Liquid level detection float

Abstract

To prevent a liquid level detection float from climbing up or being buried in sludge, etc., accumulated at a bottom part of a liquid storage tank, and to suppress rolling up of the sludge, etc., and the adhesion of the sludge, etc., to the liquid level detection float when unloading the liquid storage tank.SOLUTION: A liquid level detection float has a cylindrical float part 11 that is mounted on a guide part that extends in a vertical direction and is installed in a liquid storage tank so that it can move up and down, where a bottom surface of the float part 11 is provided with eight bottom side vane parts 12 that extend radially in eight directions at 45 degree intervals from a surface extending directly downward from a wall surface of a through hole 13, have a rectangular or square cross-sectional shape, and have lengths of upper and lower sides of the rectangle or square equal to a thickness of the float part 11.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a liquid level detection float used to measure the liquid level in a liquid storage tank that stores a liquid such as oil. [Background technology]

[0002] Conventionally, a liquid level detection float is used to measure the liquid level in a liquid storage tank. For example, as shown in Figure 12, a liquid storage tank 1 that stores a liquid such as oil is equipped with a liquid injection pipe 2, a liquid discharge pipe 3 connected to a pump P and a flow meter M, and a magnetostrictive liquid level gauge 4 that detects the liquid level of the stored liquid and the water level at the bottom of the liquid storage tank 1 and transmits the liquid level data. The magnetostrictive liquid level gauge 4 has a detection unit 5 installed above the liquid storage tank 1, a magnetostrictive wire 6 extending from the detection unit 5 to the bottom of the liquid storage tank 1, an upper liquid level detection float 7 and a lower liquid level detection float 8 which have magnets built in and can slide up and down along a guide unit 10 which has the magnetostrictive wire 6 built in, and a liquid level data transmission unit 9 which transmits liquid level data.

[0003] Furthermore, in the case of the liquid level detection float of such a liquid level gauge, in order to prevent poor conductivity due to scale or rust that occurs inside the tank, or to prevent scale or the like from adhering between the shaft and the float, which can cause the float to move poorly, inventions such as those described in Patent Document 1 (Japanese Utility Model Publication No. 52-10933) and Patent Document 2 (Japanese Patent Publication No. 5-70090) have been proposed. That is, Patent Document 1 describes an invention in which a vane float (7) is connected to a shaft (6) protruding from the bottom of a float (5), and when the vane float (7) rotates due to the water flow in the tank, the float (5) and the conductive material (8) are rotated together, preventing poor conductivity of the conductive material (8) and electrodes (9, 10) (see especially Figure 2, lines 34-36 in the left column of page 1 and lines 32-38 in the right column of the same page). Patent Document 2 describes an invention in which the outer periphery of the float (8) The invention describes an invention in which a large number of blades (9) extend from the surface of the float (8) in a spiral direction symmetrical to the vertical axis (1a), extending in the circumferential direction of the float (8), and the blades (9) receive the force of waves, causing the float (8) to rotate around the vertical axis (1a), thereby preventing dirt such as scale from accumulating between the vertical axis (1a) and the float (8), thereby preventing clogging between the vertical axis (1a) and the float (8) (see especially Figures 1 and 2, and page 2, left column, line 13 to right column, line 3). However, the invention described in Patent Document 1 is intended to prevent poor conductivity within the float chamber, and the invention described in Patent Document 2 is intended to prevent clogging of the vertical shaft (1a) and the float (8), but it does not prevent the float from running up or becoming buried in sludge, scale, rust, iron powder, etc. (hereinafter referred to as "sludge, etc.") that has accumulated at the bottom of the tank, making it impossible to detect the liquid level properly. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Jikko No. 52-10933 [Patent Document 2] Special Publication No. 5-70090 Summary of the Invention [Problem to be solved by the invention]

[0005] The problem that this invention aims to solve is to prevent the liquid level detection float from running over or becoming buried in sludge, etc. that has accumulated at the bottom of the liquid storage tank, and to suppress the sludge, etc. from being stirred up and the sludge, etc. from adhering to the liquid level detection float when unloading. [Means for solving the problem]

[0006] The invention according to claim 1 to solve the above problem is: A liquid level detection float having a cylindrical float portion that is attached to a guide portion that extends in the vertical direction and is installed in a liquid storage tank so as to be movable up and down, The float portion is characterized in that a plurality of bottom blades are provided on the bottom surface of the float portion, extending radially from the central axis side of the float portion.

