Liquid level detection sensor float

Abstract

To provide a liquid level detection sensor float with which it is possible to accommodate weights 3, 3' different in weight downward of a float unit 1, and with which in no case will sludge accumulate near a weight accommodation unit 4.SOLUTION: Provided is a liquid level detection sensor float, in which a locking unit 2 capable of moving in an inner direction is provided below a float unit 1, and a toric weight 3 is inserted from below the float unit 1, whereby making it possible to accommodate the weight 3 in a weight accommodation unit 4 and adjust the weight of the whole of the float unit 1. The liquid level detection sensor float includes a spacer 12 whose cross-sectional shape cut at the horizontal plane is the same as that of the toric weight 3. The combined height of the weight 3 and the spacer 12 is equal to the height of the weight accommodation unit 4. The outer diameter of the spacer 12 is the same as or smaller than the outer diameter at the lower end of a cylindrical float body 6. The top face of the spacer 12 closely adheres to the underside of the float body 6.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a liquid level detection sensor float used for measuring the liquid level in a liquid storage tank for storing liquids such as oil.

Background Art

[0002] Conventionally, a liquid level detection sensor float has been used to measure the liquid level in a liquid storage tank. For example, as described in Patent Document 1 (Japanese Patent Application Laid-Open No. 2005-351767), the applicant has developed a magnetostrictive liquid level gauge having a first magnet-equipped float (1) for detecting the oil level in a liquid storage tank and a second magnet-equipped float (2) for detecting the water level, and having a water detection function for detecting whether water is accumulated in the liquid storage tank based on the fluctuation of the second magnet-equipped float (2) (see particularly paragraph 0016 and FIG. 1). In addition, Patent Document 2 (Japanese Patent Application Laid-Open No. 2001-4434) describes that in a tank liquid level measuring device, a ballast (35) is provided for the water detection float (7) so that the bulk density of the entire float is slightly larger than the density of the liquid stored in the tank (1) and smaller than that of water (see particularly paragraph 0020 and FIG. 6). Patent Document 3 (Japanese Patent Application Laid-Open No. 2007-107986) describes that in a float type tank liquid level detection device, the weight of the lower float (31) of the water detection float group (30) is adjusted by a ballast (33) (see particularly paragraph 0020 and FIG. 1).

[0003] However, Patent Document 1 does not describe the specific configurations of the first magnet-equipped float (1) and the second magnet-equipped float (2). Although it is described that the overall specific gravity of the first magnet-equipped float (1) is smaller than that of oil and the overall specific gravity of the second magnet-equipped float (2) is smaller than that of water and larger than that of oil (see paragraph 0016), it is unclear how to adjust the overall specific gravity of each float (1) and (2). Although Patent Documents 2 and 3 describe adjusting the bulk density and weight of the float using ballast, they do not describe specific configurations such as the ballast (35) for adjusting the bulk density of the float and the ballast (33) for adjusting the weight of the lower float (31).

[0004] Therefore, the applicant developed a liquid level detection sensor float that can adjust the weight of the entire float part 1 by providing a locking part 2 below the float part 1 that can move up and down with respect to a guide part extending in the vertical direction installed in the liquid storage tank, making the locking part 2 movable in the inner direction of the float part 1, and inserting an annular weight 3 from below the float part 1 to accommodate weights 3 of different weights in the weight accommodation part 4. FIGS. 5(A) and (B) are respectively a front view of the developed liquid level detection sensor float and a cross-sectional view taken along a plane including the center line. As shown in FIG. 5, the float part 1 is composed of a cylindrical body 5 and a cylindrical float body 6 that can be detachably fixed around the cylindrical body 5. The locking part 2 is provided at the lower end of the cylindrical body 5, and a weight accommodation part 4 is formed between the lower surface of the float body 6 and the upper surface of the locking part 2. In addition, since the cylindrical body 5 is provided with a plurality of slits 7 extending upward from the lower end, due to the flexibility of the material (such as hard plastic or metal such as stainless steel) constituting the cylindrical body 5, the plurality of locking parts 2 can move in the inner direction of the cylindrical body 5. Note that the cylindrical body 5 is provided with a locking part 8 for the float body at the upper end and a plurality of upper-side slits 9 extending downward from the upper end. The locking part 8 for the float body can also move in the inner direction of the cylindrical body 5 in the same manner as the locking part 2. Therefore, the small-diameter part 10 of the float body 6 can be inserted from the upper end of the cylindrical body 5. And when the lower end of the small-diameter part 10 hits the upper end of the large-diameter part 11 of the cylindrical body 5, the upper end of the small-diameter part 10 is located below the locking part 8 for the float body. So, the plurality of locking parts 8 for the float body return to their original positions at that position, and the float body 6 is fixed around the cylindrical body 5.

