JP5494091B2 - Manufacturing method of liquid level detection device - Google Patents

Description

  The present invention relates to a method for manufacturing a liquid level detection device for detecting the height of a liquid level stored in a container.

  Conventionally, a liquid stored in a container using a housing fixed to a container for storing liquid and a stator that is rotatably supported by the housing and relatively rotates following the liquid level of the liquid stored in the container. There has been known a liquid level detection device for detecting the height of the liquid level.

  As one type of such a liquid level detection device, for example, the liquid level sensor disclosed in Patent Document 1 includes a detection element that detects the angle of the stator, electronic components such as a capacitor and a resistor, a terminal, and the like. The circuit unit further accommodated in the housing is further provided. An electronic component used in the liquid level sensor has a main body portion and a lead wire for connection protruding from the main body portion. This electronic component is soldered to the terminal in a state where a lead wire is inserted into a concave groove provided in the terminal and the terminal is positioned in the plate surface direction. As described above, the positioning in the direction of the plate surface of the terminal is performed by the concave groove, thereby improving the reliability of connection between the electronic component and the terminal.

  On the other hand, for example, the liquid level sensor disclosed in Patent Document 2 includes a circuit unit having a detection element, an electronic component, a terminal, and the like, similar to that disclosed in Patent Document 1. In the liquid level sensor disclosed in Patent Document 2, the circuit unit is protected from the liquid stored in the container by being embedded in the housing.

  In order to manufacture a housing as disclosed in Patent Document 2, first, a detection element and an electronic component are connected to a terminal. Then, a terminal to which the detection element and the electronic component are connected is placed in a cavity in the mold, and the cavity is filled with a molding material for the housing. As described above, the housing in which the circuit portion is embedded can be manufactured.

JP 2004-152886 A Japanese Patent No. 4138527

  Now, when manufacturing the housing used for the liquid level detection apparatus of patent document 2, the molding material of a housing is filled in the said metal mold | die. Then, a part of the molding material of the housing flows toward the electronic component in order to cover the electronic component connected to the terminal. This molding material makes a resistance force act on the electronic component by contacting the electronic component. Therefore, these connections must be ensured so that the connection between the electronic component and the terminal is not peeled off due to the resistance of the molding material.

  Therefore, it is conceivable to improve the reliability of the connection by connecting the electronic component to the terminal in a state where the groove is positioned as in the liquid level sensor disclosed in Patent Document 1. However, in the configuration disclosed in Patent Document 1, even if the position of the electronic component in the plate surface direction of the terminal can be defined by the side surface in the plate thickness direction of the groove, it is in the plate thickness direction of the terminal and the axial direction of the lead wire. The position of the electronic component in cannot be defined.

  As described above, the electronic component may be connected to the terminal while causing a shift in the axial direction of the lead wire. Then, the connection between the lead wire and the terminal tends to be uncertain. Therefore, when the electronic component is covered with the molding material of the housing, the terminal and the lead may be disconnected due to the resistance force acting on the electronic component due to the flow of the molding material. According to the poor connection that occurs in this way, the electronic component cannot perform its original function, and the detection of the stator angle by the detection element is hindered.

  The present invention has been made in view of the above problems, and an object thereof is to provide a method for manufacturing a liquid level detection device capable of maintaining high detection accuracy by causing an electronic component to exhibit these two functions. It is to be.

  In order to achieve the above object, according to the first aspect of the present invention, a fixed body fixed to a container for storing liquid, and a liquid that is rotatably supported by the fixed body and follows the liquid level stored in the container. A rotating body that relatively rotates, a terminal provided with a detecting element connecting portion and an electronic component connecting portion, a detecting element that is connected to the detecting element connecting portion and detects an angle of the rotating body, and an electron projecting from the main body portion and the main body portion And a circuit part embedded in the interior of the fixed body, and a method of manufacturing a liquid level detection device for detecting the height of the liquid level The terminal is placed in the cavity in the first mold, and the cavity is filled with the molding material of the fixed body. With one closed end closed A first forming step for forming a covering portion that covers the terminal, and a positioning portion that is an open end whose other end in the longitudinal direction is open, and after the first forming step, from the open end toward the closed end With the electronic component positioned by inserting the leg into the positioning groove, the connecting step of connecting the leg to the electronic component connecting portion, and the result of the connecting step are installed in the cavity in the second mold, And a second molding step of covering the electronic component and molding the appearance of the stationary body by filling the cavity with the molding material of the stationary body.

