JP4923822B2 - Liquid level detecting device and manufacturing method thereof - Google Patents

Description

  The present invention relates to a liquid level detection device for detecting a liquid level in a tank and a method for manufacturing the same.

  In order to monitor the level of fuel or the like stored in a fuel tank of an automobile, for example, a liquid level detection device including a magnetoelectric conversion element is used.

  This liquid level detection device is connected to a main body part, a float floating on the liquid surface, a rotating part rotatable with respect to the main body part, and the float and the rotating part to connect the float and the rotating part to the rotary motion of the rotating part. Arm, a magnet built in the rotating part, and a magnetoelectric conversion element (see Patent Document 1 and Patent Document 2).

  The magnetoelectric conversion element is built in the main body, and detects the rotation angle of the rotating portion relative to the main body by measuring the magnetic flux density of the magnet. Thereby, the liquid level detection apparatus can detect a liquid level.

  Further, a terminal for electrically connecting the magnetoelectric conversion element to the outside is built in the main body, and a general capacitor or resistor having a lead wire is electrically connected to the terminal and built in the main body. A terminal to which a magnetoelectric conversion element, a capacitor, and a resistor are connected is insert-molded in the main body when the main body is molded with resin.

Thereby, while improving the vibration resistance of a liquid level detection apparatus, the output change resulting from the change of use environment temperature can be reduced, and the detection accuracy can be maintained highly accurately and stably over a long period of time.
JP 2004-251780 A JP 2004-152546 A

  Although not described in Patent Document 1 and Patent Document 2, this capacitor or resistor generally protects the magnetoelectric conversion element electrically. Specifically, the capacitor prevents the magnetoelectric conversion element from being electrically damaged by high voltage pulses such as static electricity, and the resistor prevents the overcurrent from flowing through the magnetoelectric conversion element. .

  However, a general capacitor or resistor having a lead wire has a large physique, which causes a problem when the liquid level detection device is downsized. In particular, this is contrary to the demand for downsizing the liquid level detection device for vehicles.

  On the other hand, when a chip element including a chip capacitor or a chip register is used, the chip element may be mechanically damaged, such as being cracked by a molding pressure during resin molding of the main body.

  Moreover, it is not limited to the external force due to the molding pressure, and there is a risk of mechanical damage such as cracking due to external force due to vibration of the host vehicle or external force due to other causes.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a liquid level detection apparatus that can prevent mechanical damage to a chip element and a method for manufacturing the same in a liquid level detection apparatus including a chip element. .

  The present invention employs the following technical means to achieve the above object.

According to a first aspect of the present invention, there is provided a liquid level detecting device, comprising: a resin-molded main body part; a float floating on the liquid surface; a rotating part rotatable with respect to the main body part; and the float and the rotating part. Then, the rotation angle of the rotating part with respect to the main body part by measuring the magnetic flux density of the magnet built in the rotating part, the magnet built in the rotating part, and the arm that converts the vertical movement of the float into the rotating movement of the rotating part A magnetoelectric conversion element for detecting the magnetic field, a terminal that is built in the main body and electrically connects the magnetoelectric conversion element to the outside, and a chip element that is electrically connected to the terminal and electrically protects the magnetoelectric conversion element, the terminal holder is formed of resin is fixed so as to cover both the front and back surfaces in part of the terminal, holder has a recess formed so as to expose the surface of the terminal, the chip element Is electrically connected to the terminal in the recess while being housed in portion, is secured in a holder and terminal chip device is connected is insert molded into the body portion, the holder recess is formed by insert molding A convex portion is provided at a position opposite to the opposite side and facing the chip element, and the surface of the tip portion of the convex portion is substantially flush with the surface of the main body portion .

When insert molding in a fixed and a terminal chip device is connected the body portion in the holder, the terminal and the chip element is subjected to pressure by the resin injected into the mold.

According to the configuration described above, the terminal can be inserted formed shape is integral with the holder in the holder. In this case, the bonding strength between the terminal and the holder is significantly improved in comparison with the case of mechanically securing the terminal to the forming shape has been the holder as a separate component. Accordingly, the and the chip element are fixed in the holder is connected terminal when insert molding within the body portion receives an injection resin pressure can be prevented that the terminal is deformed.

Further, according to the above-described configuration, the recess is provided in the holder so as to expose the surface of the terminal, and the chip element is electrically connected to the terminal in the recess and accommodated in the recess. Thus, when insert molding the fixed and terminal chip device is connected to the holder within the body portion, it is prevented that the resin flow that has flowed into the cavity of the mold collides with the direct chip element. Therefore, it is possible to prevent the chip element from being damaged due to the injection resin pressure.

Further, when insert-molding a terminal fixed in the holder and connected to the chip element into the main body, the force due to the injected resin pressure acting on the chip element directs the chip element toward the bottom of the concave portion of the holder, that is, the terminal side. Acts like pressing. Therefore, according to the configuration described above, the convex portion of the holder is in contact with the mold in the cavity of the mold for molding the main body. For this reason, the force due to the injected resin pressure acting on the chip element is transmitted to the convex portion of the holder through the chip element and the terminal, and further to the mold. Since the mold has high rigidity and does not deform, it is possible to suppress deformation of the terminal and the holder.

