JP2017075876A - Liquid level detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid level detector capable of suppressing deterioration in detection accuracy even if its arm interferes with a container when the liquid level detector is assembled inside the container.SOLUTION: A liquid level detector 100 includes a regulation part 18 that has an elastic portion 55 constituted to be able to elastically deform. Once an arm 50 interferes with a fuel tank 1 when the liquid level detector 100 is assembled inside the fuel tank 1, a rotation unit 30 rotates along with the arm 50. A rotational range of the rotation unit 30 is regulated by the regulation portion 18, and once force is applied in a rotating direction further by the interference of the arm 50, the elastic portion 55 included in the regulation part 18 elastically deforms, and thus, the interference of the arm 50 can be tolerated by the elastic deformation of the elastic portion 55.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a liquid level detection device that detects a liquid level of a liquid stored in a container.

  Conventionally, a liquid level detection device that detects a liquid level of a liquid stored in a container is known. In the liquid level detection device disclosed in Patent Document 1, a fixed body fixed to a container, a float floating on the liquid level, a holder held to rotate with respect to the fixed body, a holder and a float And an arm connecting the two. The vertical movement of the liquid level is transmitted to the arm by the float that floats on the liquid level. Accordingly, since the holder rotates in conjunction with the vertical movement of the liquid level, the liquid level is detected by detecting the angular displacement of the holder.

JP 2005-10093 A

  In the liquid level detection device described in Patent Document 1, the float and the holder are fixed by an arm in order to convert the vertical movement of the float into the rotational movement of the holder. If the arm is deformed for some reason, the height of the float is changed and the liquid level detection accuracy is deteriorated. Therefore, a metal having a strength that does not easily deform, such as a steel wire, is used for the arm.

  When such a liquid level detection device is assembled inside the container, it is necessary to insert an arm from the opening of the container. When the arm and the float interfere with the vicinity of the opening of the container during assembly, an excessive force may be applied to the arm and the arm may be deformed. On the other hand, a measure to improve the strength of the arm can be considered, but in the case of an assembly route that cannot be assembled unless the arm is deformed, it is necessary to deform the arm even if the strength is high. In other words, when the force applied to the arm is not a load but a displacement, that is, an interference amount, the problem cannot be solved even if the strength of the arm is improved.

  Therefore, the present invention has been made in view of the above-described problems, and provides a liquid level detection device capable of suppressing a decrease in detection accuracy even when an arm interferes with a container when the container is assembled inside the container. For the purpose.

  The present invention employs the following technical means in order to achieve the aforementioned object.

  The present invention relates to a fixed body (10) fixed to a container (1), a float (20) floating in a liquid, and a rotating body (supported by the fixed body) and rotated by the float according to the vertical movement of the liquid level. 30) and an arm (50) that connects the rotating body and the float, and the fixed body has a pair of restricting portions that restrict the rotation range of the rotating body, and the restricting portions are configured to be elastically deformable. It is a liquid level detection apparatus which has the made elastic part (55).

  According to the present invention as described above, the restricting portion has an elastic portion configured to be elastically deformable. When the liquid level detection device is attached to the inside of the container, if the arm interferes with the container, the rotating body rotates together with the arm. Although the rotation range of the rotating body is restricted by the restricting portion, if a force is further applied in the direction of rotation due to the interference of the arm, the elastic portion of the restricting portion is elastically deformed. Can be tolerated. When attaching the liquid level detection device, it is difficult to visually recognize the inside of the container, but even if the arm and the container come into contact with each other due to the elastic deformation of the elastic part, the container and the arm are not deformed. The elastic part can absorb the interference. Therefore, even if the arm is deformed by the contact of the container, it is possible to suppress a decrease in detection accuracy.

  In addition, the code | symbol in the bracket | parenthesis of each above-mentioned means is an example which shows a corresponding relationship with the specific means as described in embodiment mentioned later.

It is a front view which shows the installation state to the fuel tank 1 of the liquid level detection apparatus 100 of 1st Embodiment. 2 is a front view showing a rotating body 30 and an arm 50. FIG. It is the III-III sectional view taken on the line of FIG. 5 is a side view showing an elastic portion 55. FIG. 6 is a front view showing an elastic portion 55. FIG. It is a front view which shows the assembly | attachment state of the liquid level detection apparatus. 3 is a side view showing a spring member 70. FIG. 3 is a front view showing a spring member 70. FIG. It is a front view which shows the installation state to the fuel tank 1 of the liquid level detection apparatus 100 of 3rd Embodiment.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described using a plurality of embodiments with reference to the drawings. In some embodiments, portions corresponding to the matters described in the preceding embodiments may be given the same reference numerals, or one letter may be added to the preceding reference numerals, and overlapping descriptions may be omitted. In addition, when a part of the configuration is described in each embodiment, the other parts of the configuration are the same as those of the embodiment described in advance. In addition to the combination of parts specifically described in each embodiment, the embodiments may be partially combined as long as the combination does not hinder the combination.