  According to the present invention, in the first molding step, the longitudinal positioning groove in which the electronic component connecting portion is exposed is formed at the bottom portion by the molding material of the fixed body. Of the longitudinal ends of the positioning groove, one end is a closed end and the other end is an open end. According to the shape of the positioning groove, the leg portion of the electronic component can be inserted into the positioning groove from the open end in the connection step. And the position in the longitudinal direction of the positioning groove | channel can be prescribed | regulated for an electronic component by the inserted leg part striking against a closed end. Further, the leg portion is restricted from moving in the width direction of the positioning groove in the direction intersecting the longitudinal direction of the positioning groove by the side wall surface of the positioning groove extending along the longitudinal direction. Therefore, the electronic component in which the leg portion is inserted into the positioning groove can define the position of the positioning groove in the width direction.

  According to the above, the leg part of the electronic component is connected to the electronic component connection part of the terminal at the correct position in the connection process. Therefore, the connection between the electronic component and the terminal can be reliable. Therefore, when the electronic component is covered in the second molding step, the connection between the electronic component connecting portion and the leg portion is not caused due to the electronic component being pushed by the flow of the molding material of the fixed body. Can be prevented. Thereby, even if it is an electronic component embed | buried under a fixed body, an original function can be exhibited and the detection of the angle of the rotary body by a detection element is not prevented. Therefore, the liquid level detection device manufactured by the manufacturing method according to claim 1 can maintain high detection accuracy.

  In the invention according to claim 2, the dimension in the depth direction of the positioning groove formed in the first molding step is larger than the dimension of the cross section of the leg in the direction intersecting the protruding direction of the leg. And

  According to this invention, since the dimension in the depth direction of the positioning groove is larger than the dimension of the cross section of the leg in the direction intersecting the protruding direction, the entire leg can be accommodated in the positioning groove. Therefore, when positioning the electronic component in the connection process, the leg portion is difficult to be detached from the positioning groove. As described above, the action of the positioning groove that can accurately define the connection position of the electronic component is reliably exhibited, and the occurrence of poor connection between the electronic component connection portion and the leg portion can be reliably suppressed. Therefore, a liquid level detecting device that realizes the function of the electronic component and maintains high detection accuracy is realized.

  In the invention according to claim 3, in the connection step, by applying a current between the leg portion and the electronic component connecting portion through the electrode in a state where the leg portion is pressed toward the electronic component connecting portion by the electrode, An electronic component is connected to a terminal by welding.

  According to this invention, the legs of the electronic component are pressed in the depth direction of the positioning groove along with the longitudinal direction and the width direction of the positioning groove by being pressed toward the electronic component connecting portion by the electrode used for welding. Is also positioned. Therefore, since the leg part of the electronic component is connected to the electronic component connection part of the terminal at a more accurate position, the leg part of the electronic component is securely connected to the electronic component connection part and is difficult to peel off from the terminal. Therefore, a liquid level detecting device that realizes the function of the electronic component and maintains high detection accuracy is realized.

  In the invention according to claim 4, in the first forming step, by enlarging a part of the positioning groove in the width direction, the covering portion provided with the welding electrode hole having a shape corresponding to the shape of the electrode is formed, In the connecting step, the electrode is inserted into the welding electrode hole, and the leg is pressed toward the electronic component connecting portion by the electrode.

  According to this invention, according to the shape of the electrode used in the connection step and by expanding a part of the positioning groove in the width direction, the shape of the electrode is not limited to the dimension in the width direction of the positioning groove. . Therefore, in a connection process, the electrode provided with the pressing area which can press a leg part toward an electronic component connection part reliably can be inserted in a welding electrode hole, and a leg part can be pressed toward an electronic component connection part. As a result, it is possible to suppress the occurrence of welding defects in the connection process, so that the connection with the electronic components of the terminal is further ensured. Therefore, a liquid level detecting device that realizes the function of the electronic component and maintains high detection accuracy is realized.