The liquid level detection apparatus according to claim 2 of the present invention is characterized in that an adhesive is filled between the back surface, which is the surface on the terminal side of the chip element, and the surface of the holder facing the back surface. When there is a space between the back surface on the terminal side of the chip element and the surface of the holder facing the back surface, when insert molding the terminal fixed in the holder and connected to the chip element into the main body, The stress generated in the chip element due to the injection resin pressure acting on the chip element is partially excessive, and the chip element may be deformed and damaged. By filling the space with an adhesive, the chip element can be prevented from being damaged by uniformizing the magnitude of the stress generated in the chip element when the chip element receives the injection resin pressure.

The liquid level detecting device according to claim 3 of the present invention is characterized in that the recess is filled with a resin material . According to this configuration, the chip element is covered with the resin material . For this reason, when the terminal fixed in the holder and connected to the chip element is insert-molded in the main body, the injected resin does not directly touch the chip element. Therefore, it is possible to prevent the chip element from being damaged by receiving the fluid force of the injected resin or being damaged by receiving the heat of the injected resin. Further, since the resin material in the recess is filled, the resin material may, until fully cured, does not flow out into the recess outside could not get the wall of the recess. Therefore, the chip element can be reliably covered with the resin material .

According to a fourth aspect of the present invention, there is provided a liquid level detection device comprising: a protective resin portion that is formed of a resin material filled in a recess and covers a surface of a chip element that is not supported by a holder and a connection portion of the chip element to a terminal. It is set as the structure provided. Thereby, a chip element and a connection part can be protected from the molding heat at the time of insert molding, obtaining the above-mentioned effect.
The liquid level detection apparatus according to claim 5 of the present invention is characterized in that the chip element is at least one of a chip capacitor and a chip register. This makes it possible to reduce the thickness of the terminal in the thickness direction and reduce the thickness of the main body, while preventing high-voltage pulses such as static electricity from flowing into the magnetoelectric transducer from the outside, or preventing overcurrent from flowing into the magnetoelectric transducer. it can.

In the liquid level detection apparatus according to the sixth aspect, the holder includes a protective case portion that covers and protects the magnetoelectric conversion element connected to the terminal. In this configuration, since the magnetoelectric conversion element is covered and protected by the protective case portion of the holder at the time of insert molding, thermal damage due to insert molding can be prevented while obtaining the above-described effects.

Method for producing a liquid level detecting apparatus according to claim 7 of the present invention is a manufacturing method for liquid level detection device according to any one of claims 1 to 6, the holder is molded of a resin material a connecting step of connecting the first forming shapes step of fixing in the holder, after the first forming shaped step disposed chip element in the recess of the holder and electrically to the terminal a terminal by insert formed shape when, body the parts when molding a resin material, the finished holder connecting step and a second forming shape steps you insert molded into the body portion, in the second forming shape step, the holder of the mold main body cavity The convex portion is held in contact with the molding die inside.

Thus, the terminal fixed and chip elements are connected to the holder at the time of insert molding into the body portion receives an injection resin pressure method for manufacturing a preventable liquid level detecting device that terminals are deformed Can be provided.

  Hereinafter, a case where the liquid level detection device according to the present invention is applied to a fuel level gauge 1 which is a liquid level detection device mounted on an automobile will be described with reference to the drawings.

(Constitution)
FIG. 1 is a front view of a fuel level gauge 1 which is a liquid level detection device according to an embodiment of the present invention.

  2 is a cross-sectional view taken along line II-II in FIG.

  3 is a cross-sectional view taken along line III-III in FIG.

  FIG. 4 is a schematic diagram for explaining the magnetic flux distribution of the magnet 6 shown in FIG.

  FIG. 5 is a V arrow view of the terminal 8 shown in FIG.

  6 is a cross-sectional view taken along line VI-VI in FIG.

  FIG. 7 is a cross-sectional view of the detection unit 7.

  FIG. 8 is a cross-sectional view of the main body 5 shown in FIG.

  FIG. 9 is a circuit configuration diagram illustrating an electrical circuit configuration of the fuel level gauge 1 according to the embodiment of the present invention.

  1 and 2, the upper part indicated by the arrow in each figure indicates the upper part in a state where the fuel level gauge 1 is attached to the automobile.

  1 and 2, the fuel level gauge 1 detects the level of the liquid level A1 of the fuel A in a fuel tank (not shown), and is fixed in the fuel tank.

  The float 2 is made of resin or the like, and has an apparent specific gravity so as to be surely floated on the liquid level A1 of the fuel A.

  The arm 3 is formed of, for example, a metal rod, and connects the float 2 and the rotating unit 4. As shown in FIG. 1, the float 2 is fixed to one end portion of the arm 3, and the other end portion of the arm 3 is fixed to the rotating portion 4. When the float 2 moves in the vertical direction (the vertical direction indicated by the arrow in the figure) according to the fluctuation of the level of the liquid level A1, this movement is transmitted to the rotating part 4 by the arm 3 and is caused to rotate in the rotating part 4 Converted.

  As shown in FIG. 2, the rotating part 4 is made of a resin material so as to incorporate a magnet 6 and to be rotatably engaged with a main body part 5 described later. As shown in FIGS. 1 and 2, the rotating portion 4 includes a hole portion 41 that is rotatably fitted to a shaft portion 51 provided in the main body portion 5, and a holding portion 42 that holds and fixes the arm 3. And a through hole 43.

