JPH0963436A - Float switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a float switch in which the generation of an oxide film can be prevented. SOLUTION: The horizontal length of the support part 9b of a shaft 9 is made long, compared with the upper part 9a, and a substantially ring-like movable contact member 16 made of conductive material in which the inside diameter of a hole is large, compared with the horizontal length dimension of the upper part 9, and small, compared with the horizontal length dimension of the support part 9b, and the outer edge part has a size making contact with a pair of projection parts 14 is inserted to the upper part 9a of the shaft 9. The movable contact member 16 becomes vertically movable and rotatable relative to the upper part 9a, and it is easily rotated by the rocking of the shaft 9 and apt to be slipped, compared with the initial placed state. Therefore, when the movable contact member 16 makes contact with the projection parts 14, the contact part is never limited to a specified part, so that the generation of an oxide or the formation of a dent in the movable contact member 16 or the projection parts 14, or the generation of the oxide in the dent can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a float switch used for a liquid storage container such as an oil tank of a two-stroke motorcycle.

[0002]

2. Description of the Related Art An example of a conventional float switch is a float switch 1 for an oil tank shown in FIGS. 9 and 10, a switch body 4 made of a resin material is provided on an oil (liquid) 3 stored in an oil tank (container) 2 and attached to a fixing member such as a lid (not shown).

The switch body 4 is integrally provided with a pair of metal fixed contact plates 5. An alarm device such as a power source and a lamp (not shown) is connected in series to the base end sides of the pair of fixed contact plates 5, and the alarm device is activated by connecting the pair of fixed contact plates 5. ing.

The front ends of the pair of fixed contact plates 5 are opposed to each other and extend downward, and the ends are fitted and fixed to a holding member 6 made of an insulating material having a substantially circular shape. As shown in FIG. 11, a rectangular window 7 extending vertically is formed in the pair of fixed contact plates 5 by punching.

A float 8 is floated on the liquid surface of the oil 3. A shaft 9 having a rectangular pillar shape made of an insulating material is attached to the float 8, and is inserted between the pair of fixed contact plates 5 through a hole (hereinafter, referred to as a shaft hole) 10 formed in the holding member 6. Has been done.

A hole (hereinafter, referred to as a movable contact hole) 11 that opens to the pair of windows 7 is formed in the shaft 9. A shaft 12 that crosses the movable contact hole 11 is provided on the wall of the shaft 9 that forms the movable contact hole 11. A wire member 13 for a movable contact is attached to the shaft 12, and both ends thereof are inserted into the pair of windows 7, respectively.

The float switch 1 configured as described above
Then, when the liquid level of the oil 3 is lowered and the float 8 is lowered, the wire member 13 is also lowered accordingly. Then, when the wire member 13 comes into contact with the lower window frame portion 7a forming the pair of windows 7, the switch is turned on and the alarm is activated to notify that the remaining amount of the oil 3 has decreased.

[0008]

In the float switch 1 described above, the contact portion between the wire member 13 and the lower window frame portion 7a is limited to a specific location. For this reason, oxide is generated in the contact portion, pitting corrosion occurs in the contact portion to cause depressions in the wire member 13 and the pair of fixed contact plates 5, and oxide is generated or attached to the generated depressions. It could happen that the energization was interrupted.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a float switch capable of suppressing the generation of an oxide film.

[0010]

In order to achieve the above-mentioned object, the present invention provides a pair of fixed contact members made of a conductive material that face each other on a liquid stored in a container and extend vertically. A pair of fixed contact members is provided with projections extending in the fixed contact member on the mating side and spaced apart from each other in the horizontal direction, and a shaft made of an insulating material is attached to a float floating in the liquid. Vertically movably inserted into the space between the parts, and the length of the intermediate part of the shaft in the horizontal direction is set longer than the upper part of the intermediate part,
Forming a substantially ring shape, the inner diameter of the hole is larger than the horizontal length of the upper portion of the shaft and smaller than the horizontal length of the intermediate portion of the shaft,
Further, a movable contact member made of a conductive material having a size such that an outer edge portion contacts the pair of protrusions is inserted into an upper portion of the shaft. In this case, irregularities may be formed on the lower side of the movable contact member.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A float switch according to an embodiment of the present invention will be described below with reference to FIGS.
It should be noted that description and illustration of members and parts equivalent to those shown in FIGS. 9 to 11 will be omitted as appropriate.