  In the invention according to claim 5, the terminal is plate-shaped, and in the first molding step, the counter electrode hole exposing the electronic component connecting portion at the bottom is opposed to the welding electrode hole in the plate thickness direction of the terminal. Forming the covering part, in the connection process, insert the electrode into each of the welding electrode hole and the counter electrode hole, and connect the leg part to the electronic part with the pair of electrodes sandwiching the leg part and the electronic part connection part. It welds to a part, It is characterized by the above-mentioned.

  In the present invention, a counter electrode hole that exposes the electronic component connecting portion is provided at the bottom so as to face the welding electrode hole in the thickness direction in the covering portion that covers the terminal. And a leg part of an electronic component and the electronic component connection part of a terminal can be clamped by inserting a pair of electrode in a counter electrode hole and a welding electrode hole. As described above, since the leg portion is welded in a state of being reliably pressed toward the electronic component connection portion, the leg portion is reliably connected to the electronic component connection portion. As described above, according to the fact that it is possible to suppress the occurrence of poor welding between the leg portion and the electronic component connecting portion, a liquid level detecting device that exhibits the function of the electronic component and maintains high detection accuracy is realized.

  In the invention according to claim 6, the second mold is provided with a gate for filling the cavity with the molding material of the fixed body, and in the second molding step, there is a positioning groove between the gate and the electronic component. The result is placed in the cavity in a positioned state.

  In the second molding step according to the present invention, in the cavity where the result of the connection step is installed, the electronic component connected to the result and the cavity in the second mold are filled with the molding material of the fixed body. A positioning groove is located between the gate and the gate. Therefore, the molding material filled into the cavity through the gate is prevented from flowing toward the electronic component by the portion where the positioning groove is formed in the covering portion, and the flow rate is reduced. As described above, when the molding material covers the electronic component, it is possible to reduce the resistance force that acts on the electronic component from the molding material.

  As described above, the covering portion having the positioning groove has the effect of improving the reliability of the connection by accurately positioning the electronic component and synergistically exhibits the effect of reducing the resistance force that causes the connection failure. Thus, poor connection between the electronic component and the terminal is surely reduced. Therefore, a liquid level detection device that maintains high detection accuracy is realized.

  Further, as in the invention described in claim 7, the cavity is filled also by forming a covering portion having a peripheral wall portion surrounding the electronic component to be connected in the connecting step in the first forming step. The flow of the molding material toward the electronic component can be prevented. Therefore, the peripheral wall portion in which the positioning groove is provided can exhibit a synergistic effect of improving the connection reliability and reducing the resistance force that causes the connection failure. Therefore, a liquid level detecting device that realizes the function of the electronic component and maintains high detection accuracy is realized.

  In the invention according to claim 8, in the first molding step, the covering portion that covers the terminal in a state where the detection element connection portion is exposed is formed, and in the connection step, the detection element is connected to the detection element connection portion, In the second molding step, the detection element is covered together with the electronic component.

  In the invention according to claim 9, in the first molding step, a covering portion that covers the detection element together with the terminal is installed in the cavity in the first mold with the detection element connected to the detection element connection portion. Is formed.

  Like these inventions, the connection of the detection element to the detection element connection portion may be made in the connection step, or may be made before the first molding step. When the detection element is connected to the detection element connection portion in the connection process, the detection element is covered with the molding material of the fixed body in the second molding process. Moreover, when a detection element is connected to a detection element connection part before a 1st shaping | molding process, the said detection element is coat | covered with the molding material of a fixed body in a 1st shaping | molding process.

It is a front view which shows the fuel level gauge manufactured by the manufacturing method by 1st embodiment of this invention. It is the II-II sectional view taken on the line of FIG. It is a figure for demonstrating the characteristic part of a housing, Comprising: It is the III arrow directional view of FIG. It is a figure for demonstrating the characteristic part of a housing, Comprising: It is a figure which shows the structure on the opposite side to FIG. It is the VV sectional view taken on the line of FIG. It is a figure for demonstrating in detail the manufacturing method of the fuel level gauge by 1st embodiment of this invention. It is a figure which shows the modification of FIG.

  Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings. In addition, the overlapping description is abbreviate | omitted by attaching | subjecting the same code | symbol to the corresponding component in each embodiment.

(First embodiment)
Hereinafter, the liquid level detection device according to the first embodiment of the present invention is installed in the fuel tank 90 of the vehicle, detects the height of the liquid level 91a of the fuel 91 stored in the fuel tank 90, and the combination. An example applied to a fuel level gauge that outputs detection results toward a meter (not shown) or the like will be described.

  1 and 2 are a front view and a cross-sectional view taken along line II-II of the fuel level gauge 100 according to the first embodiment of the present invention, and shows a state in which the fuel level gauge 100 is fixed in a fuel tank 90 that is a container. Show. The fuel level gauge 100 is attached to the wall surface of the fuel pump module 93 installed in the fuel tank 90, and is integrally fixed to the fuel tank 90 via the fuel pump module 93. Here, the method of attaching the fuel level gauge 100 to the fuel tink is not limited to the above-described form, and it may be directly fixed inside the fuel tank 90 via a stay or the like (not shown). Good.

(Basic configuration)
First, the basic configuration of the fuel level gauge 100 will be described with reference to FIGS. 1 and 2. The fuel level gauge 100 is formed by combining a float 60, a float arm 50, a magnet holder 30, a housing 20, a circuit unit 40, a wiring 70, and the like.

  The float 60 is made of a material having a small specific gravity such as foamed ebonite. The float 60 is formed from a material having a specific gravity smaller than that of the fuel 91 that is a liquid, so that the float 60 can float on the liquid surface 91 a of the fuel 91. The float 60 has a thin rectangular parallelepiped shape so that the height of the liquid level 91a can be detected even when the remaining amount of the fuel 91 is very small. Further, a through hole 61 is formed in the float 60 so as to pass through the center of gravity of the float 60. The float 60 is not limited to the rectangular parallelepiped shape described above, and may be a columnar shape or the like.

  The float arm 50 is formed of a round bar-shaped core made of a metal material such as stainless steel. Of the both ends of the float arm 50, the float holding portion 53 is formed at the end on the float 60 side by bending the float arm 50 about 90 degrees in the same direction as the rotation axis of the magnet holder 30. . The float arm 50 holds the float 60 by inserting the float holding portion 53 into the through hole 61 of the float 60. At the end of the float arm 50 on the magnet holder 30 side, a stopper 51 is formed by bending the float arm 50 in the same direction as the rotation axis of the magnet holder 30 and about 90 degrees toward the housing 20.

  The magnet holder 30 is formed in a cylindrical shape with, for example, polyacetal (POM) resin, which has good oil resistance and solvent resistance and excellent mechanical properties. The magnet holder 30 includes a bearing portion 33, a magnet 31, a flange portion 34 having a stopper hole 35, and a float arm fixing portion 32. The magnet holder 30 is rotatably supported by the housing 20 by a bearing portion 33 formed on the inner peripheral surface thereof.

  The magnet 31 is a cylindrical member exhibiting ferromagnetism, and is embedded in the magnet holder 30 by insert molding. The magnet 31 is embedded so that the central axis thereof coincides with the central axis of the magnet holder 30, and rotates integrally with the magnet holder 30. As the magnet 31, for example, a permanent magnet such as a ferrite magnet, a rare earth magnet, an alnico magnet, or a bonded magnet is used.

  The flange portion 34 is provided on the outer peripheral surface of the magnet holder 30 and includes a stopper hole 35. The float arm 50 is fixed to the float arm fixing portion 32 in a state where the stopper portion 51 is inserted through the stopper hole 35.

  With the above-described configuration, the reciprocating motion of the float 60 that moves up and down following the liquid level 91a of the fuel 91 by the float arm 50 supported at one end by the magnet holder 30 is converted into a rotational motion, and the float arm 50 and the magnet holder 30 are transmitted to an integral element. Therefore, the magnet holder 30 follows the liquid level of the fuel 91 stored in the fuel tank 90 and rotates relative to the housing 20.