  Two holding portions 42 are arranged on the end surface of the rotating portion 4 opposite to the main body portion 5 (the left surface in FIG. 2), and are formed as shown in FIG. FIG. 3 shows a state in which the arm 3 is not attached, and the arm 3 is indicated by a one-dot chain line.

  The holding part 42 has an inner diameter dimension D2 smaller than the outer diameter dimension D1 of the arm 3, and an opening dimension W of the insertion port 42a of the holding part 42 smaller than the inner diameter dimension D2. The two holding portions 42 are arranged with their central axes aligned.

  As shown in FIGS. 1 and 2, the through hole 43 is formed in parallel with the hole 41 of the rotating unit 4. The inner diameter dimension of the through hole 43 is equal to or slightly smaller than the outer diameter dimension D1 of the arm 3. As shown in FIG. 1, the through-hole 43 is arranged so that its central axis intersects with the central axes of both holding portions 42.

  The magnet 6 built in the rotating unit 4 is made of, for example, a ferrite magnet, and is a cylindrical type, and is disposed concentrically with the hole 41. Furthermore, since the magnet 6 is magnetized in the radial direction as shown in FIG. 4, the magnetic flux of the magnet 6 is generated in the radial direction of the hole 41. The magnet 6 is integrally insert-molded when the rotating part 4 is resin-molded. At the time of molding, the holding portion 42 is also formed.

  The main body 5 includes a Hall integrated circuit (Hall IC) 70 that is a magnetoelectric conversion element that detects the rotation angle of the rotating unit 4 and a terminal 8 for electrically connecting the Hall IC 70 to the outside.

  As shown in FIG. 5, the terminal 8 includes a signal terminal 81 for a measurement signal of the Hall IC 70, a ground terminal 82 for grounding the Hall IC 70, and a power supply terminal 83 for powering the Hall IC 70.

  The terminal 8 is formed of a conductive metal, and one end thereof is electrically connected to the leads 71-73 of the Hall IC 70 as shown in FIGS. The signal terminal 81 is connected to the signal lead 71, the ground terminal 82 is connected to the ground lead 72, and the power terminal 83 is connected to the power lead 73. These connections are, for example, by caulking or welding.

  On the other hand, the other end of the terminal 8 protrudes outward from the end of the main body 5 and is connected to a connector (not shown) of an external wire harness (not shown). 9) is electrically connected.

  As shown in FIG. 2, the Hall IC 70 is disposed in the shaft portion 51, and the magnet 6 fixed to the rotating portion 4 is disposed concentrically with the shaft portion 51 on the outer peripheral side of the shaft portion 51. For this reason, the Hall IC 70 always receives the magnetic flux M of the magnet 6 as shown in FIG.

  The Hall IC 70 incorporates a Hall element made of a semiconductor (not shown) and a preamplifier. When a magnetic field is applied from the outside in a state where a voltage is applied to the Hall element, the Hall element generates a Hall voltage proportional to the magnetic flux density of the magnetic field passing through the Hall element. This Hall voltage is amplified by a preamplifier or the like and transmitted to the control device 21.

  The power supply terminal 83 is a terminal for applying a driving voltage to the Hall element and the preamplifier of the Hall IC 70, and the signal terminal 81 transmits the Hall voltage of the Hall element via the preamplifier and the like. It is a terminal for transmitting to the control apparatus 21 (FIG. 9).

  That is, a voltage is applied to the Hall element via the power supply terminal 83 and the power supply lead 73, and in this state, a magnetic field is applied from the outside to generate a Hall voltage. The Hall voltage is amplified by a preamplifier or the like that is driven by being applied with a voltage via a power terminal 83 and a power lead 73, and is sent to the control device 21 via a signal terminal 81 and a signal lead 71. Communicated.

  Since the magnetic flux density of the magnetic field passing through the Hall element (Hall IC 70) changes when the rotating unit 4 rotates due to the fluctuation of the liquid level A1, the Hall voltage of the Hall element, that is, the output voltage of the Hall IC 70 changes accordingly. . By detecting the output voltage of the Hall IC 70 (Hall voltage of the Hall element), the rotation angle of the rotating unit 4, that is, the level of the liquid level A1 can be measured.

  Hereinafter, a mounting structure of a chip capacitor 9 which is a chip element that is insert-molded and incorporated, which is a feature of the present invention, will be described.

  The two chip capacitors 9 as the first chip capacitor and the second chip capacitor that electrically protect the Hall IC 70 are soldered to the mounting seat 85 of the terminal 8 and are electrically connected to the terminals 81-83. . The chip capacitor 9 is, for example, a multilayer capacitor having a capacity of 4.7 nanofarad (nF), and one end of the chip capacitor 9 is electrically connected to the ground terminal 82. The other end of the chip capacitor 9 is It is electrically connected to the terminal 81. One end of the other chip capacitor 9 is electrically connected to the ground terminal 82, and the other end of the chip capacitor 9 is electrically connected to the power supply terminal 83.

  When a high voltage pulse such as static electricity is applied to the signal terminal 81 and the power supply terminal 83, a preamplifier (not shown) of the Hall IC 70 may be electrically damaged. However, since the high voltage pulse flows out to the ground terminal 82 via the chip capacitor 9, it is not applied to the preamplifier or the like of the Hall IC 70. Thereby, it is possible to prevent the preamplifier of the Hall IC 70 from being electrically damaged.