Prior Art Documents

Patent Documents

[0005] Patent Document 1 Japanese Unexamined Patent Application Publication No. 2005-351767 (Patent No. 4149963) Patent Document 2 Japanese Unexamined Patent Application Publication No. 2001-4434 (Patent No. 3307610) Patent Document 3 Japanese Unexamined Patent Application Publication No. 2007-107986 (Patent No. 4097091) Summary of the Invention Problems to be Solved by the Invention

[0006] However, when the developed liquid level detection sensor float is used, sludge accumulates in the gap between the lower surface of the float body 6 and the upper surface of the weight 3, and the float portion 1 fails to float in the liquid for which the liquid level is to be measured. The problem to be solved by the present invention is to provide a liquid level detection sensor float that can accommodate weights of different weights below the float portion 1 and prevent sludge from accumulating near the weight accommodation portion 4 so as to avoid such a situation. Means for Solving the Problems

[0007] The invention according to claim 1 for solving the above problems is a liquid level detection sensor float that is vertically movably attached to a guide portion extending in the vertical direction installed in a liquid storage tank, a float portion composed of a cylindrical body that is vertically movable with respect to the guide portion and a cylindrical float body fixed around the cylindrical body, a locking portion provided below the cylindrical body, a weight accommodation portion between the float body and the locking portion, including a weight and a spacer accommodated in the weight accommodation portion, the combined height of the weight and the spacer being equal to the height of the weight accommodation portion, Of the weight and the spacer, the uppermost one has its upper peripheral edge in close contact with the lower surface of the float body, Of the weight and the spacer, the lower one has its upper peripheral edge in close contact with the lower surface of the weight or the spacer directly above it and the spacer consists of two semi-annular bodies, and the two semi-annular bodies can be fixed by joining their end faces together which is characterized by the above.

Advantages of the Invention

[0010] According to the invention according to claim 1, the combined height of the weight and the spacer accommodated in the weight accommodation part is equal to the height of the weight accommodation part. Of the weight and the spacer, the uppermost one has its upper peripheral edge in close contact with the lower surface of the float body, and of the weight and the spacer, the lower one has its upper peripheral edge in close contact with the lower surface of the weight or the spacer directly above it. Therefore, weights of different weights can be accommodated in the weight accommodation part below the float part, and a liquid level detection sensor float in which sludge does not accumulate near the weight accommodation part can be provided. Also, since the spacer consists of two semi-annular bodies and the two semi-annular bodies can be fixed by joining their end faces together, the spacer can be easily attached to the weight accommodating portion of the liquid level detection sensor float that does not already have a spacer installed.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Modes for Carrying Out the Invention

[0014] Hereinafter, embodiments of the present invention will be described by way of examples.

