 minutes. The rotation speed of the disperser blade at that time was set to 500 rpm, which is the rotation speed at which the stirring blade 2 is not exposed to the water surface due to the vortex B.

[0035] Next, the mixture was stirred for 10 minutes to allow any powder suspended on the surface to be absorbed. The rotation speed was 1000 rpm, and since there was no change in viscosity, the rotation speed was not changed.

[0036] The rotation was stopped, and the dispersed / dissolved material was collected using a mesh of the same coarseness as in Example 1, while the dispersed / dissolved material was discharged. The weight of the dispersed / dissolved material at this time was 300g. The increase in weight compared to the initial powder input weight of 50g is thought to be due to the powder absorbing water and swelling, similar to Example 1.

[0037] (Discussion of results for Example 1 and Comparative Example 1) The weight of the remaining dispersed / dissolved material at the end was 100g for Example 1 and 300g for Comparative Example 1. Therefore, it can be said that the powder added to the liquid dispersed and dissolved faster in Example 1 than in Comparative Example 1.

[0038] In Embodiment 1, the weight of the remaining dispersion / dissolved material was used to compare Embodiment 1 and Comparative Example 1, but this was for relative comparison purposes only. Since changing the mesh coarseness changes the weight of the dispersion / dissolved material remaining on the mesh, Embodiment 1 evaluated how much agglomeration remained with a mesh coarseness that did not allow agglomeration of an unacceptable size to pass through.

[0039] (Example 2) In Example 2, the time taken to add the powder to the liquid was evaluated by the weight of the remaining aggregate clumps after a predetermined time had elapsed. First, 15 L of pure water was filled into tank 1. Next, 50 g of thickener (Carbopol®) was added to tank 1 as powder over a shorter period of 5 minutes than in Example 1. At that time, the rotation speed of the stirring blade 2 was the same as in Example 1, with the slit ring 21 rotating at 400 rpm clockwise and the inner blade 22 rotating at 800 rpm counterclockwise.

[0040] Subsequently, the slit ring 21 was stirred at 1000 rpm clockwise and the inner blades 22 at 1500 rpm counterclockwise for 5 minutes, a shorter time than in Example 1. Next, the rotation was stopped, and the dispersion / dissolved material was collected in a mesh and the dispersion / dissolved liquid was discharged. At this point, the weight of the dispersion / dissolved material was 200 g. The increase in weight compared to the initial input weight of 50 g is thought to be due to the powder absorbing water and swelling, which increased its weight.

[0041] In Example 2, the slit ring 21 was rotated clockwise and the inner wing 22 was rotated counterclockwise, but this is not necessarily limited to this configuration and can be modified as appropriate. For example, the slit ring 21 could be rotated counterclockwise. The inner vane 22 may be rotated clockwise by rotating the slit ring 21 in the meter direction. In that case, the orientation of the suction vane 221 of the inner vane 22 and the centrifugal vane 2221 of the centrifugal plate 222 should be reversed. In other words, the slit ring 21 and the inner vane 22 should be rotated in opposite directions.

[0042] (Comparative Example 2) A comparative experiment was conducted with a disperser blade attached to the lower end of Tank 1. Tank 1 was filled with 15 L of pure water. Next, 50 g of a thickening agent (Carbopol®) was added to Tank 1 as a powder over a period of 5 minutes. The rotation speed of the disperser blade at that time was 500 rpm.

[0043] The mixture was then stirred at a rotation speed of 1000 rpm for 5 minutes. Next, the rotation was stopped, and the dispersed / dissolved material was collected using a mesh of the same coarseness as in Example 2, and the dispersed / dissolved material was discharged. At this point, the weight of the dispersed / dissolved material was 260 g. The increase in weight compared to the initial input weight of 50 g is thought to be due to the powder absorbing water and swelling, similar to Example 2.

[0044] (Discussion of results for Example 2 and Comparative Example 2) The weight of the remaining dispersed / dissolved material at the end was 200g for Example 2 and 260g for Comparative Example 2. Therefore, it can be said that the powder was dispersed and dissolved in the liquid more quickly in Example 2 than in Comparative Example 2.

[0045] Thus, in Embodiment 1, a suspension stirring device for stirring powder and liquid comprises: a tank into which the powder and liquid are introduced; a cylindrical slit ring provided at the bottom of the tank and having multiple windows around its entire circumference; and a stirring blade having inner blades located inside the slit ring and capable of rotating individually; the inner blade has a suction blade at the top capable of generating a vortex flow and a centrifugal plate at the bottom capable of generating a centrifugal flow, and the centrifugal plate is replaceable. This suspension stirring device is characterized in that it is less likely to form agglomerates, shortens the time required to introduce powder into the liquid and the time required to disperse and dissolve powder in the liquid, and can handle a wide variety of powders by making the centrifugal plate replaceable. Embodiment 2

[0046] Embodiment 2 of the present invention differs from Embodiment 1 in that the centrifugal plate is configured to be replaceable without loosening screws. Embodiment 2 will be described with reference to Figures 7-9. Figure 7 is a diagram illustrating the stirring blade in Embodiment 2 of the present invention. Figure 8 is a diagram illustrating the inner blade in Embodiment 2 of the present invention. Figure 9 is a diagram illustrating the centrifugal plate in Embodiment 2 of the present invention.