  Since the chip capacitor 9 is smaller than a general capacitor having a lead wire, the chip capacitor 9 does not hinder downsizing of the fuel level gauge 1.

  As shown in FIG. 7, the holder 10 fixed to the terminal 8 and supporting the chip capacitor 9 is configured such that the chip capacitor 9 electrically connected to the terminal 8 is supported by the holder 10 fixed to the terminal 8. Configured. The holder 10 is made of polyphenylene sulfide (PPS), which is a high heat resistant resin. The holder 10 includes a capacitor support portion 11 that is an element support portion that supports the chip capacitor 9, a mold support portion 12 that is supported by a mold during insert molding, and a protective case portion 13 that covers and protects the Hall IC 70. .

  After the lead 7 of the Hall IC 70 is electrically connected (welded or the like) to the terminal 8, the holder 10 is fixed to the terminal 8 by heat caulking or press-fitting in the fixing hole 84 of the terminal 8. Thereafter, the chip capacitor 9 is soldered to the mounting seat 85 of the terminal 8 so that the chip capacitor 9 is supported by the capacitor support portion 11 of the holder 10.

  The mounting seat 85 is formed to be recessed on the left side in FIGS. 6 and 7, and an epoxy resin or the like is applied from the right side in FIG. 7 in order to protect the chip capacitor 9 and the solder portion 92 from the molding heat at the time of insert molding. This is solidified to form the protective resin portion 91. In this way, the detection unit 7 shown in FIG. 7 is formed.

  The terminal 8 to which the Hall IC 70 is connected, the holder 10 is fixed, and the chip capacitor 9 is connected, that is, the detection unit 7 in which these are integrated, is insert-molded into the main body 5 during resin molding of the main body 5. Thus, the main body 5 shown in FIG. 8 is formed.

  Thereby, at the time of insert molding, the holder 10 of the holder 10 is supported by the mold, and the chip capacitor 9 is supported by the capacitor support 11 of the holder 10 supported by the mold. As a result, the chip capacitor 9 receives a molding pressure at the time of insert molding. However, since the chip capacitor 9 is supported by the capacitor support portion 11 of the holder 10, mechanical damage to the chip capacitor 9 due to this molding pressure can be prevented.

  Further, the terminal 8 is also supported by a holder 10 supported by a mold. As a result, the terminal 8 is also subjected to molding pressure at the time of insert molding, but is supported by the holder 10, so that deformation due to the molding pressure is prevented, and mechanical damage to the chip capacitor 9 due to deformation of the terminal 8 can be prevented. .

  Moreover, since Hall IC70 is covered and protected by the protective case part 13 of the holder 10 at the time of insert molding, it can prevent the thermal damage by insert molding.

  Moreover, an epoxy resin is applied and solidified from the right side in FIG. 7 to form the protective resin portion 91. For this reason, the chip capacitor 9 and the solder portion 92 can be protected from the molding heat at the time of insert molding.

  As shown in FIGS. 2 and 8, the main body portion 5 formed in this way includes a shaft portion 51, and the shaft portion 51 rotatably holds the rotating portion 4. In the vicinity of the tip of the shaft portion 51, a ring-shaped groove 52 is provided concentrically with the shaft portion 51. After the shaft portion 51 is fitted into the hole portion 41 of the rotating portion 4, a retaining ring 53 is attached to the groove 52. Thereby, the movement to the direction which leaves | separates the main-body part 5 of the rotation part 4 (left direction which the arrow of FIG. 2 shows) is controlled.

  That is, the shaft portion 51 of the main body portion 5 is inserted into the hole portion 41 of the rotating portion 4, the rotating portion 4 is brought into contact with the main body portion 5, and the retaining ring 53 is attached to the groove 52 of the shaft portion 51. Thereby, the rotating part 4 is held rotatably with respect to the main body part 5.

  After inserting the arm 3 into the through hole 43, the arm 3 is rotated around the through hole 43, and the arm 3 is pushed into the holding portion 42 from the left side indicated by the arrow in FIG. As a result, the holding portion 42 is elastically deformed to hold and fix the arm 3, thereby fixing the arm 3 to the rotating portion 4.

  The electric circuit configuration of the fuel level gauge 1 according to the present embodiment described above will be described with reference to FIG.

  The control device 21 constituted by a microcomputer or the like is always supplied with electric power from the battery 24, and the ignition switch 23 is connected so as to detect its operation position (off position, on position). A fuel gauge 22 is also connected to the control device 21.

  The control device 21 supplies power to the fuel level gauge 1 (Hall IC 70) via the power supply terminal 83, receives a detection signal from the fuel level gauge 1 via the signal terminal 81, and based on this signal, the fuel gauge 22 Is to operate.

  The signal terminal 81 and the power supply terminal 83 are grounded via the ground terminal 82 by the chip capacitor 9.

  The combination meter 20 includes a control device 21 and a fuel gauge 22.

(Operation)
Next, the operation of the fuel level gauge 1 which is a liquid level detection device according to an embodiment of the present invention will be described.