Example

[0015] FIG. 1(A) is a front view of the liquid level detection sensor float according to Embodiment 1, and FIGS. 1(B) and (C) are cross-sectional views of the same liquid level detection sensor float. As can be seen by comparing FIGS. 1(A) and (B) with FIGS. 5(A) and (B), the liquid level detection sensor float according to Embodiment 1 is different from the liquid level detection sensor float developed by the applicant beforehand only in that it has the spacer 12. Therefore, the description of each component other than the spacer 12 and the spacer 12' and the weight 3' in FIG. 1(C) will be omitted, and the same drawing numbers as in FIG. 5 will be used for the drawing numbers of each component.

[0016] As shown in FIGS. 1(A) and (B), the liquid level detection sensor float according to Embodiment 1 has an annular spacer 12 having the same shape as the weight 3 having an annular cross-sectional shape cut in a horizontal plane with respect to the liquid level detection sensor float (see FIGS. 5(A) and (B)) developed by the applicant beforehand, and the combined height of the weight 3 and the spacer 12 is equal to the height of the weight accommodating portion 4. And the outer diameter of the spacer 12 is the same as or smaller than the outer diameter at the lower end of the cylindrical float body 6, and the upper surface of the spacer 12 is in close contact with the lower surface of the float body 6. That is, by inserting the annular spacer 12 from below the float portion 1, and then inserting the weight 3, and accommodating the spacer 12 and the weight 3 stacked in the weight accommodating portion 4, there is no flat portion on the upper surface in the vicinity of the weight accommodating portion 4 (the lower part of the float body 6, the outer peripheral portions of the spacer 12 and the weight 3). Therefore, it is possible to obtain a liquid level detection sensor float in which sludge is unlikely to accumulate in the vicinity of the weight accommodating portion 4.

[0017] FIG. 1(C) is a cross-sectional view of the liquid level detection sensor float when the weight 3 and the spacer 12 shown in FIGS. 1(A) and (B) are replaced with a weight 3' that is thicker and heavier than the weight 3 and a spacer 12' that is thinner than the spacer 12, respectively, to increase the overall specific gravity of the liquid level detection sensor float and make it sink in a liquid with a larger specific gravity. The weights 3' and spacers 12' in Fig. 1(C) also have the same cross-sectional shape when cut in the horizontal plane as the weights 3 and spacers 12. The combined height of the weight 3' and the spacer 12' is equal to the height of the weight receiving portion 4. The outer diameter of the spacer 12' is the same as or smaller than the outer diameter at the lower end of the cylindrical float body 6, and the upper surface of the spacer 12' is in close contact with the lower surface of the float body 6. Note that by adjusting the combined weight of the weight and the spacer, the overall specific gravity of the liquid level detection sensor float can be adjusted. However, if the specific gravity of the spacers 12, 12' is made equal to the specific gravity of the liquid in which the liquid level detection sensor float floats, it is better because the weights 3, 3' previously used in the liquid level detection sensor float developed by the applicant can be used as they are.

Example

[0018] Fig. 2 is a plan view (upper side) and a front view (lower side) for explaining the structure of the assembled spacer 13 used in the liquid level detection sensor float according to Example 2. The liquid level detection sensor float according to Example 2 differs from the liquid level detection sensor float according to Example 1 only in that the annular spacer 12 (see Figs. 1(A) and (B)) used in Example 1 is replaced with the assembled spacer 13 shown in Fig. 2(A). And the other configurations of the liquid level detection sensor float according to Example 2 are the same as those of Example 1. As shown in Fig. 2(A), the assembled spacer 13 is composed of a first semi-annular body 14 and a second semi-annular body 15, and its outer diameter, inner diameter, and thickness are equal to the outer diameter, inner diameter, and thickness of the spacer 12. Therefore, the front view and cross-sectional view when the assembled spacer 13 is attached to the float portion 1 are almost the same as Figs. 1(A) and (B). Therefore, the description of the configurations other than the assembled spacer 13 will be omitted, and the same reference numerals as in Fig. 1 will be used in the description of Example 2.