[0007] The invention according to claim 2 for solving the above problem is the liquid level detection float according to claim 1, The bottom blade portion is characterized in that the distance from the center axis of the float portion increases as it moves downward.

[0008] The inventions according to claims 3 and 4, which are intended to solve the above problems, are the liquid level detection floats according to claims 1 and 2, respectively, The lower portion of the bottom surface side blade portion is characterized in that it becomes thinner as it goes downward.

[0009] The invention according to claim 5 for solving the above problem is a liquid level detection float according to any one of claims 1 to 4, The float portion is characterized in that a plurality of side blade portions are provided on the side surface of the float portion, extending radially from the central axis side of the float portion.

[0010] The invention according to claim 6 for solving the above problem is the liquid level detection float according to claim 5, The bottom blade portion and the side blade portion are provided continuously.

[0011] The invention according to claim 7 for solving the above problem is the liquid level detection float according to claim 5, The bottom surface side wing portion or the side surface side wing portion is characterized in that the cross section taken along a plane perpendicular to the central axis of the float portion is arc-shaped.

[0012] The invention according to claim 8 for solving the above problem is a liquid level detection float according to any one of claims 1 to 4, The float portion is characterized in that a single spiral blade portion is provided on the side surface of the float portion, surrounding the periphery. [Effects of the Invention]

[0013] According to the invention of claim 1, the bottom surface of the float section, which is mounted so as to be able to move up and down relative to a guide section extending in the vertical direction installed on the liquid storage tank, is provided with a plurality of bottom side blade sections extending radially from the central axis side of the float section.Therefore, before the bottom surface of the float section approaches the bottom of the liquid storage tank, the bottom side blade sections rotate in response to the flow of liquid generated in the liquid storage tank, thereby removing sludge and the like that has accumulated at the bottom of the liquid storage tank from below the float section and scattering it around the float section. Therefore, when the bottom surface of the float portion approaches the bottom of the liquid storage tank, there is only a small amount of sludge or the like near the float portion, and the liquid level detection float can be prevented from running over or becoming buried in the sludge or the like that has accumulated at the bottom of the liquid storage tank. Furthermore, when unloading, sludge and the like are less likely to be stirred up near the float portion, which can prevent sludge and the like from adhering to the liquid level detection float.

[0014] According to the invention of claim 2, in addition to the effects of the invention of claim 1, the distance from the central axis of the float portion to the bottom side of the blade portion is greater, so when the bottom side blade portion rotates in response to the flow of liquid generated in the liquid storage tank, sludge, etc. can be removed from below the float portion over a wider area and scattered around the float portion.

[0015] According to the inventions of claims 3 and 4, in addition to the effects of the inventions of claims 1 and 2, respectively, the lower part of the bottom side blade portion becomes thinner as it goes downwards, so when the lower end of the bottom side blade portion hits sludge or the like accumulated at the bottom of the liquid storage tank, it sinks deep and efficiently removes the sludge or the like from below the float portion and scatters it around the float portion.

[0016] According to the invention of claim 5, in addition to the effects of the invention of any of claims 1 to 4, the side of the float section is provided with multiple side blade sections extending radially from the central axis side of the float section, and the bottom blade section and side blade section can receive the flow of liquid that occurs in the liquid storage tank, so the float section can rotate even if the flow is weak.

[0017] According to the invention of claim 6, in addition to the effect of the invention of claim 5, since the bottom surface side blade portion and the side surface side blade portion are provided continuously, molding of the float portion is easy.