  In FIG. 9, when the ignition switch 23 is turned on, the control device 21 detects it and starts its operation, and supplies power to the fuel level gauge 1 (Hall IC 70) via the power terminal 83. Operate. The Hall IC 70 that has started operation outputs a signal corresponding to the level of the liquid level A1 to the control device 21 via the signal terminal 81. The control device 21 receives this signal and operates the fuel gauge 22 based on this signal.

  Here, even if a high voltage pulse such as static electricity is generated and applied to the signal terminal 81 or the power supply terminal 83, it flows out to the ground terminal 82 via the chip capacitor 9. As a result, the high-voltage pulse is not applied to the preamplifier of the Hall IC 70, so that the preamplifier of the Hall IC 70 can be prevented from being damaged electrically.

  Further, the chip capacitor 9 is smaller in size than a general capacitor having a lead wire, so that the miniaturization of the fuel level gauge 1 is not hindered.

  The Hall IC 70, the terminal 8, and the chip capacitor 9 are insert-molded in the main body 5 when the main body 5 is molded with resin. Thereby, while improving the vibration resistance of the fuel level gauge 1, the output change resulting from the change of use environment temperature can be reduced, and the detection accuracy can be maintained highly accurately and stably over a long period of time.

  As described above, the holder 10 includes the capacitor support portion 11 that supports the chip capacitor 9, the mold support portion 12 that is supported by the mold during insert molding, and the protective case portion 13 that covers and protects the Hall IC 70. . Thereby, the chip capacitor 9 receives a molding pressure at the time of insert molding. However, since the chip capacitor 9 is supported by the capacitor support portion 11 of the holder 10, mechanical damage to the chip capacitor 9 due to the molding pressure can be prevented.

  Furthermore, since the terminal 8 is also supported by the holder 10, the deformation of the terminal 8 due to the molding pressure at the time of insert molding is prevented, and mechanical damage to the chip capacitor 9 due to this deformation can be prevented.

  Moreover, since Hall IC70 is covered and protected by the protective case part 13 of the holder 10, the thermal damage by insert molding can be prevented. Further, since the protective resin portion 91 shown in FIG. 7 is formed, the chip capacitor 9 and the solder portion 92 can be protected from the molding heat at the time of insert molding.

  As described above, the fuel level gauge 1 which is the liquid level detection device according to the embodiment of the present invention includes the main body part 5, the float 2 floating on the liquid surface, the rotating part 4 rotatable with respect to the main body part 5, and the float. 2 and the rotating part 4 are coupled to convert the vertical movement of the float 2 into the rotating movement of the rotating part 4, the magnet 6 incorporated in the rotating part 4, and the magnetic flux of the magnet 6 incorporated in the main body part 5. Hall IC 70 that is a magnetoelectric conversion element that detects the rotation angle of rotating portion 4 with respect to main body 5 by measuring the density, terminal 8 that is built in main body 5 and electrically connects Hall IC 70 to the outside, and terminal 8 A chip capacitor 9 that is electrically connected to the Hall IC 70 and a holder 10 that is fixed to the terminal 8 and supports the chip capacitor 9 connected to the terminal 8. , Terminal 8 and the chip capacitor 9 holder 10 is fixed is connected, it is insert molded into the body portion 5 during resin molding of the body portion 5.

  As a result, the chip capacitor 9 is subjected to a molding pressure during insert molding, but is supported by the holder 10, so that mechanical damage to the chip capacitor 9 due to this molding pressure can be prevented.

(Modification)
FIG. 10 is a cross-sectional view showing a modification of the detection unit 7 shown in FIG.

  FIG. 11 is an enlarged view of the XI portion in FIG.

  In this modification, as shown in FIGS. 10 and 11, instead of the capacitor support portion 11 that supports the chip capacitor 9, an adhesive portion 14 is interposed in the gap between the chip capacitor 9 and the holder 10, so that the chip capacitor 9 and the holder 10 are brought into intimate contact with each other through the bonding portion 14.

  Specifically, as described above, after the lead 71 of the Hall IC 70 is electrically connected to the terminal 8, the holder 10 is fixed to the terminal 8. Thereafter, an epoxy resin or the like is applied to the holder 10 from the right side in FIGS. 10 and 11, and the chip capacitor 9 is fixed to the holder 10 so that the adhesive portion 14 is interposed between the chip capacitor 9 and the holder 10. Thereby, the adhesion part 14 can be interposed in the gap between the chip capacitor 9 and the holder 10, and the chip capacitor 9 and the holder 10 can be brought into close contact with each other via the adhesion part 14.

  Thereafter, the chip capacitor 9 is soldered and fixed to the terminals 81-83 with the mounting seat 85 (FIGS. 5, 6, and 11). Thereby, since the chip capacitor 9 is supported by the holder 10 via the adhesive portion 14, mechanical damage to the chip capacitor 9 due to external force can be prevented.

  Thereafter, an epoxy resin or the like is applied from the right side in FIGS. 10 and 11 and solidified to form the protective resin portion 91. In this way, the detection unit 7 shown in FIG. 10 is formed. Thereafter, the detection unit 7 is insert-molded into the main body 5 when the main body 5 is molded to form the main body 5 shown in FIG.

  Thereby, the chip capacitor 9 receives a molding pressure at the time of insert molding, but since it is supported by the holder 10 via the adhesive portion 14, mechanical damage to the chip capacitor 9 due to this molding pressure can be prevented.

