JP7082741B2 - Liquid level detector - Google Patents

Description

The present invention relates to a liquid level detection device.

Conventionally, a liquid level detecting device for detecting the height of the liquid level of a liquid stored in a container such as a fuel tank has been known.
For example, the liquid level detection device disclosed in Patent Document 1 rotatably supports a holder (rotating member) that rotates with the movement of the float following a change in the height of the liquid level, and the holder. A terminal having a frame (support member), an electrode portion having a plurality of electrodes provided on the holder, and a contact portion provided on the frame and slidingly contacting one of the electrodes of the electrode portion according to the rotation position of the holder. And. In this liquid level detecting device, the liquid level is electrically detected from the change in the resistance value depending on the position where the electrode of the electrode portion and the contact portion of the terminal are in sliding contact.

Japanese Unexamined Patent Publication No. 2018-80951

In the liquid level detection device disclosed in Patent Document 1, the holder rotates with a clearance between the holder and the frame while pressing the electrode portion against the terminal of the frame. For this reason, the holder may come into contact with the frame due to looseness of the rotating shaft portion, which hinders smooth rotation of the holder and may reduce detection accuracy and reliability.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a liquid level detection device that ensures smooth rotation and does not cause deterioration of detection accuracy and reliability.

In order to achieve the above object, the liquid level detection device according to the first aspect of the present invention is
A rotating member that rotates around the axis of rotation as the height of the liquid level changes,
A support member that rotatably supports the rotating member,
A plurality of electrodes provided on the rotating member and
It is provided with a contact member provided on the support member and the electrodes that are in sliding contact are switched among the plurality of electrodes according to the rotation position of the rotating member.
The support member includes a first flat surface portion having a uniform height on a surface facing the rotating member according to the rotation position of the rotating member.
It is characterized by that.

Further, the liquid level detecting device according to the second aspect of the present invention is
A rotating member that rotates around the axis of rotation as the height of the liquid level changes,
A support member that rotatably supports the rotating member,
A plurality of electrodes provided on the rotating member and
It is provided with a contact member provided on the support member and the electrodes that are in sliding contact are switched among the plurality of electrodes according to the rotation position of the rotating member.
The support member includes a second flat surface portion that narrows the facing gap on the facing surface facing the rotating member according to the rotation position of the rotating member.
It is characterized by that.

According to the present invention, it is possible to provide a liquid level detection device that ensures smooth rotation and does not cause deterioration of detection accuracy or reliability.

According to an embodiment of the liquid level detection device of the present invention, (a) is a schematic perspective view, and (b) is a schematic perspective view of a mounting base. According to an embodiment of the present invention, (a) is a schematic perspective view in a state where the arm holder is inverted, and (b) is an explanatory view of a circuit board. It is the schematic perspective view of only the frame part which concerns on one Embodiment of this invention. It is the schematic perspective view of only the frame part which concerns on another Embodiment of this invention. It is a schematic side view explaining the facing gap which concerns on another Embodiment of this invention.

An embodiment of the liquid level detection device according to the present invention will be described with reference to the drawings.
As shown in FIGS. 1 and 2, the liquid level detecting device 1 includes a float 10, a float arm 20, an arm holder (rotating member) 30, a frame (supporting member) 40, and a circuit board 50. Be prepared. The circuit board 50 includes a plurality of electrodes 51 and 52, and the frame 40 includes a contact member 46 that slides while contacting the electrodes 51 and 52.

The float 10 is formed in a hollow shape by a synthetic resin so as to float on the liquid surface of a liquid in a fuel tank (not shown). The float 10 is displaced according to the height of the liquid level of the liquid.

The float arm 20 is formed of metal in a rod shape, and the arm holder 30 is rotated according to the position of the float 10.
The float arm 20 includes an L-shaped arm main body 21 extending between the float 10 and the arm holder 30, a first bent portion 22 located at one end of the arm main body 21 and to which the float 10 is mounted, and an arm main body. A second bent portion 23 located at the other end of the portion 21 and attached to the arm holder 30 is provided. The first bent portion 22 and the second bent portion 23 are each formed so as to bend at a right angle (direction orthogonal to the paper surface) with respect to the plane of the L-shaped arm main body portion 21. The second bent portion 23 constitutes a rotation shaft O that rotatably supports the frame 40. Further, the shape of the arm main body 21 is not limited to the L shape depending on the mounting position of the liquid level detection device 1 to the fuel tank or the like, and the shape can be appropriately changed and displaced according to the change in the height of the liquid level. Will be done.