[0018] According to the invention of claim 7, in addition to the effect of the invention of claim 5, the bottom side blade portion or the side side blade portion has an arc-shaped cross section cut by a plane perpendicular to the central axis of the float portion, so that it can efficiently receive the liquid flow that occurs in the liquid storage tank, and can rotate the float portion even with a weak flow.

[0019] According to the invention of claim 8, in addition to the effects of the invention of any of claims 1 to 4, a single spiral blade portion is provided surrounding the side of the float portion, so that even if the liquid flow generated in the liquid storage tank is turbulent, especially if an upward or downward flow occurs, the liquid flow can be reliably captured and the float portion can be rotated. [Brief explanation of the drawings]

[0020] [Figure 1] 1 is a diagram illustrating the structure of a liquid level detection float according to a first embodiment. [Figure 2]6 is a diagram illustrating the structure of a liquid level detection float according to a second embodiment. [Figure 3] 10 is a diagram illustrating the structure of a liquid level detection float according to a third embodiment. [Figure 4] 10 is a diagram illustrating the structure of a liquid level detection float according to a fourth embodiment. [Figure 5] 10 is a diagram illustrating the structure of a liquid level detection float according to a fifth embodiment. [Figure 6] 10 is a diagram illustrating the structure of a liquid level detection float according to a fourth modified example. [Figure 7] 10 is a diagram illustrating the structure of a liquid level detection float according to a fifth modified example of the first embodiment. [Figure 8] 10 is a diagram illustrating the structure of a liquid level detection float according to a fifth modified example of the second embodiment. [Figure 9] 10 is a diagram illustrating the structure of a liquid level detection float according to a fifth modified example of the third embodiment. [Figure 10] 13 is a diagram illustrating the structure of a liquid level detection float according to a sixth modified example. [Figure 11] 13 is a diagram illustrating the structure of a liquid level detection float according to Modification 7. [Figure 12] 1 is a diagram showing a conventional liquid storage tank equipped with a magnetostrictive liquid level gauge and the like. DETAILED DESCRIPTION OF THE INVENTION

[0021] The liquid level detection float of the present invention rotates the float in response to the liquid flow generated in the liquid storage tank via the bottom blades and side blades before the bottom of the float approaches the bottom of the liquid storage tank. The liquid flow generated by this rotation and the contact of the lower end of the bottom blade with sludge, etc., expels sludge, etc., that has accumulated at the bottom of the liquid storage tank from below the float and scatters it around the float. Therefore, in the case of the magnetostrictive liquid level gauge 4 installed in the liquid storage tank 1 shown in Figure 12, it is applied to the lower liquid level detection float 8 which can slide up and down along the magnetostrictive wire 6 and detects the water level of the water accumulated at the bottom of the liquid storage tank 1. Hereinafter, embodiments of the present invention will be described with reference to examples. The explanation of the liquid level detection float according to each example is based on the premise that it is used as the lower liquid level detection float 8. However, the present invention is not limited to magnetostrictive level gauges, and can be applied to any level gauge that has a float portion that is attached to a guide portion so as to be movable up and down. [Example]

[0022] 1(A) to 1(E) are respectively a plan view, a front view, a bottom view, a perspective view, and a cross-sectional view taken along line AA in FIG. 1(A) of the liquid-level detection float according to the first embodiment. The liquid level detection float of Example 1 has a cylindrical float part 11 that is attached to a guide part 10 (see Figure 12) that has a magnetostrictive wire 6 built in so that it can move up and down, and eight bottom side blade parts 12 that extend radially from the central axis side of the float part 11 on the bottom surface of the float part 11. The float part 11 has an overall specific gravity set to be smaller than that of water and larger than that of liquids such as oil, and the through-hole 13 provided along the central axis is inserted into the guide part 10, so that the float part 11 can freely move up and down according to the water surface level. As shown in Figures 1(C) to (E), the bottom-side blade portion 12 extends radially in eight directions at 45-degree intervals from a plane extending directly downward from the wall surface of the through hole 13, and its cross-sectional shape is rectangular or square, with the lengths of the upper and lower sides of the rectangle or square being equal to the thickness of the float portion 11.