  Further, the bonding portion 14 is also interposed in the gap between the chip capacitor 9 and the terminal 8 to bring the chip capacitor 9 and the terminal 8 into close contact via the bonding portion 14. Thereby, since the chip capacitor 9 is supported also by the terminal 8 via the bonding portion 14, mechanical damage to the chip capacitor 9 due to external force can be more reliably prevented.

  Further, the chip capacitor 9 is likely to have a gap between the terminal 8 and the holder 10 due to the fact that electrodes are formed at both ends, and when an external force is applied to the chip capacitor 9 in a state where this gap is generated. Mechanical damage can occur. However, in the present modification, the adhesive portion 14 is configured to be interposed in the gap, so that mechanical damage due to the gap can be reliably prevented.

  Further, without removing the capacitor support portion 11, it is possible to bring the chip capacitor 9 and the holder 10 into close contact with each other via the adhesive portion 14 with the adhesive portion 14 interposed in the gap between the chip capacitor 9 and the holder 10. In this case, even if a gap between the capacitor support portion 11 and the chip capacitor 9 is generated, in the present modification, the adhesive portion 14 is configured to be interposed in the gap, so that mechanical damage due to the gap is more reliably prevented. Can be prevented.

  In this modification, the mechanical damage to the chip capacitor 9 is surely prevented not only by the external force due to the molding pressure but also by the external force due to the vibration of the host vehicle and the external force due to other causes. Can do.

  FIG. 12 is a diagram showing a modification of the terminal 8 shown in FIG.

  13 is a cross-sectional view taken along line XIII-XIII in FIG.

  In this modification, as shown in FIGS. 12 and 13, a terminal 81 that is a first terminal to which one end of the chip capacitor 9 is connected and a terminal 82 that is a second terminal to which the other end of the chip capacitor 9 is connected. Are arranged close to each other on substantially the same plane (on the plane in the left-right direction in FIG. 13) so as to be substantially parallel in the vertical direction in FIG.

  Thereby, in the terminal 8, it can be made unnecessary to form the attachment seat 85 so as to extend in the vertical direction in the figure as shown in FIG. That is, a special structure is not required for the terminal 8, and the mounting seat 85 can be provided as a part of the main body of the terminal 8.

  As a result, it is easy to provide the mounting seat 85 of the terminal 81 and the mounting seat 85 of the terminal 82 on substantially the same plane, and the gap between the chip capacitor 9 and the terminals 81 and 82 can be reduced. For this reason, the chip capacitor 9 is more reliably supported by the terminals 81 and 82. That is, mechanical damage to the chip capacitor 9 due to external force can be prevented more reliably.

  Similarly, the mounting seat 85 of the terminal 82 and the mounting seat 85 of the terminal 83 can be easily provided on substantially the same plane, and the mechanical damage to the chip capacitor 9 due to external force can be more reliably prevented.

  FIG. 14 is a circuit configuration diagram showing a modification of the fuel level gauge 1 shown in FIG.

  In this modification, as shown in FIG. 14, a two-terminal type Hall IC 70a is used instead of the three-terminal type Hall IC 70 shown in FIG. The Hall IC 70 a includes two terminals of a common lead 71 a that shares the signal lead 71 and the ground lead 72, and a power supply lead 73. The terminal 8 includes a common terminal 81 a that shares the signal terminal 81 and the ground terminal 82, an adjustment terminal 82 a, and a power supply terminal 83.

  The adjustment terminal 82a is an adjustment terminal for adjusting the output of the Hall IC 70a with respect to the level of the liquid level A1 of the fuel A, and is not connected to the control device 21 in FIG. In the above-described three-terminal type Hall IC 70, the signal terminal 81 is used as an adjustment terminal for adjusting the output of the Hall IC 70.

  As shown in FIG. 14, the fuel level gauge 1 shown in FIG. 14 includes a chip capacitor 9 that electrically protects the Hall IC 70a and a chip register 9a that is a chip element. The chip resistor 9a is a resistor that prevents an overcurrent from flowing into the Hall IC 70a from the power supply terminal 83, and has a resistance value of, for example, 30 ohms.

  By adopting the above-described configuration, the same effect as the above-described chip capacitor 9 can be obtained also in the chip register 9a.

  As described above, the fuel level gauge 1 which is the liquid level detection device according to the present invention includes the main body 5, the float 2 floating on the liquid level, the rotating part 4 rotatable with respect to the main body 5, the float 2 and the rotating part. 4, the arm 3 that converts the vertical motion of the float 2 into the rotational motion of the rotating portion 4, the magnet 6 built in the rotating portion 4, and the magnetic flux density of the magnet 6 built in the main body portion 5 is measured. Accordingly, the Hall IC 70 which is a magnetoelectric conversion element for detecting the rotation angle of the rotating portion 4 with respect to the main body 5, the terminal 8 which electrically connects the Hall IC 70 to the outside, and the Hall IC 70 which is electrically connected to the terminal 8, Chip capacitor 9 and chip register 9a which are chip elements for electrically protecting 70a, and chip capacitor 9 and chip register fixed to terminal 8 and connected to terminal 8 A holder 10 that supports the chip 9a, and a bonding portion 14 that is placed in the gap between the chip capacitor 9 or chip resistor 9a connected to the terminal 8 and the holder 10 to bring the chip capacitor 9 or chip register 9a and the holder 10 into close contact with each other. The chip capacitor 9 and the chip resistor 9 a connected to the terminal 8 are supported by the holder 10 fixed to the terminal 8 via the bonding portion 14.