In a pair of fixed contact plates (fixed contact members) 5 made of a conductive material such as metal, instead of the window 7 of the conventional technique,
As shown in FIG. 2 and FIG. 3, protrusions 14 are formed by cutting and raising so that the tip ends extend to the fixed contact plate 5 on the other side. The pair of protrusions 14 are opposed to each other with the shaft 9 in between, and a gap 15 is formed between them.

The shaft 9 attached to the float 8 is
It is inserted in a space 15 between the pair of protrusions 14 so as to be vertically movable. The lower portion including the middle portion of the shaft 9 constitutes a rectangular support portion 9b that horizontally protrudes with respect to the square column-shaped upper portion 9a, and the horizontal length of the support portion 9b is the shaft 9 Is longer than the horizontal length of the upper portion 9a.

The upper portion 9a of the shaft 9 is made of a ring-shaped conductive material having a circular cross section shown in FIG. 5 in a state where the shaft 9 is inserted into the shaft hole 10 of the holding member 6 as shown in FIG. The movable contact member 16 is inserted. In the movable contact member 16, as shown in FIG. 4, the inner diameter of the hole 16a is larger than the maximum horizontal length m of the upper portion 9a of the shaft 9 and the horizontal length of the support portion 9b is large. The size is smaller than the dimension n, and the outer edge portion is set to have a size in contact with the pair of protrusions 14. Since the inner diameter of the hole 16a is larger than the maximum horizontal length m of the upper portion 9a of the shaft 9 as described above, the ring-shaped movable contact member 16 is attached to the upper portion 9a of the shaft 9. On the other hand, it can be vertically moved and rotated, and can be easily rotated by swinging the shaft 9 or the like. Further, since the inner diameter of the hole 16a is smaller than the horizontal length n of the supporting portion 9b, the ring-shaped movable contact member 16 is normally placed on the supporting portion 9b by its own weight. It will be. In the figure, 17 is a rod-shaped stopper attached to the upper portion 9 a of the shaft 9.
When is lowered, it is locked to the pair of protrusions 14 via the movable contact member 16 to prevent the shaft 9 from falling off.

In the float switch 1 constructed as described above, the movable contact member 16 is normally placed on the support portion 9b by its own weight. Then, when the liquid level of the oil 3 is lowered and the float 8 is lowered, the support portion 9 is accompanied with this.
b, by extension, the movable contact member 16 also descends. When the descent further proceeds, the movable contact member 16 comes into contact with the pair of protrusions 14 and the switch is turned on, whereby the alarm device operates and notifies that the remaining amount of the oil 3 has decreased.

The movable contact member 16 is vertically movable and rotatable with respect to the upper portion 9a of the shaft 9, and when the support portion 9b descends, the movable contact member 16 is easier than when it was initially placed. Shift occurs. Therefore, the movable contact member 16
When contacting the pair of protrusions 14, the contact portion is not limited to a specific portion, so that an oxide is generated in the movable contact member 16 or the pair of protrusions 14, a dent is formed, or an oxide is formed in the dent. It is possible to prevent the generation of electricity, and thus to ensure good electricity supply.

In the above embodiment, the fixed contact plate 5 is formed with the pair of protrusions 14 by cutting and raising, so that metal scraps and the like are not generated. In the above-mentioned conventional technique, since the window 7 is formed by punching in the fixed contact plate 5 made of metal, metal scrap is generated, but according to the embodiment of the present invention, the generation of metal scrap is not caused. It is not necessary to remove metal scraps, and productivity can be improved. Further, in the above embodiment, the case where the fixed contact member is a plate-shaped member (fixed contact plate 5) has been described as an example, but the fixed contact member is not limited to this and may be a rod-shaped member.