[0023] The liquid level detection float of Example 1 is configured as described above, so when a liquid such as oil is discharged from the liquid storage tank 1 through the liquid discharge pipe 3 or when a liquid such as oil is injected into the liquid storage tank 1 through the liquid injection pipe 2, and a flow of liquid occurs within the liquid storage tank 1, the bottom side blade portion 12 receives the flow and the float portion 11 rotates. Then, sludge and the like accumulated at the bottom of the liquid storage tank 1 is scattered around the float part 11, so that the sludge and the like can be removed from below the float part 11. In other words, since only a small amount of sludge or the like is always maintained below the float portion 11, when the bottom side blade portion 12 approaches the bottom of the liquid storage tank 1, it is possible to prevent its lower end from riding up on or becoming buried in sludge or the like, which would make it impossible to detect the normal liquid level (the water surface level when applied to the lower liquid level detection float 8 in Figure 12). [Example]

[0024] 2(A) to 2(E) are a plan view, a front view, a bottom view, a perspective view, and a cross-sectional view along line BB in FIG. 2(A), respectively, of the liquid-level detection float according to the second embodiment. The liquid level detection float according to the second embodiment differs from the first embodiment only in that the eight bottom surface blades 14 provided on the bottom surface of the float portion 11 are shaped to widen downward. Therefore, the description of the configuration other than the bottom blade portion 14 will be omitted, and the same reference numerals as in FIG. 1 will be used in the description of the second embodiment. 2(C) to 2(E), the bottom-side blades 14 of Example 2 extend radially in eight directions at 45-degree intervals from a plane extending directly downward from the wall surface of the through-hole 13, with the distance from the central axis of the float section 11 increasing the further downward. The cross-sectional shape is trapezoidal, with the length of the upper side of the trapezoid equal to the thickness of the float section 11 and the length of the lower side of the trapezoid longer than the thickness of the float section 11.

[0025] Due to the above-mentioned configuration, the liquid level detection float of Example 2 has a longer lower side of the bottom side blade portion 14, and is more susceptible to the effect of the flow when a liquid flow occurs in the liquid storage tank 1 than the bottom side blade portion 12 of Example 1.As a result, the bottom side blade portion 14 rotates efficiently and can remove sludge and the like from below the float portion 11 over a wider area and scatter it around the float portion 11. [Example]

[0026] 3(A) to 3(E) are respectively a plan view, a front view, a bottom view, a perspective view, and a cross-sectional view taken along line CC in FIG. 3(A) of the liquid-level detection float according to the third embodiment. The liquid level detection float according to the third embodiment differs from the first embodiment only in that bottom-side blades 15 and side-side blades 16 are provided on the bottom and side of the float portion 11, respectively. Therefore, the description of the configuration other than the bottom blade portion 15 and the side blade portion 16 will be omitted, and the same reference numerals as in FIG. 1 will be used in the description of the third embodiment. As shown in Figures 3(C) to (E), the bottom side blade portion 15 of Example 3 extends radially in eight directions at 45-degree intervals from a plane extending directly downward from the wall surface of the through hole 13, and its cross-sectional shape is rectangular or square, with the lengths of the upper and lower sides of the rectangle or square being longer than the thickness of the float portion 11. In addition, the side wing portion 16 of Example 3 extends radially in eight directions from the side of the float portion 11 around the central axis at 45-degree intervals, and its cross-sectional shape is rectangular, with the lengths of the upper and lower sides of the rectangle being equal to the length of the bottom wing portion 15 minus the thickness of the float portion 11. Although the bottom blade portion 15 and the side blade portion 16 have been described separately here, they are provided continuously.