(First embodiment)
A first embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 1, the liquid level detection device 100 according to the first embodiment is installed in a fuel tank 1 as a container for storing fuel as liquid. The liquid level detection device 100 detects the fuel liquid level LL while being held in the fuel pump module 2 or the like.

  The fuel pump module 2 is a device that supplies fuel to the engine. For example, a filter for fuel filtration, a pump for discharging fuel, a pressure regulator for maintaining fuel pressure, and the like are accommodated in a cylindrical cup portion. Is formed. The detection result detected by the liquid level detection device 100 is output to the ECU of the combination meter, for example, and is displayed to the driver by the combination meter as fuel remaining amount information. The liquid level detection device 100 includes a fixed body 10, a float 20, a rotating body 30, and an arm 50.

  The fixed body 10 includes a main body 12, a Hall IC 14, a terminal 16, and the like. The main body 12 of the fixed body 10 is formed of a resin material such as polyphenylene sulfide (abbreviated as PPS) resin. The main body 12 is fixed to the fuel pump module 2. Although not shown, the main body portion 12 is provided with an element storage chamber for storing the Hall IC 14, a shaft portion for rotatably supporting the rotating body 30, and the like.

  The Hall IC 14 is a detection element that detects the rotation angle of the rotating body 30 with respect to the fixed body 10. The Hall IC 14 receives a magnetic field action from the magnet 32 of the rotating body 30 to generate a voltage proportional to the density of magnetic flux passing through the Hall IC 14 in a predetermined detection direction. The three terminals 16 are formed in a band plate shape by a conductive material such as phosphor bronze. Each terminal 16 is used to transmit a detection signal between external devices (not shown) such as a combination meter and the Hall IC 14. Thus, the voltage generated in the Hall IC 14 is output to an external device as a signal indicating the detection result via each terminal 16 or the like.

  The float 20 is formed of a material having a specific gravity smaller than that of the fuel, such as foamed ebonite, and floats on the liquid level of the fuel. The float 20 is held by the rotating body 30 via the arm 50.

  The rotating body 30 is a magnet 32 holder having a main body rotating portion 34, a pair of magnets 32, and the like. The main body rotating part 34 is formed in a disk shape from a resin material such as PPS resin. The main body rotation part 34 is rotatably supported with respect to the fixed body 10 by being externally fitted to the shaft part. The main body rotation part 34 has an insertion hole 35 into which the arm 50 is inserted and a locking structure 41 that locks the arm 50.

  The pair of magnets 32 are arranged at two locations facing each other across the shaft portion in which the Hall IC 14 is accommodated. The pair of magnets 32 generates a magnetic flux that passes through the Hall IC 14. The rotating body 30 is rotated by the vertical movement of the float 20. When the float 20 is displaced according to the vertical movement of the liquid level LL, the rotating body 30 is rotated by the displacement of the float 20.

  The arm 50 is formed in a rod shape by a metal material such as a steel wire, and connects the rotating body 30 and the float 20. Specifically, one end of the arm 50 is inserted through a through hole 22 formed in the float 20. The other end of the arm 50 is attached to the rotating body 30. The arm 50 includes a locking portion 52 that is locked by the locking structure 41 of the rotating body 30, and an insertion portion 54 that is bent with respect to the locking portion 52 and inserted into the insertion hole 35.

  Next, the relationship between the rotating body 30 and the arm 50 attached to the rotating body 30 will be described in detail with reference to FIGS. 2 and 3. The locking portion 52 of the arm 50 extends along a predetermined extending direction DE. The insertion hole 35 is opened through the hole axis substantially perpendicular to the extending direction DE. In the present embodiment, three insertion holes 35 are provided side by side along the extending direction DE. The insertion portion 54 of the arm 50 is inserted into any one of the three insertion holes 35. In the drawing, an insertion portion 54 is inserted into the second insertion hole 35 from the outer peripheral side of the rotating body 30.

  The locking structure 41 formed integrally with the main body rotating part 34 is composed of two same-diameter clamps 41a and 41b, one small-diameter clamp 41c and a locking stopper 41d, which are arranged side by side in the extending direction DE. ing. As shown in FIGS. 2 and 3, the two same diameter clamps 41 a and 41 b arranged closest to the insertion hole 35 are formed with the same diameter as the diameter of the locking portion 52 of the arm 50 and bent. The locking portion 52 is locked from the side opposite to the side and the side opposite to the receiving side.