  The housing 20 is formed into a rectangular plate shape using polyphenylene sulfide (PPS) resin or the like that is not affected by an organic solvent such as the fuel 91 and does not decrease in strength even at high temperatures. The housing 20 is attached to the wall surface of the fuel pump module 93 with its longitudinal direction oriented in the vertical direction, and fixes the fuel level gauge 100 to the fuel tank 90. The housing 20 includes a shaft portion 21 and stopper walls 24a and 24b.

  The shaft portion 21 is a cylindrical convex portion that is formed in the vicinity of the center portion of the housing 20 and protrudes in the plate thickness direction of the housing 20. The magnet holder 30 is rotatably supported on the housing 20 by fitting the bearing portion 33 of the magnet holder 30 onto the shaft portion 21. In addition, when the outer diameter of the shaft portion 21 is slightly smaller than the inner diameter of the bearing portion 33, the magnet holder 30 can rotate smoothly with respect to the housing 20.

  The stopper walls 24 a and 24 b are provided on two wall portions facing each other in the horizontal direction in a state where the stopper walls 24 a and 24 b are attached to the wall surface of the fuel pump module 93. These stopper walls 24 a and 24 b are disposed at positions on the rotation path of the stopper portion 51 so as to come into contact with the stopper portion 51 of the float arm 50. One stopper wall 24a is for preventing the float 60 from coming into contact with the bottom surface 90b of the fuel tank 90. In the state where the remaining amount of the fuel 91 in the fuel tank 90 is very small (solid line in FIG. 1). The stopper portion 51 is provided in contact with the stopper portion 51. The other stopper wall 24b is for preventing the float 60 from contacting the ceiling surface 90a of the fuel tank 90, and the fuel tank 90 is filled with the maximum amount of fuel 91 (see FIG. 1). In the two-dot chain line), it is provided so as to come into contact with the stopper portion 51.

  The circuit unit 40 includes a magnetoelectric conversion element 42, terminals 41 a, 41 b, 41 c, and a capacitor 44, and detects the rotation angle of the magnet holder 30.

  The magnetoelectric conversion element 42 is embedded in the shaft portion 21 of the housing 20 so as to be positioned on the inner peripheral side of the magnet 31 disposed in the magnet holder 30. The magnetoelectric conversion element 42 includes three input / output units 42a serving as an input terminal, a ground terminal, and an output terminal. The three input / output units 42a are connected to terminals 41a, 41b, and 41c, respectively (see FIG. 4). The magnetoelectric conversion element 42 is a Hall element and receives a magnetic field action from the outside in a state where a voltage is applied, thereby detecting a voltage proportional to the density of magnetic flux passing through the magnetoelectric conversion element 42 as a detection result. Output from the output terminal.

  The terminals 41a, 41b, and 41c are made of a highly conductive phosphor bronze plate, brass plate, or the like, and are embedded in the housing 20 in parallel in the horizontal direction of the housing 20 (see FIG. 4). Each terminal 41a, 41b, 41c has a plate shape extending along the vertical direction of the housing 20. Of the three terminals 41a, 41b and 41c, the terminal closest to the stopper wall 24a is referred to as a terminal 41a, and the terminal closest to the stopper wall 24b is referred to as a terminal 41c. Further, a central one sandwiched between the terminal 41a and the terminal 41c is referred to as a terminal 41b. The three terminals 41a to 41c are electrically connected to the input / output units 42a of the magnetoelectric transducer 42 at the ends on the lower side in the vertical direction among the ends in the extending direction. Further, of the both end portions of the embedded terminals 41 a to 41 c, the end portion on the upper side in the vertical direction protrudes to the outside of the housing 20.

  The capacitor 44 is a passive element that can store and discharge an amount of electric charge according to a predetermined capacitance, and removes noise generated or input to the circuit unit 40. The capacitor 44 has a plate-like main body 44a and two legs 44b. The two leg portions 44b are wire rods made of a metal material, and project from the side surface of the main body portion 44a along the plate surface direction of the main body portion 44a. The capacitor 44 is connected to the terminals 41a to 41c by welding the ends of the leg portions 44b in the extending direction to the terminals 41a to 41c. In the first embodiment, the circuit unit 40 is provided with two capacitors 44. One capacitor 44 has one leg 44b connected to the terminal 41b and the other leg 44b connected to the terminal 41a. The other capacitor 44 has one leg 44b connected to the terminal 41b and the other leg 44b connected to the terminal 41c.