[0019] As shown in the plan views of FIGS. 2(B) and 2(C), inside the two end faces of the first semi-annular body 14, a notch portion 16 having a flat portion orthogonal to both end faces and a flat portion parallel to both end faces is provided, and an engaging concave portion 17 is provided at the corner of the notch portion 16. Further, near the inside of the two end faces of the second semi-annular body 15, a prismatic protruding portion 18 extending perpendicularly from both end faces is provided, and an outward engaging convex portion 19 is provided at the tip of the protruding portion 18. Since the first semi-annular body 14 and the second semi-annular body 15 have such a structure, when the protruding portion 18 of the second semi-annular body 15 is inserted into the notch portion 16 of the first semi-annular body 14 and the engaging convex portion 19 is fitted into the engaging concave portion 17, the two end faces of the two semi-annular bodies 14 and 15 are fixed in a joined state, and the two are integrated to form the assembled spacer 13. Therefore, even when the liquid level detection sensor float shown in FIG. 5 is already installed, the assembled spacer 13 can be easily attached to the float portion 1 by simply inserting the first semi-annular body 14 and the second semi-annular body 15 from both sides into the gap between the lower surface of the float body 6 and the upper surface of the weight 3 with almost no movement of the float portion 1.

Example

[0020] FIG. 3 is a cross-sectional view of the liquid level detection sensor float according to Example 3. The liquid level detection sensor float according to Example 3 is different from the liquid level detection sensor float according to Example 1 only in that the annular and solid spacer 12 (see FIGS. 1(A) and 1(B)) used in Example 1 is made into an L-shaped spacer 20 having an L-shaped cross-sectional shape of the annular portion cut by a plane including the center line shown in FIG. 3(A) or a U-shaped spacer 21 having a U-shaped cross-sectional shape shown in FIG. 3(B). And, the other configurations of the liquid level detection sensor float according to Example 3 are the same as those of Example 1. As shown in Fig. 3(A), the outer diameter, inner diameter, and thickness of the L-shaped spacer 20 are equal to the outer diameter, inner diameter, and thickness of the spacer 12. As shown in Fig. 3(B), since the outer diameter and thickness of the U-shaped spacer 21 are equal to the outer diameter and thickness of the spacer 12, the front view when the weight 3 and the L-shaped spacer 20 or the weight 3 and the U-shaped spacer 21 are accommodated in the weight accommodation part 4 is almost the same as Fig. 1(A). Therefore, the description of the configurations other than the L-shaped spacer 20 and the U-shaped spacer 21 will be omitted, and the same numbers as those in Fig. 1 will be used in the description of Fig. 3 and Example 3 as well.

[0021] As shown in the cross-sectional view of Fig. 3(A), the upper surface of the L-shaped spacer 20 is in close contact with the lower surface of the float body 6, and the lower surface is in close contact with the upper peripheral edge of the weight 3. Note that the L-shaped spacer 20 may be turned upside down. In such a case, the upper surface of the L-shaped spacer 20 will be in close contact with the lower peripheral edge of the float body 6, and the lower surface will be in close contact with the upper surface of the weight 3. Also, although the inner diameter of the L-shaped spacer 20 is equal to the inner diameter of the weight 3, it may be larger than the inner diameter of the weight 3 as long as it can be stably accommodated in the weight accommodation part 4, and it may be smaller than the inner diameter of the weight 3 as long as it is not less than the outer diameter of the large diameter part 11 of the cylindrical body 5.

[0022] As shown in the cross-sectional view of Fig. 3(B), the upper surface of the U-shaped spacer 21 is in close contact with the lower surface of the float body 6, and the lower surface is in close contact with the upper surface of the weight 3. Note that the inner diameter of the U-shaped spacer 21 is larger than the inner diameter of the weight 3, but it may be equal to the inner diameter of the weight 3, and it may be smaller than the inner diameter of the weight 3 as long as it is not less than the outer diameter of the large diameter part 11 of the cylindrical body 5. Also, although the inner diameter of the upper side and the inner diameter of the lower side of the U-shaped spacer 21 are equal, the inner diameter of the upper side and the inner diameter of the lower side may be different as long as the U-shaped spacer 21 can be stably installed in the gap between the lower surface of the float body 6 and the upper surface of the weight 3.