[0027] The liquid level detection float of Example 3 is configured as described above, so when a liquid flow occurs in the liquid storage tank 1, the bottom side blade portion 15 and the side side blade portion 16 are affected by the flow, and are therefore more strongly affected by the flow than the bottom side blade portion 14 of Example 2.Furthermore, since the length of the lower side of the bottom side blade portion 15 is equal to or greater than that of the bottom side blade portion 14 of Example 2, the ability to remove sludge and the like from below the float portion 11 and scatter it around the float portion 11 is greater than that of the liquid level detection float of Example 2. [Example]

[0028] 4(A) to 4(D) are a plan view, a front view, a bottom view, and a perspective view, respectively, of the liquid-level detecting float according to the fourth embodiment. The liquid level detection float according to the fourth embodiment differs from the third embodiment only in that the eight side blades 17 provided on the side surfaces of the float portion 11 are spiral. Therefore, the description of the configuration other than the side blade portion 17 will be omitted, and the same reference numerals as those in FIGS. 1 and 3 will be used in the description of the fourth embodiment. As shown in Figures 4(B) and (D), the side wing portion 17 of Example 4 extends radially in eight directions from the side of the float portion 11 around the central axis at 45-degree intervals and is twisted spirally, with its lower end surface coinciding with the surface of the bottom wing portion 15 protruding from the side of the float portion 11, and its upper end surface being offset by approximately 60 degrees from the lower end surface.

[0029] The liquid level detection float of Example 4 is configured as described above, so that even if an upward or downward flow occurs within the liquid storage tank 1, the spirally twisted side blade portion 17 can capture the liquid flow and rotate the float portion 11. [Example]

[0030] 5(A) to 5(D) are a plan view, a front view, a bottom view, and a perspective view, respectively, of a liquid-level detecting float according to a fifth embodiment. The liquid level detection float of Example 5 differs from Example 3 in that the eight bottom side blade portions 18 provided on the bottom surface of the float portion 11 are shaped to widen downwards, and the side side blade portion provided on the side of the float portion 11 is a single spiral blade portion 19. Therefore, explanation of the configuration other than the bottom blade portion 18 and the spiral blade portion 19 will be omitted, and the same reference numerals as in FIGS. 1 and 3 will be used in the explanation of the fifth embodiment. 5(C) and (D), the bottom-side blades 18 of Example 5 extend radially in eight directions at 45-degree intervals from a plane extending directly downward from the wall surface of the through-hole 13, with the distance from the central axis of the float section 11 increasing the further downward. The cross-sectional shape is trapezoidal, with the length of the upper side of the trapezoid equal to the thickness of the float section 11 and the length of the lower side of the trapezoid longer than the thickness of the float section 11. 5(B) and (D), the spiral blade portion 19 is composed of a single spiral plate that surrounds the side surface of the float portion 11, and makes three turns from the bottom end of the side surface of the float portion 11, then ascends to the top end of the same side surface. The number of turns can be determined as appropriate.

[0031] Like the liquid level detection float of Example 2, the liquid level detection float of Example 5 has the above-mentioned configuration, in which the lower side of the bottom side blade portion 18 is long, and when a liquid flow occurs in the liquid storage tank 1, it is more susceptible to the effect of the flow than the bottom side blade portion 12 of Example 1.As a result, the bottom side blade portion 18 rotates efficiently and can remove sludge and the like from below the float portion 11 over a wider area and scatter it around the float portion 11. Furthermore, since the float portion 11 has a side blade portion 19 consisting of a single spiral plate around its side, even if an upward or downward flow occurs within the liquid storage tank 1, the side blade portion 19 can capture the liquid flow and rotate the float portion 11.