  The small-diameter clamp 41c is formed to have a diameter slightly smaller than the diameter of the engaging portion 52 of the arm 50, and in an elastically deformed state, the engaging portion 52 is moved from the opposite side to the bending side and the receiving side. Lock. Here, the receiving side is the side where the same-diameter clamps 41 a and 41 b and the small-diameter clamp 41 c are released in the locking structure 41.

  As shown in FIGS. 2 and 3, the locking stopper 41 d locks from the receiving side that the locking portion 52 rotates and comes off the clamps 41 a to 41 c. Since a plurality of the clamps 41 a to 41 c are provided, even if the main body rotating unit 34 is distorted during use of the liquid level detection device 100, the mounted state is reliably maintained.

  The locking portion 52 of the arm 50 is extended along the surface of the main body rotating portion 34 by being locked to the locking structure 41. The insertion portion 54 of the arm 50 is bent with respect to the locking portion 52 and is inserted into the insertion hole 35. More specifically, the bent portion 56 between the locking portion 52 and the insertion portion 54 is curved because it is formed by processing using a bending die. The insertion portion 54 is bent at a right angle with respect to the locking portion 52.

  Further, the distal end of the insertion portion 54 protrudes from the insertion hole 35. The distal end of the insertion portion 54 abuts against the pair of restricting portions 18 of the fixed body 10 to restrict the rotation angle of the rotating body 30. Therefore, the restricting unit 18 restricts the rotation range of the rotating body 30. Here, the pair of restricting portions 18 that are in contact with each other by the three insertion holes 35 are formed so as to be different from each other, and the tip of the insertion portion 54 rotates as it is inserted into the insertion hole 35 on the outer peripheral side of the rotating body 30. The deflection angle of the body 30 is small. Here, the deflection angle is an angle corresponding to between the restricting portions 18 on both sides corresponding to the distal end of the insertion portion 54. That is, the insertion hole 35 for inserting the arm 50 is selected in accordance with the shape of the fuel tank 1 to be installed.

  The restricting portion 18 has an elastic portion 55 configured to be elastically deformable. The elastic portion 55 is provided in the restriction portion 18 on the side that restricts the rotation range of the rotating body 30 when the float 20 is displaced downward, that is, the restriction portion 18 on the right side in FIG. As shown in FIGS. 2 and 4, the elastic portion 55 is configured integrally with the fixed body 10 together with the restricting portion 18.

  As shown in FIGS. 4 and 5, the elastic portion 55 is realized by a protruding piece 55 a partially protruding from the wall surface of the restricting portion 18. The protruding piece 55a extends in an oblique direction from the wall surface of the restricting portion 18. Therefore, one end of the base of the protruding piece 55a is supported on the wall surface of the restricting portion 18 like a cantilever. As a result, the tip of the protruding piece 55a is elastically deformed with the root as a fulcrum as shown by the arrow in FIG.

  In order to form such a protruding piece 55a in the restricting portion 18, as shown in FIG. 5, a slit 18b is formed in a part of the wall surface of the restricting portion 18 that is connected to the bottom surface. By forming the slit 18b, the projecting piece 55a is separated from the bottom surface and can be elastically deformed.

  Next, attachment of the liquid level detection device 100 as described above into the fuel tank 1 will be described with reference to FIG. The fuel tank 1 has an opening 2a for assembling the fuel pump module 2 therein. The opening 2 a of the fuel tank 1 has a size that can pass through the outer shape of the fuel pump module 2 indicated by the phantom line in FIG. 6 and can be closed by the lid portion 2 b at the top of the fuel pump module 2. However, since the float 20 and the arm 50 protrude outward from the outer shape of the fuel pump module 2, when assembling, the fuel pump module 2 is tilted and the float 20 is first inserted from the opening 2a. Then, as shown in FIG. 6, the fuel pump module 2 is made to enter the fuel tank 1 while rotating in the direction indicated by the arrow in FIG.