  Thereby, the liquid level detection apparatus which can prevent the mechanical damage of a chip element can be provided.

  In the above example, the holder 10 is fixed to the terminal 8 by heat caulking or press-fitting. However, the present invention is not limited to this, and the holder 10 is formed by being fixedly attached to a part of the terminal 8 by molding. It can be set as the structure to do. Thereby, since formation of the holder 10 and fixation to the terminal 8 are simultaneously performed by so-called outsert molding, the above-described effects can be obtained more easily.

  Next, a fuel level gauge 1 according to another modification of the embodiment of the present invention described above will be described.

  FIG. 15 is a sectional view of a fuel level gauge 1 according to another modification of the embodiment of the present invention. FIG. 15 corresponds to a sectional view taken along line VI-VI in FIG.

The fuel level gauge 1 according to another modification of the embodiment of the present invention is different from the fuel level gauge 1 according to the embodiment of the present invention in the configuration of the detection unit 7, mainly the fixing method of the terminal 8 and the holder 10. Is different. That is, the holder 10 when molding a resin material, the terminal 81, 82, 83, the insert formed to shape and held within the mold, thereby integrally fixing the terminal 81, 82, 83 and the holder 10 It has become.

  Hereinafter, the configuration of the fuel level gauge 1 according to another modification of the embodiment of the present invention will be described focusing on differences from the fuel level gauge 1 according to the embodiment of the present invention.

When the terminal 81, 82, 83 and the holder 10 are integrally fixed by insert forming type, the holder 10, as shown in FIG. 15, a portion of the terminal 81, 82 and 83 (terminal 83 is not shown) Are fixed so as to cover both front and back surfaces (left and right surfaces in FIG. 15).

The holder 10 is provided with a recess 15 so as to expose the surface (the right side surface in FIG. 15) of the terminals 81, 82, 83 (the terminal 83 is not shown). As shown in FIG. 15, the chip capacitor 9 as a chip element is accommodated in the recess 15 and electrically connected to the terminals 81 and 82 by soldering. As shown in FIG. 15, an adhesive 16 is filled between the back surface, which is the surface of the chip capacitor 9 on the terminal 8 side, and the surface of the holder 10 facing the back surface. The adhesive 16 layer is formed by first temporarily fixing in the recess 15 of the holder 10 via the chip capacitor 9 adhesive 16 and then soldering the chip capacitor 9 to the terminals 81 and 82. The adhesive 16 temporarily fixes and holds the chip capacitor 9 before soldering, and prevents a gap space (air layer) from being formed between the terminal 8 side of the chip capacitor 9 and the holder 10. If there is a gap space (air layer) between the terminal 8 side of the chip capacitor 9 and the holder 10, the chip capacitor 9 is only indicated to the terminals 81 and 82 at both ends thereof. Therefore, the detection unit 7 in the step of insert forming the shape in the main body 5, a chip capacitor 9 bending stress is generated in the chip capacitor 9 when the injection resin pressure is applied to the chip capacitor 9 may be damaged. By filling this gap space with the adhesive 16 in advance, bending stress is not generated in the chip capacitor 9 when the injection resin pressure is applied to the chip capacitor 9, and damage to the chip capacitor 9 can be prevented.

  In the recess 15, a chip register 9 a (not shown), which is a chip element, is also soldered and fixed to a terminal 82 and a terminal 83 (not shown) by a method similar to that for the chip capacitor 9. .

As shown in FIG. 15, the holder 10 is provided with a mold support portion 12 that is a convex portion. The mold support 12 is formed to oppose each of the chip capacitor 9 and the chip register 9a (not shown). That is, in this case, two mold support portions 12 are formed. However, the mold support portion 12 does not necessarily have to be provided independently for each chip element as described above, and may be a single shape in which two mold support portions 12 are connected. Mold support 12, the detection unit 7, when the insert formed shape to the inner body portion 5 in contact with the mold for molding the body portion 5. Thereby, when the chip capacitor 9 and the chip register 9a receive the pressure of the injected resin, the movement of the terminal 8 is prevented, so that the chip capacitor 9 is stably supported on the flat plate. Therefore, since the stress generated in the chip capacitor 9 and the chip register 9a can be made uniform and no stress concentration portion can be generated, the chip capacitor 9 and the chip register 9a can be prevented from being damaged.

The recess 15 is filled with a resin material after the chip capacitor 9 and the chip register 9a are soldered, and a protective resin portion 91 is formed as shown in FIG. Protective resin portion 91, hole IC70 in the terminal 8, the chip capacitor 9, the chip register 9a the detection unit 7 (not shown) is electrically connected, the pressure of the injected resin during the insert formed shape to the inner body portion 5 In order to protect the chip capacitor 9 and the chip resistor 9a from heat. In another modification, the protective resin portion 91 can be prevented from flowing out of the concave portion 15 by the inner wall of the concave portion 15 when the protective resin portion 91 is not yet cured immediately after filling.