The arm holder 30 is an example of a rotating member, and as shown in FIGS. 1 to 3, the arm holder 30 rotates with respect to the frame 40 about the rotation axis O together with the float arm 20 while holding the float arm 20. The arm holder 30 is formed of a synthetic resin into a substantially (baseball) home base shape in which a substantially quadrangle and a substantially triangle are integrally combined.
The arm holder 30 is composed of a substantially triangular rotation support portion 31 and a substantially square main body portion 32, and the main body portion 32 includes an inner substrate holding portion 33 and an outer arm holding portion 34. To prepare for.

As shown in FIGS. 1 and 2 (a), the rotation support portion 31 is formed in a U-shape so as to cover the apex portion of the triangle from the outside at a distance from the outer surface of the substantially triangle. A bearing hole 31a is formed on the facing surface (inner side surface). A frame 40, which will be described later, is arranged between the facing U-shaped portions of the rotation support portion 31, and the second bent portion 23 of the float arm 20 is inserted into the bearing hole 31a from the outside to rotate. The tip of the second bent portion 23 is located inside the support portion 31.
As a result, the frame 40 is arranged between the seat surface portions 31b of the U-shaped shaft of the rotation support portion 31 to prevent the second bent portion 23 of the arm holder 30 and the float arm 20 from coming off.

As shown in FIG. 2A, a substrate holding portion 33 is formed inside the rectangular main body portion 32, and a recess is formed inside the arm holder 30. As shown in FIG. 2B, the circuit board 50 has a rectangular plate shape, and the periphery of the circuit board 50 is mounted and held in a recess. The board holding portion 33 is integrally formed with a locking portion 33a for locking the two peripheral sides of the circuit board 50, and holds the circuit board 50 by bringing the remaining two sides into contact with the concave side wall surface.

As shown in FIG. 1, the arm holding portion 34 on the outer side of the main body portion 32 has a grip portion 34a arranged from the apex of the triangle of the rotation support portion 31 toward the bottom along the central portion of the main body portion 32. The grip portion 34a is formed integrally with the main body portion 32 and grips the arm main body portion 21. The grip portion 34a is provided with a cylindrical portion corresponding to the outer shape of the arm main body portion 21, and is formed by opening the side of the cylindrical portion. As a result, the float arm 20 is gripped by the arm holder 30 by elastically deforming it from the opening of the grip portion 34a and pushing the arm main body portion 21 into the cylindrical portion, and the arm holder is integrated with the movement of the float arm 20. 30 rotates.

As shown in FIG. 2, the main body portion 32 is integrally formed with a holder-side stopper portion 35 that regulates the rotation range of the arm holder 30, and the arm holder 30 is brought into contact with the stopper portion 43 of the frame 40 to be described later. Regulate the rotation range of. The holder-side stopper portion 35 utilizes two right-angled side wall portions at the corners formed so as to protrude inward from the substrate holding portion 33 (frame 40 side, upper in FIG. 2), and is a substantially square main body portion 32. One right-angled portion (the portion closer to the float 10) far from the rotation support portion 31 (the portion in the direction orthogonal to the float arm 20 in FIG. 2A) and the other right-angled portion (FIG. 2 (a). The end surface 35b (see FIG. 1) provided on the portion in the direction parallel to the float arm in a) is used as the stopper surface.

As shown in FIG. 3, the frame 40 includes a substantially square frame main body portion 41, and the frame main body portion 41 is formed with accommodating recesses 45 on both sides of a partition portion for partitioning the front and back (inside and outside). A housing recess 45a is formed on the front side (the side facing the arm holder 30) of the frame main body 41. A pair of contact members 46 are accommodated in the accommodating recess 45. Further, in the frame 40, when the arm holder 30 is attached, the contact member 46 in the accommodating recess 45 of the frame 40 and the substrate holding portion 33 of the arm holder 30 rotatably attached to the frame 40 face each other. Arranged to do. As a result, the contact member 46 and the plurality of electrodes 51 and 52 of the circuit board 50 are in a state where they can be in sliding contact with each other.
The detailed shape of the accommodating recess 45a for smoothly rotating the arm holder 30 with respect to the frame 40 will be described later.

The bearing portion 42 is for rotatably supporting the arm holder 30, and is formed at a position protruding to the side (right side in FIG. 3) of the frame main body portion 41. The bearing portion 42 has a through hole and is mounted between the U-shaped rotation support portions 31 of the arm holder 30, and is a second bent portion of the float arm 20 from the outside of the rotation support portion 31 of the arm holder 30. 23 is inserted as the rotation axis O. As a result, the arm holder 30 is rotatably supported by the frame 40 about the rotation axis O.