[0032] Modifications of the liquid level detection floats according to the first to fifth embodiments will be listed below. (Variation 1) The float part 11 in Examples 1 to 5 was cylindrical with a through hole 13, but it is not limited to a cylindrical shape, and as long as it has a through hole 13 that can be inserted into the guide part 10, the cross section cut along a plane perpendicular to the central axis of the float part 11 may have any shape. However, to prevent tilting due to buoyancy, it is better for the cross section shape to be bilaterally symmetrical or rotationally symmetrical. (Variant 2) The liquid level detection floats according to Examples 1 to 5 have eight bottom-side blade portions 12, 14, 15, and 18, and the liquid level detection floats according to Examples 3 and 4 also have eight side-side blade portions 16 and 17, all of which extend radially in eight directions at 45-degree intervals from the central axis of the float portion 11, but the eight bottom-side blade portions and side-side blade portions may be multiple pieces that extend radially from the central axis of the float portion 11 around the central axis at equal intervals. (Modification 3) In the first to fifth embodiments, the lower end surfaces of the bottom blade portions 12, 14, 15, and 18 are all flat surfaces extending radially from the center axis of the float portion, but they may also be curved surfaces. In particular, when the bottom of the liquid storage tank 1 on which the liquid level detection float is installed is a downwardly convex curved surface, it is advantageous to make the curved surface parallel to the line with the smallest radius of curvature among the lines extending radially along the bottom from the intersection of the central axis of the float portion 11 and the bottom of the liquid storage tank 1, because even if the float portion 11 approaches the bottom, parts other than the innermost of the bottom side blade portions 12, 14, 15, and 18 will not come into contact with the bottom. (Modification 4) In Examples 1 to 5, the thickness of the bottom surface side blades 12, 14, 15, and 18 was uniform, but the thickness of the lower part of the bottom surface side blades may be made thinner. For example, Figures 6(A) to (C) are respectively a front view, a bottom view, and an oblique view of a liquid level detection float according to variant 4 of Example 1, and the bottom side blade portion 20 has a tapered portion 21 at the bottom that becomes thinner as it goes downward. When the lower end of the bottom-side blade portion 20 of the liquid level detection float according to Modification 4 hits sludge or the like accumulated at the bottom of the liquid storage tank 1, it sinks deep into the sludge and efficiently removes the sludge from below the float portion 11 and scatters it around the float portion 11. In addition, because the tapered portion 21 easily sinks into sludge or the like accumulated at the bottom, it also has the effect of making it less likely that an abnormal liquid level will be detected.

[0033] (Modification 5) The side surfaces of the bottom blades 12, 14, 15, and 18 in Examples 1 to 5 and the side blades 16 in Example 3 are all flat surfaces extending radially from the central axis of the float 11, but they may also be curved. In the case of the liquid level detection float according to Example 3, which has the bottom blades 15 and the side blades 16, either one of the two side surfaces may be a curved surface. For example, Figures 7(A) to (C) are respectively a front view, a bottom view, and an oblique view of a liquid level detection float according to variant 5 of Example 1, and the bottom side blade portion 22 has an arc-shaped cross section cut along a plane perpendicular to the central axis of the float portion 11. 8(A) to 8(C) are respectively a front view, a bottom view, and an oblique view of a liquid level detection float according to variant 5 of embodiment 2, and the bottom side blade portion 23 has an arc-shaped cross section cut along a plane perpendicular to the central axis of the float portion 11. Furthermore, Figures 9(A) to (C) are respectively a front view, a bottom view, and an oblique view of a liquid level detection float relating to variant example 5 of embodiment 3, and the bottom side blade portion 24 and the side side blade portion 25 have an arc-shaped cross section cut along a plane perpendicular to the central axis of the float portion 11. Furthermore, the bottom side blade portions 22, 23, 24 or the side side blade portion 25 of the liquid level detection float of variant example 5 have an arc-shaped cross section cut on a plane perpendicular to the central axis of the float portion 11, so they can efficiently receive the liquid flow that occurs in the liquid storage tank 1, and the float portion 11 can rotate even if the liquid flow is weak.