  In the above-described embodiment of the present invention, its modifications, and other modifications, the case where the liquid level detection device is applied to the fuel level gauge 1 for an automobile has been described as an example. It is not necessary to limit to the fuel level gauge 1 for use. The present invention can be applied to detection of a liquid level in a container such as another liquid mounted on an automobile, for example, engine cooling water. Furthermore, the present invention can be applied not only for automobiles but also for detecting a liquid level in a liquid container provided in various consumer devices.

FIG. 1 is a front view of a fuel level gauge 1 which is a liquid level detection device according to an embodiment of the present invention. 2 is a cross-sectional view taken along line II-II in FIG. 3 is a cross-sectional view taken along line III-III in FIG. FIG. 4 is a schematic diagram for explaining the magnetic flux distribution of the magnet 6 shown in FIG. FIG. 5 is a V arrow view of the terminal 8 shown in FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. FIG. 7 is a cross-sectional view of the detection unit 7. FIG. 8 is a cross-sectional view of the main body 5 shown in FIG. FIG. 9 is a circuit configuration diagram illustrating an electrical circuit configuration of the fuel level gauge 1 according to the embodiment of the present invention. FIG. 10 is a cross-sectional view showing a modification of the detection unit 7 shown in FIG. FIG. 11 is an enlarged view of the XI portion in FIG. FIG. 12 is a diagram showing a modification of the terminal 8 shown in FIG. 13 is a cross-sectional view taken along line XIII-XIII in FIG. FIG. 14 is a circuit configuration diagram showing a modification of the fuel level gauge 1 shown in FIG. It is sectional drawing of the fuel level gauge 1 by the other modification of one Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fuel level gauge (liquid level detection apparatus), 2 float, 3 arm 4 rotation part, 41 hole part, 42 holding part, 42a insertion port, 43 through-hole 5 main-body part, 51 axial part, 52 groove | channel, 53 retaining ring, 6 Magnet 7 Detection unit, 70 Hall IC (Hall integrated circuit, magnetoelectric transducer)
71 Signal lead, 71a Common lead, 72 Ground lead, 73 Power lead 8 Terminal (1st terminal, 2nd terminal)
81 Signal terminal (1st terminal, 2nd terminal)
81a Shared terminal (Terminal 1 and Terminal 2)
82 Grounding terminal (1st terminal, 2nd terminal)
82a Adjustment terminal (1st terminal, 2nd terminal)
83 Power terminal (Terminal 1 and Terminal 2)
84 Fixing hole, 85 Mounting seat 9 Chip capacitor (chip element), 9a Chip register (chip element)
91 protective resin part, 92 solder part 10 holder, 11 capacitor support part (element support part), 12 type support part (convex part)
DESCRIPTION OF SYMBOLS 13 Protective case part, 14 adhesion part, 15 recessed part, 16 adhesives 20 combination meter, 21 control apparatus, 22 fuel meter 23 ignition switch, 24 battery A fuel, A1 liquid level, D1 outer diameter dimension, D2 inner diameter dimension, W opening Size

Claims (7)

A resin-molded main body,
A float floating on the liquid surface;
A rotating part rotatable with respect to the main body part;
An arm for connecting the float and the rotating part to convert the vertical movement of the float into a rotational movement of the rotating part;
A magnet built in the rotating part;
A magnetoelectric conversion element that is built in the main body part and detects the rotation angle of the rotating part relative to the main body part by measuring the magnetic flux density of the magnet;
A terminal built in the main body and electrically connecting the magnetoelectric transducer to the outside;
A liquid level detection device comprising a chip element electrically connected to the terminal and electrically protecting the magnetoelectric conversion element,
It said terminal is fixed to the holder which is a resin molded covers both the front and back surfaces in part of the terminal,
Before SL holder comprising a concave portion formed so as to expose the surface of the terminal,
The chip element is housed in the recess and electrically connected to the terminal in the recess;
The terminal insert by a molding secured within said holder and said chip elements are connected is insert molded into the body portion,
The holder includes a convex portion at a position opposite to the side where the concave portion is formed and facing the chip element,
The surface of the tip of the convex portion is substantially flush with the surface of the main body . The liquid level detection device according to claim 1 , wherein an adhesive is filled between a back surface which is a surface of the chip element on the terminal side and a surface of the holder facing the back surface. The liquid level detection device according to claim 1, wherein the concave portion is filled with a resin material . A protective resin portion that is formed of a resin material filled in the concave portion and covers a surface of the chip element that is not supported by the holder and a connection portion of the chip element to the terminal is provided. Item 4. The liquid level detection device according to Item 3 . It said chip element, the liquid level detecting apparatus according to any one of claims 1 to 4, characterized in that at least one of the chip capacitors and chip registers. The holder, a liquid level detecting apparatus according to any one of claims 1 to 5, characterized and Turkey a protective case portion covering and protecting the magnetoelectric converting element which is connected to the terminal . A method of manufacturing a liquid level detection device according to any one of claims 1 to 6,
A first forming shapes step of fixing in the holder the terminal by insert forming type upon molding by the holder resin material,
A connecting step of electrically connecting said chip elements are arranged in the recess of the holder and the terminal after the first forming shape step,
Said body portion when molding a resin material, and a second forming shape steps you insert molding the holder terminated the connection step in said body portion,
Wherein in the second forming shape step, the holder manufacturing method of the liquid level detecting apparatus characterized by being retained by contact with the protrusion on the mold into the mold cavity of the main body portion.

Images