  Here, in the terminals 41a to 41c, a portion to which the input / output unit 42a of the magnetoelectric conversion element 42 is connected is referred to as a detection element connection unit 40a. In addition, in the terminals 41a to 41c, a portion to which the leg portion 44b of the capacitor 44 is connected is referred to as a capacitor connection portion 40b.

  Three wirings 70 are provided, and are connected to the terminal terminals 41a to 41c, respectively. The detection result of the rotation angle of the magnet holder 30 by the magnetoelectric conversion element 42 is transmitted to a measuring device such as a combination meter outside the fuel tank 90 via these wires 70. These wirings 70 each have a terminal portion 72 and a lead wire 73. The terminal portion 72 is formed of a highly conductive phosphor bronze plate or brass plate or the like, and is securely electrically connected to the terminals 41a to 41c by caulking or fusing (heat caulking) or the like. . The lead wire 73 is a lead wire formed by coating the outer surface of a highly conductive metal wire with an insulator such as rubber.

  According to the above, one terminal 41a can be electrically connected to a battery (not shown) via the connected wiring 70 and the like, and a battery voltage can be applied to the input / output unit 42a as the input terminal of the magnetoelectric transducer 42. It has become. The other terminal 41 b is grounded via the connected wiring 70 and the like, and can provide a ground voltage to the input / output unit 42 a as a ground terminal of the magnetoelectric conversion element 42. Further, another terminal 41c is connected to an external measuring device such as a combination meter via the connected wiring 70 and the like, and can output a detection result from an input / output unit 42a as an output terminal of the magnetoelectric conversion element 42. It has become.

  With the configuration described so far, the fuel level gauge 100 outputs a voltage corresponding to the level of the liquid level 91 a of the fuel 91. Specifically, when the magnetic lines of force of the magnet 31 that rotates and displaces integrally with the magnet holder 30 are orthogonal to the longitudinal direction of the magnetoelectric conversion element 42, the magnetic flux density that passes through the magnetoelectric conversion element 42 is maximized. Thereby, the voltage as the detection result output by the magnetoelectric conversion element 42 is maximized. When the magnet 31 rotates in a specific direction due to the change in the liquid level 91a and the magnetic flux density passing through the magnetoelectric conversion element 42 decreases, the voltage as the detection result output from the magnetoelectric conversion element 42 decreases. Further, when the magnet 31 rotates in a specific direction and the direction of the magnetoelectric conversion element 42 and the line of magnetic force is parallel, the magnetic flux density passing through the magnetoelectric conversion element 42 is minimized, and the detection result output from the magnetoelectric conversion element 42 As a minimum voltage.

(Production method)
Next, the manufacturing method of the fuel level gauge 100 by 1st embodiment is demonstrated in detail using FIGS. The manufacturing method of the fuel level gauge 100 includes a first molding process, a connection process, a second molding process, and an assembly process.

<First molding process>
First, in the first molding step, the terminals 41a to 41c are installed in the cavity 82 in the first mold 81 (FIG. 6A). And the coating | coated part 26 which coat | covers the terminals 41a-41c is shape | molded by fuse | melting and filling the PPS resin which is the molding material of the housing 20 in the cavity 82 in the 1st metal mold | die 81. FIG. Note that the gate for filling the melted PPS resin into the cavity 82 is omitted in FIG.

  From the covering portion 26 formed in the first forming step, the detection element connecting portion 40a and the capacitor connecting portion 40b of the terminals 41a to 41c are exposed. The covering portion 26 includes a peripheral wall portion 27 that surrounds the periphery of the component accommodating portion 28a in which the capacitor 44 is accommodated, and an element accommodating portion 28b in which the magnetoelectric conversion element 42 is accommodated. Is provided. Further, the covering portion 26 has a positioning groove 25 in the peripheral wall portion 27. The positioning groove 25 has a longitudinal shape extending from the inner peripheral side to the outer peripheral side of the peripheral wall portion 27, and forms an open end 25a and a closed end 25b, side wall surfaces 25c and 25d, and a bottom portion 25e. . The number of positioning grooves 25 formed is the same as the number of leg portions 44b of the capacitor 44 connected to the terminals 41a, 41b, 41c.