[0034] (Variant 6) In Examples 1 to 5, the bottom side blade portions 12, 14, 15, and 18 all extend radially from a plane extending directly downward from the wall surface of the through hole 13, and their cross-sectional shapes are rectangular or square for the bottom side blade portions 12 and 15, and trapezoidal for the bottom side blade portions 14 and 18, but the cross-sectional shape may be a shape other than rectangular, square, or trapezoid. For example, FIG. 10(A) is a cross-sectional view of a liquid-level detection float according to a sixth modification of the first embodiment, and FIG. 10(B) is a cross-sectional view of a liquid-level detection float according to a sixth modification of the second embodiment. The cross-sectional shape of the bottom-side blade portions 26, 27 of these liquid level detection floats is triangular, and the lower surfaces of the bottom-side blade portions 26, 27 are inclined surfaces that slope diagonally downward and outward from the lower end of the wall surface of the through hole 13. The inclined surface may be a curved surface or may be a surface made up of a plurality of flat surfaces. Furthermore, the cross-sectional shape may be a trapezoid whose bottom side is shorter than its top side. Furthermore, even if the cross section of the bottom side blade portion has the shape described above, the effect obtained is not significantly different from the effect obtained by the liquid level detection float of Examples 1 to 5. If the shape is as shown in Figure 10(A) or (B), when the lower ends of the bottom side blade portions 26, 27 hit sludge or the like accumulated at the bottom of the liquid storage tank 1, they are likely to sink in, making it less likely that an abnormal liquid level will be detected.

[0035] (Modification 7) In the third embodiment, the bottom blade portion 15 and the side blade portion 16 are provided continuously, but they do not have to be continuous. 11(A) to 11(C) are respectively a front view, a bottom view, and a perspective view of a liquid-level detection float according to Modification 7 of the bottom blade portion 15 and the side blade portion 16 in Example 3, in which the bottom blade portion 28 and the side blade portion 29 are not connected but are offset by 22.5 degrees. Even with such a configuration, the effects obtained are not significantly different from those obtained by the liquid-level detection float according to Example 3. (Variant 8) The side wing portion 16 in Example 3 and the side wing portion 17 in Example 4 were provided continuously from the lower end to the upper end of the float portion 11, but either may be provided continuously from the lower end or lower part to the upper end, or may be provided continuously from the lower part to the upper end or upper part, or may be provided intermittently from the lower end or lower part to the upper end or upper part. [Explanation of symbols]

[0036] 1 Liquid storage tank 2 Liquid injection pipe 3 Liquid discharge pipe 4 Magnetostrictive liquid level gauge 5 Detector 6 Magnetostrictive wire 7 Upper liquid level detection float 8 Lower liquid level detection float 9 Liquid level data transmission unit 10 Guide unit 11 float portion 12 bottom side blade portion 13 through hole 14, 15 Bottom blades 16, 17 Side blades 18 Bottom blades 19 Spiral blade portion 20 Bottom blade portion 21 Tapered portion 22, 23, 24 Bottom blades 25 Side blades 26, 27, 28 Bottom blades 29 Side blades P Pump M Flow meter

Claims

1. A liquid level detection float having a cylindrical float portion that is vertically movable relative to a guide portion that is installed in a liquid storage tank and extends in a vertical direction, A plurality of bottom blades are provided on the bottom surface of the float portion so as to extend radially from the central axis side of the float portion. A liquid level detection float characterized by:

2. The bottom surface side blade portion has a greater distance from the center axis of the float portion toward the lower side.

2. The liquid level sensing float according to claim 1.

3. The lower portion of the bottom surface side blade portion is thinner toward the lower side.

2. The liquid level sensing float according to claim 1.

4. The lower portion of the bottom surface side blade portion is thinner toward the lower side.

3. The liquid level sensing float according to claim 2.

5. A plurality of side blades are provided on the side of the float portion so as to extend radially from the central axis of the float portion.

5. The liquid level detection float according to claim 1,

6. The bottom blade portion and the side blade portion are provided continuously.

6. The liquid level sensing float according to claim 5.

7. The bottom surface side wing portion or the side surface side wing portion has an arc-shaped cross section cut along a plane perpendicular to the central axis of the float portion.

6. The liquid level sensing float according to claim 5.

8. A spiral blade is provided around the side surface of the float.

5. The liquid level detection float according to claim 1,

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