As shown in FIG. 2A, the pair of contact members 46 are directed toward the plurality of electrodes 51 and 52 (see FIG. 2B) of the circuit board 50 held by the substrate holding portion 33 of the arm holder 30. It is formed so as to protrude and is arranged in parallel. Each contact member 46 is formed in a substantially comb shape by a conductor such as nickel silver so as to be elastically deformable. The pair of contact members 46 are, for example, insert-molded into a synthetic resin constituting the frame 40.
Each contact member 46 has a contact 46a that contacts any of the plurality of electrodes 51 and 52 of the circuit board 50 and a terminal portion 46b to which the wiring cord 47 is connected, depending on the rotation position of the arm holder 30. Be prepared. The contact 46a is located on one end side (inside of the liquid level detection device 1) of each contact member 46 close to the arm holder 30 side, and protrudes toward the arm holder 30 side. The terminal portion 46b is located on the other end side (outside of the liquid level detection device 1) of each contact member 46 far from the arm holder 30. When the arm holder 30 rotates with respect to the frame 40, the electrode 51 with which the contact 46a is in contact is switched among one of the plurality of electrodes 51 on the circuit board 50.
The terminal portion 46b is connected to an external device (not shown) via the wiring cord 47.
As a result, the liquid level detection device 1 outputs an output signal corresponding to the position of the float 10 to the external device via the wiring cord 47 connected to the terminal portion 46b. The external device receives this output signal and recognizes the position of the float 10, that is, the height of the liquid level.

As shown in FIGS. 1 and 3, the stopper portion 43 on the frame 40 side regulates the rotation range of the arm holder 30 by contacting the end face 35a and the end face 35b of the holder side stopper portion 35 of the arm holder 30, respectively. do.
The stopper portions 43 are arranged on the side wall portions of the frame main body portion 41 at two locations separated by a predetermined angle about the rotation axis O. Each stopper portion 43 has a stopper surface 43a with which the end surfaces 35a and 35b on both sides of the holder side stopper portion 35 come into contact with each other.

The stopper portion 43 includes a detachment prevention portion 43b that prevents the arm holder 30 from detaching when the allowable rotation range (rotation angle) regulated by the stopper surfaces 43a on both sides is exceeded. The detachment prevention portion 43b is formed so as to project from the outer end portion of each stopper surface 43a, and the rotation is restricted by hitting the holder side stopper portion 35 that rotates beyond the rotation range, and the arm holder 30 gets over it. Prevent withdrawal.

The mounting portion 44 is formed in a parallel plate shape in which both sides of the frame 40 project outward to form a guided portion. The mounting portion 44 is provided along a mounting target (not shown), for example, a guide portion 71 in which the openings of the grooves 71a opened on two sides of the mounting plate 70 fixed to the fuel pump module in the fuel tank are opposed to each other. It is for mounting and mounting (see FIG. 1 (b)).
The mounting portion 44 includes a locking portion 44a for locking the mounting plate 70 with the guide portion 71. The locking portions 44a are formed on both sides of the frame 40 so as to protrude above the surface of the mounting portion 44, and are parallel to a notch perpendicular to the outer surface of the frame 40 from the tip of the locking portion 44a and the outer surface connected to the notch. The elastic portion 44b is formed by an L-shaped notch with a notch to the base end. As a result, the locking portion 44a protruding upward from the surface of the mounting portion 44 can be pushed back downward (back side) by elastically deforming the elastic portion 44b.

The mounting plate 70 is fixed to a fuel pump module or the like in the fuel tank to be mounted. The mounting plate 70 includes a guide portion 71, and as shown in FIG. 1 (b), the mounting plate 70 is configured such that the openings of the two grooves 71a having an L-shaped cross-sectional shape and laterally open openings face each other. .. The guide portion 71 is formed to have a slightly wider width so that the distance between the two grooves 71a corresponds to the width of the mounting portion 44 which is the guided portion. As a result, the frame 40 can be fixed to the mounting plate 70 by mounting the mounting portion 44 of the frame 40 between the two grooves 71a of the guide portion 71.
The guide portion 71 is formed with an engaging portion 71b that engages the locking portion 44a of the mounting portion 44 by cutting out in the middle of the groove 71a. As a result, the frame 40 is mounted on the guide portion 71, and the locking portion 44a of the frame 40 is positioned on the engaging portion 71b, so that the locking portion 44a protrudes upward and is engaged with the engaging portion 71b. The frame 40 can be fixed at a predetermined position of the mounting plate 70 fixed to the mounting target (not shown).