  When the fuel pump module 2 is thus rotated, the float 20 may come into contact with the fuel tank 1 depending on the shape of the fuel tank 1 as indicated by a broken line in FIG. When the float 20 comes into contact with the fuel tank 1 and a force acts in the direction of the arrow that pushes the float 20 down, the force also acts on the arm 50 from the float 20. When a force in a direction of pushing down the arm 50 is applied, the rotating body 30 rotates counterclockwise in FIG. Then, the tip of the arm 50 comes into contact with the elastic portion 55 of the restricting portion 18. When the arm 50 is further pushed down by contacting the fuel tank 1 in the contact state, the elastic portion 55 is elastically deformed. Therefore, the assembly operation can be continued without damaging the arm 50, and the fuel pump module 2 can be disposed inside the fuel tank 1.

  As described above, the liquid level detection device 100 of the present embodiment has the elastic portion 55 in which the restricting portion 18 is configured to be elastically deformable. When mounting the liquid level detection device 100 inside the fuel tank 1, if the arm 50 interferes with the fuel tank 1, the rotating body 30 rotates together with the arm 50. Although the rotation range of the rotating body 30 is restricted by the restricting portion 18, if a force is further applied in the direction of rotation due to the interference of the arm 50, the elastic portion 55 of the restricting portion 18 is elastically deformed, so that the arm 50 interferes. It can be permitted by elastic deformation of the elastic portion 55. When the liquid level detection device 100 is attached, it is difficult to visually recognize the inside of the fuel tank 1, but the elastic portion 55 is elastically deformed, so that the arm 50 is deformed even if the arm 50 and the fuel tank 1 come into contact with each other. The elastic portion 55 can absorb the interference without causing the interference. Therefore, even if the arm 50 is deformed by the contact of the fuel tank 1, it is possible to prevent the detection accuracy from being lowered.

  In other words, in the present embodiment, the restricting portion 18 formed on the fixed body 10 is configured not to be a plastic portion but to bend more than a certain load. As a result, the displacement due to the interference of the arm 50 or the like is absorbed not on the arm 50 but on the fixed body 10 side, that is, the arm 50 and the rotating body 30 can be further rotated from the empty position of the lower limit position.

  In the present embodiment, of the pair of restricting portions 18, the restricting portion 18 that restricts the rotation range of the rotating body 30 when the float 20 is displaced downward includes the elastic portion 55. When the liquid level detection device 100 is assembled, as shown in FIG. 6, when the float 20 and the arm 50 are displaced downward, the elastic portion 55 is provided only on one of the regulating portions 18. The interference of the arm 50 can be allowed. Therefore, the structure of the fixed body 10 can be simplified as compared with the case where the elastic portions 55 are provided in both of the pair of restricting portions 18.

  Further, in the present embodiment, the elastic portion 55 is configured integrally with the fixed body 10 together with the restricting portion 18. Since the elastic portion 55 can be realized by integral molding, manufacturing is easy.

  In the present embodiment, the protruding tip of the arm 50 is regulated by the regulating unit 18. The arm 50 preferably has a strength that does not deform due to a stress necessary for elastically deforming the elastic portion 55. As a result, the arm 50 can be prevented from being deformed even if the tip of the arm 50 comes into contact with the elastic portion 55 and is elastically deformed. On the contrary, if the stress necessary for elastically deforming the elastic portion 55 is high, the arm 50 may be deformed first before reaching the elastic deformation stress. Therefore, it is preferable to define the elastic force of the elastic portion 55 so that the arm 50 is not deformed. If the stress required for the elastic deformation of the elastic portion 55 is too small, the elastic portion 55 is further moved by vibration, float 20 and the weight of the arm after the liquid level LL reaches the lower limit after the liquid level detecting device 100 is installed. There is a risk of elastic deformation. If it does so, the float 20 will fall further below the lower limit position of the liquid level LL, and will contact the bottom face of the fuel tank 1, and there exists a possibility that the float 20 and the arm 50 may be damaged. Therefore, the stress necessary for elastic deformation of the elastic portion 55 is set to a stress that does not elastically deform even when at least the fuel in the fuel tank 1 is absent and the weight of the arm 50 and the float 20 acts on the elastic portion 55.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS. The present embodiment is characterized in that the elastic portion 55 is configured by a metal spring member 70 that is separate from the restricting portion 18. As shown in FIG. 7, the restricting portion 18 is formed with a concave portion 18 a that is a concave portion.

  The spring member 70 includes a plate-like base 71, a spring portion 72, and a contact portion 73. A base 71 of the spring member 70 is provided in the recess 18a. The plate-like base 71 is provided with a spring portion 72 and a contact portion 73.

  The contact portion 73 has elasticity and is provided on the back side of the base 71, that is, on the left side in FIG. The contact portion 73 is inserted into the concave portion 18a in an elastically denatured state. As a result, the contact portion 73 urges the base 71 to the right in FIG. 7 by elastic force, so that the base 71 is fixed to the recess 18a.