Further, in the above embodiment, the case where the movable contact member 16 has a ring shape with a circular cross section is taken as an example.
Instead of this, it may have a tubular shape as shown in FIG. In this case, as shown in FIG.
6b may be formed. If the floating switch 1 is configured using the movable contact member 16 shown in FIG. 7, even if the oxide is attached to the pair of protrusions 14, when the movable contact member 16 contacts the pair of protrusions 14. , Unevenness 1
6b comes into contact with the oxide and scrapes it off, so that good electrical conductivity can be obtained.

In this embodiment, as shown in FIG. 8, the length of the diagonal line T of the vertical cross section of the movable contact member 16 is set larger than the distance between the pair of metal plates 5, 5. .
With this configuration, even if the movable contact member 16 is vibrated or tilted for some reason and becomes slanted, it is possible to prevent a short circuit.

In the above embodiment, the case where the shaft 9 has a quadrangular prism shape is taken as an example, but it may have a cylindrical shape, or a polygonal pillar shape such as a triangular pillar shape or a pentagonal pillar shape.

In the above embodiment, the case where the liquid is oil and the container is the oil tank has been described as an example, but the present invention is not limited to this, and a liquid such as water may be used.

[0022]

According to the present invention, since the inner diameter of the hole of the ring-shaped movable contact member is larger than the horizontal length of the upper portion of the shaft, the movable contact member is attached to the upper portion of the shaft. On the other hand, it can be moved up and down and rotated, and is easily rotated due to rocking of the shaft and the like, and is likely to be displaced as compared with the initially placed state. Therefore, when the movable contact member comes into contact with the pair of protrusions, the contact portion is not limited to a specific portion, and oxides are generated in the movable contact member or the pair of protrusions, or a dent is formed or a dent is formed. It is possible to prevent the formation of oxides, and to ensure good electric conduction.

[Brief description of drawings]

FIG. 1 is a front view showing a float switch according to an embodiment of the present invention.

FIG. 2 is a side view showing the float switch.

FIG. 3 is an exploded perspective view showing the float switch.

FIG. 4 is a partially cutaway plan view showing the float switch.

FIG. 5 is a perspective view showing a movable contact member of the float switch.

FIG. 6 is a perspective view showing another movable contact member.

FIG. 7 is a perspective view showing still another movable contact member.

FIG. 8 is a schematic diagram showing a dimensional relationship between a tubular movable contact member and a pair of fixed contact members.

FIG. 9 is a front view showing a conventional float switch.

FIG. 10 is a side view showing the float switch.

FIG. 11 is an exploded perspective view showing the float switch.

[Explanation of symbols]

 1 Float Switch 2 Oil Tank 3 Oil 5 Fixed Contact Plate 8 Float 9 Shaft 9a Upper Part 9b Support Part 14 Projection Part 15 Gap 16 Movable Contact Member 16a Hole

Claims (2)

[Claims] 1. A pair of fixed contact members made of a conductive material, which face each other on a liquid stored in a container and extend in the up-and-down direction, are provided, and each of the pair of fixed contact members has a fixed contact member on the other side. The respective extending projections are formed separately in the horizontal direction, and the shaft made of an insulating material attached to the float floating in the liquid is vertically movably inserted into the space between the pair of projections, The length in the horizontal direction is set longer than that of the upper portion of the intermediate portion,
Forming a substantially ring shape, the inner diameter of the hole is larger than the horizontal length of the upper portion of the shaft and smaller than the horizontal length of the intermediate portion of the shaft,
Furthermore, a float switch, wherein a movable contact member made of a conductive material having a size such that an outer edge portion contacts the pair of protrusions is inserted into an upper portion of the shaft. 2. The float switch according to claim 1, wherein irregularities are formed on the lower side of the movable contact member.