As shown in FIG. 2B, the circuit board 50 is made of a ceramic substrate and is formed in the shape of a rectangular plate. The circuit board 50 is fixed to the rear surface of the arm holder 30 by the locking portion 33a of the board holding portion 33 of the arm holder 30 described above. A plurality of electrodes 51 and 52 are formed on the circuit board 50, and a resistor 53 is electrically connected to the plurality of electrodes 51 and 52. As a result, the electrode 51 with which the contact 46a of the contact member 46 contacts is switched among the plurality of electrodes 51 according to the rotation position of the arm holder 30 with respect to the frame 40.

In this liquid level detection device 1, in order to smoothly rotate the arm holder 30 with respect to the frame 40, the frame (support member) 40 has the arm holder 30 according to the rotation position of the arm holder (rotating member) 30. A first flat surface portion 60 having a uniform height is provided on the facing surface facing the surface. That is, in the first flat surface portion 60, as shown in FIGS. 1 and 3, the surface of the accommodating recess 45a on the front side of the frame 40 (the surface facing the arm holder 30) is continuous with the flat surface of the frame main body portion 41. It is a flat surface, and as shown by a two-dot chain line in FIG. 3, the two corners on the terminal portion 46b side of the accommodating recess 45a so far are formed as a large flat surface portion 60a in which the two corners are filled in an arc shape. As a result, in the range of the locus in which the arm holder 30 rotates around the rotation axis O (the range inside the circle whose radius R is the farthest point of the arm holder 30 from the center of the rotation axis O), the arm holder 30 Can smoothly rotate on the frame 40 without being caught in the recess of the accommodating recess 45a due to the backlash of the rotation shaft O or the like. Therefore, the movement of the float 10 that is displaced according to the change in the height of the liquid surface can be smoothly transmitted to the arm holder 30, and smooth rotation is ensured to improve the detection accuracy and the reliability of deformation resistance. be able to.
Although the flat surface portion 60a is formed at the two corner portions, it may be formed on only one of the arm holders 30 that is far from the rotation axis O (only on the left side in the figure), and is symmetrical to both. By providing the above, it is possible to make the generation of distortion due to resin molding uniform and to minimize the deformation. Further, the shape of the flat surface portion 60a is not limited to the case where the corner portion is filled in an arc shape, and the arm holder 30 has another shape or the arm holder 30 so as to form a linear flat surface portion without filling the entire corner portion. You may not be depressed.

Next, other embodiments of the present invention will be described with reference to FIGS. 4 and 5.
In this liquid level detection device 1A, in order to smoothly rotate the arm holder 30 with respect to the frame 40, the frame (support member) 40 has the arm holder 30 according to the rotation position of the arm holder (rotating member) 30. A second flat surface portion 61 for narrowing the facing gap is provided on the facing surface facing the surface. That is, as shown in FIG. 4, the second flat surface portion 61 is formed in a rib shape having a flat surface on the front surface (the surface facing the arm holder 30) of the frame 40. The second flat surface portion 61 is formed so as to narrow the conventional gap d1 between the frame 40 and the arm holder 30 to the facing gap d. As shown by cross-hatching in FIG. 4, the second flat surface portion 61 has a range of a locus in which the arm holder 30 rotates about the rotation axis O (the point farthest from the center of the rotation axis O of the arm holder 30). Is an inner range of a circle having a radius R), and is arranged so as to narrow the facing gap d between the frame 40 and the arm holder 30. As a result, even if the arm holder 30 comes into contact with the frame 40 due to looseness of the rotating shaft O or the like, the facing gap d is narrowed so that the arm holder 30 slides on the second flat surface portion 61 without being caught and the frame. It can smoothly rotate on the second flat surface portion 61 of the 40.
Therefore, the movement of the float 10 that is displaced according to the change in the height of the liquid surface can be smoothly transmitted to the arm holder 30, and the smooth rotation of the arm holder 30 is ensured to ensure the detection accuracy and the reliability of deformation resistance. Can be improved.
Further, since the second flat surface portion 61 is formed in a rib shape having a flat surface, it is possible to minimize an increase in the volume and weight of the frame 40, and the liquid level detection device 1A can be made smaller and lighter. The impact on can be minimized.