[0047] In Embodiment 2, the stirring blade 2a is removably attached by inserting the pins 223 of the suction blade 221a into the holes 2222 of the centrifugal plate 222a, which is placed on a Teflon base 224. The centrifugal plate 222a is then prevented from rotating by the four pins 223. The four pins 223 can be inserted into the holes 2222 of the suction blade 221a and fixed in place by welding or press-fitting. The Teflon base 224 is made of Teflon (registered trademark) and is fitted tightly to the inner wall of the stirring blade 2a at the bottom. As a result, when the suction blade 221 is removed, the pins 223 are also removed, and the centrifugal plate 222a can be easily removed due to the non-stick effect of the Teflon base. Another centrifugal plate can then be placed on the Teflon base 224 and the pins 223 of the suction blade 221a can be inserted into the holes 2222 of the centrifugal plate 222a for quick replacement.

[0048] The centrifugal blades 2221a of the centrifugal plate 222a are taller than the centrifugal blades 2221 of the centrifugal plate 222 in Embodiment 1, with a height of t2 = 5 to 12 mm. This is effective when the powder being introduced requires high dispersion and high shear force stirring, when the viscosity is high, or when a large amount of powder is being introduced, and significantly improves stirring performance.

[0049] Generally, it is rare to agitate only one type of powder; in most cases, multiple types of powders are agitated. In such cases, if agitation with low shear force is required, if the viscosity is low, or if the input amount is small, the centrifugal plate 222 with low centrifugal blades 2221, as shown in Embodiment 1, is replaced.

[0050] In Embodiment 2, the suction blade 221a is attached in a replaceable manner by inserting the pin 223 of the centrifugal plate 222a into the hole 2222 of the centrifugal plate 222a placed on the Teflon base 224. However, this is not necessarily the only option, and modifications can be made as appropriate. For example, as shown in Embodiment 1, the centrifugal plate 222a may be screwed to the suction blade 221a. In this case, the centrifugal plate 222a can be easily replaced by removing the four screws.

[0051] Furthermore, in Embodiment 2, the centrifugal plate 222a is secured to prevent rotation with four pins 223, but this is not necessarily limited to this configuration and can be modified as appropriate. For example, there may be two or three pins 223.

[0052] Thus, in Embodiment 2, the centrifugal plate is provided in a replaceable form, making it possible to handle a wide variety of powders. Embodiment 3

[0053] Embodiment 3 of the present invention differs from Embodiments 1 and 2 in that the stirring blade is supported by a long support extending from the top to the bottom of the tank. Embodiment 3 will be described with reference to Figure 10. Figure 10 is a diagram illustrating the stirring blade in Embodiment 3 of the present invention, where (a) is a schematic diagram of the suspension stirring device 200 and (b) is a diagram illustrating the stirring blade 3. Although the description of the vortex flow is omitted in Figure 10(a), a vortex flow B similar to that in Embodiment 1 is generated.

[0054] In the suspension agitator 200 of Embodiment 3, the agitator blade 3 is not located at the bottom of the tank 1, but is supported by a long support extending from the top to the bottom of the tank 1. This eliminates the need to have a drive unit for rotating the agitator blade at the bottom of the tank 1, allowing for agitation closer to the bottom. By agitating closer to the bottom, the accumulation of heavier powders at the bottom can be eliminated, improving agitation performance.

[0055] In Embodiment 3, the stirring blade 2a also includes a cylindrical slit ring 21 with multiple windows around its entire circumference, and inner blades 22 located inside the slit ring that can rotate individually. The inner blades 22 have a suction blade 221 at the top that can generate a vortex and a centrifugal plate 222a at the bottom that can generate a centrifugal flow, and the centrifugal plate 222a is detachably mounted.

[0056] Thus, in Embodiment 3, since the stirring blade is supported by a long support extending from the top to the bottom of the tank, the drive unit for driving the stirring blade can be placed at the top of the tank. As a result, the stirring blade can be placed at the very bottom of the tank, eliminating the accumulation of heavy powders that tend to remain at the bottom of the tank. [Industrial applicability]

[0057] The suspension stirring device of the present invention can be widely applied to fields where powders and liquids are stirred. [Explanation of symbols]

[0058] 1: Tank 2: Stirring blade 2a: Stirring blade 3: Stirring blade 21: Slit ring 211: Window 22: Inner blade 100: Suspension stirring device 200: Suspension stirring device 221: Suction blade 222: Centrifugal plate 222a: Centrifugal plate 223: Pin 224: Teflon base 2221: Centrifugal blade 2221a: Centrifugal blade 2212: Hole for drive shaft 2213: Threaded part 2222: Hole 2223: Hole for drive shaft 31: Turbine shaft 32: Support A: Liquid flow B: Vortex flow

Claims

1. A suspension stirring device for stirring powder and liquid, A tank into which the powder and the liquid are introduced, The tank comprises a cylindrical slit ring provided at the bottom of the tank and having multiple windows around its entire circumference, and an agitation blade having inner blades located inside the slit ring and capable of rotating individually, The suspension stirring device is characterized in that the inner blade has a suction blade capable of generating a vortex flow at the top and a centrifugal plate capable of generating a centrifugal flow at the bottom, and the centrifugal plate is attached in a replaceable manner.

2. The suspension stirring device according to claim 1, characterized in that the centrifugal plate is attached to the suction blade by screw fastening.

3. The suspension stirring device according to claim 1, characterized in that the pins of the suction blades are inserted into holes in the centrifugal plate placed on a Teflon base and are attached in a replaceable manner.

4. The suspension stirring apparatus according to claim 1, characterized in that, when the powder requires stirring with high dispersion force and high shear force, has high viscosity, or when a large amount is added, the centrifugal plate having tall centrifugal blades is attached to the suction blades.

5. The suspension stirring device according to claim 1, characterized in that the stirring blade is supported by a long support extending from the top to the bottom of the tank.

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