Example

[0023] Figs. 4(A) and (B) are respectively a front view and a cross-sectional view of the liquid level detection sensor float according to Example 4. The liquid level detection sensor float according to Example 4 is different from the liquid level detection sensor float according to Example 1 only in that a cylindrical and flexible sleeve 22 shown in Fig. 4 is used instead of the annular spacer 12 used in Example 1. And the other configurations of the liquid level detection sensor float according to Example 4 are the same as those of Example 1. Therefore, the description of the configurations other than the sleeve 22 is omitted, and the same numbers as those in Fig. 1 are also used in the description of Fig. 4 and Example 4.

[0024] As shown in Figs. 4(A) and (B), the inner diameter of the sleeve 22 is substantially the same as the outer diameters of the lower part of the float body 6 and the weight 3, and the height of the sleeve 22 is larger than the height of the weight accommodating part 4. Further, protrusions 23 are provided on the entire circumference or a plurality of locations on the inner surface side of the sleeve 22. When using a cylindrical and flexible sleeve 22 with such a shape and size, after accommodating a weight 3 of an appropriate weight in the float part 1, it can cover the space between the periphery of the lower part of the float body 6 and the periphery of the weight 3. Therefore, the periphery of the weight accommodating part 4 becomes a smooth surface with almost no unevenness. Thus, similar to Examples 1 to 3, a liquid level detection sensor float can be obtained in which there is no risk of sludge accumulating near the weight accommodating part 4. Also, the protrusions 23 provided on the inner surface side are caught by the upper peripheral edge of the weight 3, so that the sleeve 22 is less likely to fall off from the float part 1.

[0025] List deformation examples regarding the liquid level detection sensor floats according to Examples 1 to 4. (Modification Example 1) In Examples 1 to 4, the float part 1 is composed of a cylindrical body 5 and a float body 6 that can be detachably fixed around the cylindrical body 5. However, the float body 6 does not have to be detachable. In that case, the locking part 8 for the float body and the upper end side slit 9 do not have to be provided. (Modification Example 2) In Examples 1 to 4, the float portion 1 was composed of a cylindrical body 5 and a cylindrical float body 6 that could be detachably fixed around the cylindrical body 5. However, instead of the cylindrical body 5 and the cylindrical float body 6, a cylindrical body with a polygonal or elliptical cross-sectional shape cut in a horizontal plane and a cylindrical float body fixed around the cylindrical body may be used. However, when using a cylindrical body with a polygonal cross-sectional shape, in order to make the locking portion 2 and the locking portion 8 for the float body movable in the inner direction of the cylindrical body, it is necessary to provide slits 7 and upper end side slits 9 at all ridge portions. (Modification Example 3) In Examples 1 to 4, the locking portion 2 was provided at the lower end of the cylindrical body 5. However, since the annular weight 3 only needs to be accommodated below the float portion 1, the locking portion 2 may be provided below the cylindrical body 5.