The second flat surface portion 61 may be formed in combination with the first flat surface portion 60 already described, thereby ensuring the detection accuracy of the liquid level detection devices 1 and 1A and the deformation resistance. The reliability of the can be ensured.

In the liquid level detecting devices 1 and 1A configured in this way, the liquid level is detected as follows.
The liquid level detection devices 1 and 1A are mounted and fixed to the mounting portion 44 of the frame 40 via the guide portion 71 of the mounting plate 70 in a state where the liquid level detecting devices 1 and 1A can be immersed in a liquid in a fuel tank (not shown).
The float 10 is displaced due to the displacement of the height of the liquid level of the liquid in the fuel tank. The displacement of the float 10 causes the arm holder 30 to rotate via the float arm 20.
Then, the electrode 51 with which the contact 46a is in contact is switched among one of the plurality of electrodes 51 on the circuit board 50, and the output signal corresponding to the position of the float 10 is transmitted to the external device via the wiring cord 47 connected to the terminal portion 46b. Output to.
The external device receives this output signal and recognizes the position of the float 10, that is, the height of the liquid level.
When the position of the float 10 is displaced, sliding contact occurs between the plurality of electrodes 51 and 52 of the circuit board 50 of the board holding portion 33 of the arm holder 30 and the contact member 46 of the frame 40, which is caused by the sliding contact. The arm holder 30 may be tilted due to the backlash of the rotating shaft O due to a reaction force or the like, but the tip portion of the radius R away from the rotating shaft O of the arm holder 30 is supported by the first flat surface portion 60 without falling into the recess. This ensures smooth rotation of the arm holder 30.
Similarly, in the liquid level detection device 1A, even if the arm holder 30 may be tilted due to the backlash of the rotation shaft O due to the reaction force due to the sliding contact between the electrodes 51 and 52 and the contact member 46, the second one. Since the facing gap d is narrowed by the flat surface portion 61, the tip portion of the arm holder 30 having a radius R away from the rotation axis O comes into contact with the second flat surface portion 61, so that the inclination is suppressed and the arm holder is smooth. 30 rotations are secured.
Therefore, the liquid level can be detected with high accuracy without deteriorating the reliability of the detection accuracy and the deformation resistance, and the liquid level detection devices 1 and 1A having excellent reliability can be obtained.

Further, by providing the first flat surface portion 60 and the second flat surface portion 61 in combination on the first flat surface portion 60, the plurality of electrodes 51 and 52 and the contact member 46 of the frame 40 are in sliding contact with each other. Even if the arm holder 30 may be tilted due to the backlash of the rotation shaft O due to the reaction force due to the above, the first flat surface portion 60 can prevent the arm holder 30 from falling into the recess, and the second flat surface portion 61 faces the arm holder 30. Since the gap d is narrowed, the arm holder 30 can rotate on the frame 40 more smoothly, and the liquid level detection device 1A with higher detection accuracy and reliability can be obtained.

As described above, together with the embodiment, as specifically described, the liquid level detection device 1 of the present invention is an arm holder (rotation) that rotates about the rotation axis O as the height of the liquid level of the liquid changes. A member) 30, a frame (support member) 40 that rotatably supports the arm holder 30, a plurality of electrodes 51 and 52 provided on the arm holder 30, and a rotation position of the arm holder 30 provided on the frame 40. The frame 40 includes a contact member 46 in which the electrodes 51 and 52 that are in sliding contact are switched among the plurality of electrodes 51 and 52, and the frame 40 faces the arm holder 30 according to the rotation position of the arm holder 30. A first flat surface portion 60 having a uniform height is provided on the surface.
According to this configuration, sliding contact occurs between the plurality of electrodes 51 and 52 of the arm holder 30 and the contact member 46 of the frame 40, and the arm holder 30 rattles on the rotation shaft O due to a reaction force due to the sliding contact or the like. Even if it is tilted due to the above, the tip portion of the radius R away from the rotation axis O of the arm holder 30 is supported by the first flat surface portion 60 without falling into the recess, and smooth rotation of the arm holder 30 is ensured. Will be done.
Therefore, the liquid level can be detected with high accuracy without deteriorating the reliability of the detection accuracy and the deformation resistance, and the liquid level detection device 1 having excellent reliability can be obtained.