  The spring portion 72 protrudes from the base 71 and extends in an oblique direction. Therefore, one end of the base of the spring portion 72 is supported by the base 71 like a cantilever beam. As a result, the tip of the spring portion 72 is elastically deformed with the root as a fulcrum as shown by the arrow in FIG.

  Thus, in the present embodiment, the metal spring member 70 is provided in the recess 18 a formed in the restricting portion 18. As a result, it is only necessary to provide the spring member 70 only at a necessary portion, so that the configuration can be simplified. Moreover, since the structure of the spring member 70 should just be changed according to a required spring force, adjustment of a spring force also becomes easy.

(Third embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. The present embodiment is characterized in that not the tip of the arm 50 but the rotating body 30 is restricted by the restricting portion 18. As shown in FIG. 9, the fixed body 10 is integrally provided with an L-shaped elastic portion 550.

  The side surface of the rotator 30 is in contact with the restricting portion 18 to restrict the rotation range. When the tip of the elastic portion 550 and the rotating body 30 are in contact with each other and the rotation is restricted, when the float 20 is further pushed down, the elastic portion 550 is elastically deformed. As a result, the interference of the arm 50 during assembly can be allowed. Moreover, in this embodiment, since the arm 50 does not contact the control part 18, it can suppress that the arm 50 contacts the elastic part 550 and deform | transforms.

(Other embodiments)
The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

  The structure of the said embodiment is an illustration to the last, Comprising: The scope of the present invention is not limited to the range of these description. The scope of the present invention is indicated by the description of the scope of claims, and further includes meanings equivalent to the description of the scope of claims and all modifications within the scope.

  In the first embodiment described above, the elastic portion 55 is provided on the side that restricts the rotation of the rotating body 30 when the float 20 is lowered, but the elastic portion 55 may be provided on the opposite-side restricting portion 18. Good. Thereby, the versatility of the mounting direction of the liquid level detection apparatus 100 can be improved. Therefore, the elastic portion 55 can be made to function even when the mounting direction or the like changes depending on the shape of the fuel tank 1.

  In the first embodiment described above, the liquid level detection device 100 detects the liquid level LL of the fuel, but is not limited to the fuel. It may be applied to the liquid level detection device 100 that detects the liquid level LL of other liquids mounted on the vehicle, such as brake fluid, engine cooling water, engine oil and the like. Furthermore, the present invention is applicable not only to vehicles but also to liquid level detection devices provided in containers provided in various consumer devices and various transport devices.

  In the first embodiment described above, the liquid level detection device 100 detects the liquid level based on the change in magnetic flux density. However, the configuration is not limited to such a configuration. For example, it may be a variable resistance type liquid level detection device using a variable resistor, or may be configured to detect angular displacement of other rotating bodies 30.

LL ... Liquid level 1 ... Fuel tank (container) 2 ... Fuel pump module 2a ... Opening 2b ... Cover part 10 ... Fixed body 12 ... Main body 18 ... Restriction part 18a ... Recess 20 ... Float 30 ... Rotating body 32 ... Magnet 34 ... Main body rotation part 35 ... Insertion hole 41 ... Locking structure 50 ... Arm 52 ... Locking part 54 ... Insertion part 55 ... Elastic part 55a ... Projection piece 56 ... Bending part 70 ... Spring member 71 ... Base body 72 ... Spring part 73 ... Contact part 100 ... Liquid level detector

Claims (5)

A liquid level detection device (100) for detecting a liquid level (LL) of a liquid stored in a container (1),
A fixed body (10) fixed to the container;
A float (20) floating in the liquid;
A rotating body (30) supported by the fixed body and rotated by the float according to the vertical movement of the liquid level;
An arm (50) for connecting the rotating body and the float,
The fixed body has a pair of restricting portions that restrict the rotation range of the rotating body,
The regulation part is a liquid level detection device having an elastic part (55) configured to be elastically deformable.   The liquid level detection device according to claim 1, wherein, of the pair of restriction portions, the restriction portion on a side that restricts a rotation range of the rotating body when the float is displaced downward includes the elastic portion.   The liquid level detection device according to claim 1, wherein the elastic part is configured integrally with the fixed body together with the restriction part.   The liquid level detection device according to claim 1, wherein the elastic portion is configured by a spring member (70) attached to the restricting portion. The arm is fixed so that a part protrudes from the rotating body,
The protruding part of the arm is regulated by the regulating part,
The liquid level detection device according to claim 1, wherein the arm has a strength that does not deform due to a stress necessary for elastically deforming the elastic portion.

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