[0026] (Modification Example 4) In Examples 1 to 4, the weight 3 was made annular and inserted from below the cylindrical body 5. In Modification Example 4, the cross-sectional shape of the weight was made polygonal or elliptical annular and inserted from below the cylindrical body. However, the weight may also be composed of two semi-annular bodies similar to the assembled spacer 13 of Example 2, or two semi-annular bodies similar to the spacer of Modification Example 4. In such a case, since it is not necessary to make the locking portion 2 movable in the inner direction of the cylindrical body, the slit 7 does not need to be provided. (Modification Example 5) In Examples 1 to 4, the weight 3, the spacer 12, the assembled spacer 13, the L-shaped spacer 20, and the U-shaped spacer 21 were made annular. However, when using a cylindrical body with a polygonal or elliptical cross-sectional shape instead of the cylindrical body 5 as in Modification Example 2, the weight 3, the spacer 12, the assembled spacer 13, the L-shaped spacer 20, and the U-shaped spacer 21 also need to have an annular cross-sectional shape that is polygonal or elliptical. Also, in that case, in Example 2, the assembled spacer is composed of two semi-annular bodies. (Modification Example 6) In Examples 1 to 3, the outer diameters of the weight 3, the spacer 12, the assembled spacer 13, the L-shaped spacer 20, and the U-shaped spacer 21 were the same. However, if the outer diameter at the lower end of the float body 6 is the same as or smaller than the outer diameter of the weight 3, the outer diameters of the spacer 12, the assembled spacer 13, the L-shaped spacer 20, and the U-shaped spacer 21 may be larger than the outer diameter of the weight 3. (Modification Example 7) In Examples 1 to 3 and Modification Examples 1 to 6, the weight 3 was disposed below the various spacers. However, the weight 3 may be disposed above the various spacers. Also, in such a case where the outer diameters of the weight 3 and the various spacers are made different as in Modification Example 6, it is necessary to make the outer diameters of the various spacers smaller than the outer diameter of the weight 3. That is, when making the outer diameters of the weight 3 and the various spacers different, the one on the upper side of the weight 3 and the various spacers should have a larger outer diameter than the one on the lower side, and the outer peripheral edge of the weight 3 or the various spacers on the uppermost side should be in close contact with the lower surface of the float body 6, and the outer peripheral edge of the weight 3 or the various spacers on the lower side should be in close contact with the lower surface of the weight 3 or the various spacers directly above it.

[0027] (Modification Example 8) In Examples 1 to 3 and Modification Examples 1 to 7, the weight 3 and the various spacers were separate bodies and were respectively accommodated in the weight accommodating portion 4 separately. However, the weight 3 and the various spacers may be integrated and accommodated in the weight accommodating portion 4. (Modification Example 9) In Example 4, the protrusion 23 was provided on the entire circumference or a plurality of locations on the inner surface side of the sleeve 22. However, since the sleeve 22 is made of a flexible material, if the inner diameter of the upper part of the sleeve 22 is made smaller than the outer diameter of the lower part of the float body 6, or the inner diameter of the lower part of the sleeve 22 is made smaller than the outer diameter of the weight 3, it is possible to make it difficult for the float portion 1 to fall off, so the protrusion 23 may not be provided.

Explanation of Reference Numerals

[0028] 1 Float portion 2 Locking portion 3, 3' Weight 4 Weight accommodating portion 5 Cylindrical body 6 Float body 7 Slit 8 Locking portion for float body 9 Upper end side slit 10 Small-diameter part 11 Large-diameter part 12, 12' Spacer 13 Assembled spacer 14 First semi-annular body 15 Second semi-annular body 16 Notch part 17 Engaging concave part 18 Protruding part 19 Engaging convex part 20 L-shaped spacer 21 C-shaped spacer 22 Sleeve 23 Protrusion

Claims

【Claim 1】 A liquid level detection sensor float that is vertically movably attached to a vertically extending guide portion installed in a liquid storage tank, a float portion including a cylindrical body that is vertically movable with respect to the guide portion and a cylindrical float body fixed around the cylindrical body, a locking portion provided below the cylindrical body, a weight accommodation portion between the float body and the locking portion, including a weight and a spacer accommodated in the weight accommodation portion, the combined height of the weight and the spacer is equal to the height of the weight accommodation portion, the uppermost one of the weight and the spacer has its upper peripheral edge in close contact with the lower surface of the float body, the lower one of the weight and the spacer has its upper peripheral edge in close contact with the lower surface of the weight or the spacer directly above it, the spacer consists of two semi-annular bodies, the two semi-annular bodies can be fixed by joining their both end faces together characterized by a liquid level detection sensor float.

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