The liquid level detection device 1A of the present invention rotatably supports an arm holder (rotating member) 30 that rotates about a rotation axis O as the height of the liquid level of the liquid changes, and the arm holder 30. The frame (support member) 40, the plurality of electrodes 51 and 52 provided on the arm holder 30, and the plurality of electrodes 51 and 52 provided on the frame 40 and in sliding contact with each other according to the rotation position of the arm holder 30. The frame 40 includes a contact member 46 through which the electrodes 51 and 52 are switched, and the frame 40 includes a second flat surface portion 61 that narrows the facing gap d on the facing surface facing the arm holder 30 according to the rotation position of the arm holder 30. ..
According to such a configuration, the arm holder 30 may be tilted due to the backlash of the rotation shaft O due to the reaction force due to the sliding contact between the plurality of electrodes 51 and 52 of the arm holder 30 and the contact member 46 of the frame 40. However, since the facing gap d is narrowed by the second flat surface portion 61, the tip portion of the arm holder 30 having a radius R away from the rotation axis O comes into contact with the second flat surface portion 61, so that the inclination is suppressed. This ensures smooth rotation of the arm holder 30.
Therefore, the liquid level can be detected with high accuracy without deteriorating the reliability of the detection accuracy and the deformation resistance, and the liquid level detection devices 1 and 1A having excellent reliability can be obtained.

In the liquid level detection devices 1 and 1A of the present invention, the frame 40 has a second flat surface that narrows the facing gap d on the surface of the first flat surface portion 60 facing the arm holder 30 according to the rotation position of the arm holder 30. A unit 61 is provided.
According to such a configuration, the arm holder 30 may be tilted due to the backlash of the rotation shaft O due to the reaction force due to the sliding contact between the plurality of electrodes 51 and 52 of the arm holder 30 and the contact member 46 of the frame 40. The first flat surface portion 60 can prevent the arm holder 30 from falling into the recess, and the second flat surface portion 61 narrows the facing gap d, so that the arm holder 30 rotates on the frame 40 more smoothly. It can be moved, and the liquid level detection device 1A with higher detection accuracy and reliability can be obtained.

The liquid level detection devices 1 and 1A of the present invention are not limited to the above-described embodiment, and may be appropriately modified and implemented.

In the above embodiment, the case where the mounting target and the mounting plate are separate members is illustrated, but the mounting plate may be formed integrally with the mounting target. Further, although the case where the arm holder and the seat surface portion of the shaft are the same member is illustrated, the seat surface portion of the shaft may be configured by using a metal push nut and a washer attached to the float arm. Further, although the case where the arm holding portion has a uniform surface is illustrated, the shape may be such that the float arm is held at both ends by hollowing out the central portion.

1 Liquid level detection device 10 Float 20 Float arm 21 Arm body 22 First bending part 23 Second bending part 30 Arm holder (rotating member)
31 Rotating support 31a Bearing hole 31b Shaft seat 32 Main body 33 Board holding 33a Locking 34 Arm holding 34a Grip 35 Holder side stopper 35a End face 35b End face 40 Frame (support member)
41 Frame body 42 Bearing 43 Stopper 43a Stopper surface 43b Detachment prevention section 44 Mounting section (guided section)
44a Locking part 44b Elastic part 45 Housing recess 45a Storage recess 46 Contact member 46a Contact 46b Terminal part 47 Wiring cord 50 Circuit board 51 Electrode 52 Electrode 53 Resistor 60 First flat part 60a Flat part 61 Second flat part 70 Mounting plate 71 Guide part 71a Groove 71b Engagement part O Rotating shaft

Claims (3)

A rotating member that rotates around the axis of rotation as the height of the liquid level changes,
A support member that rotatably supports the rotating member,
A plurality of electrodes provided on the rotating member and
A contact member provided on the support member and the electrodes that are in sliding contact are switched among the plurality of electrodes according to the rotation position of the rotating member.
A contact provided on the contact member and located on one end side near the rotating member, and a terminal portion located on the other end side far from the rotating member.
A housing recess provided in the support member and accommodating the contact member is provided.
The support member includes a first flat surface portion having a uniform height on a surface facing the rotating member according to the rotation position of the rotating member .
The first flat surface portion is filled with at least one corner portion of the accommodating recess on the terminal portion side.
A liquid level detection device characterized by this. In the first flat surface portion, two corner portions on the terminal portion side of the accommodating recess are filled in an arc shape.
The liquid level detection device according to claim 1. The support member includes a second flat surface portion that narrows the facing gap on the facing surface facing the rotating member according to the rotation position of the rotating member.
The liquid level detection device according to claim 1 .

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