  The open end 25 a is one end in the longitudinal direction of the positioning groove 25 and is open to the inner peripheral side of the peripheral wall portion 27. The closed end 25 b is the other end in the longitudinal direction of the positioning groove 25 and is closed by the peripheral wall portion 27. The side wall surfaces 25c and 25d are wall surfaces of the positioning groove 25 extending from the open end 25a to the closed end 25b, and are opposed to each other in the width direction of the positioning groove 25. The bottom portion 25e exposes the capacitor connection portion 40b of the terminals 41a, 41b, and 41c.

  In addition, in the positioning groove 25, the dimension in the depth direction from the top surface 27 a of the peripheral wall portion 27 to the capacitor connecting portion 40 b exposed at the bottom portion 25 e is a cross section in a direction intersecting the protruding direction of the leg portion 44 b of the capacitor 44. That is, it is larger than the wire diameter of the leg portion 44b. In addition, in the first embodiment, the dimension in the depth direction of the positioning groove 25 is larger than the dimension in the thickness direction of the main body 44a of the capacitor 44.

  Furthermore, electrode holes 29 a and 29 b are provided in the covering portion 26. These electrode holes 29a and 29b are positioned so as to face each other in the plate thickness direction of the terminals 41a, 41b and 41c. The electrode hole 29a exposes, on its bottom 25e, the side surface on the side connected to the capacitor 44 among the both side surfaces in the plate thickness direction of the capacitor connection portion 40b. The electrode hole 29a is formed by enlarging a part of the center in the longitudinal direction in the positioning groove 25 in the width direction. On the other hand, the electrode hole 29b exposes, on its bottom 29c, the side surface opposite to the side to which the capacitor 44 is connected, of both side surfaces in the plate thickness direction of the capacitor connecting portion 40b.

  The number of the electrode holes 29 a and 29 b is the same as the number of leg portions 44 b of the capacitor 44. In addition, the shape of the electrode holes 29a and 29b corresponds to the shape of the electrode 89 used in the next process. Specifically, in the first embodiment, the electrode holes 29a and 29b are cylindrical holes and are similar in shape to the columnar electrode 89. In addition, the inner diameters of the electrode holes 29a and 29b are larger than the outer diameter of the electrode 89 so that the electrode 89 can be easily inserted.

<Connection process>
In the connection process after the first molding process, first, the magnetoelectric conversion element 42 is inserted into the element housing portion 28b. Then, by accommodating the magnetoelectric conversion element 42 in the element accommodating portion 28b, the input / output portion 42a and the detection element connecting portion 40a are brought into contact with each other (see FIGS. 6B and 6C).

  Next, a pair of columnar electrodes 89 is prepared, and the detection element connecting portion 40a and the input / output portion 42a are sandwiched between the pair of electrodes. In this manner, by applying a current between the electrodes 89 in a state where the detection element connection portion 40a and the input / output portion 42a are crimped between the electrodes 89, the contact portions of the detection element connection portion 40a and the input / output portion 42a with each other. Cause resistance heat. The magnetoelectric conversion element 42 is connected to the terminals 41a to 41c by welding by melting the contact portion of the detection element connection portion 40a and the input / output portion 42a with this resistance heat.

  Next, the capacitor 44 is positioned by inserting the leg portion 44b of the capacitor 44 into the positioning groove 25 from the open end 25a toward the closed end 25b. Specifically, the leg portion 44b of the capacitor 44 is inserted from the open end 25a of the positioning groove 25 along the longitudinal direction thereof. And the front-end | tip of the protrusion direction of the inserted leg part 44b collides with the closed end 25b. As a result, the capacitor 44 defines the position of the positioning groove 25 in the longitudinal direction. Further, the leg portion 44b is restricted from moving in the width direction of the positioning groove 25 by the side wall surfaces 25c and 25d. Therefore, the capacitor 44 in which the leg portion 44b is inserted into the positioning groove 25 defines the position of the positioning groove 25 in the width direction.

  Thus, the capacitor 44 is positioned in a state where the capacitor 44 is laid down with respect to the terminals 41a to 41c so that the protruding direction of the leg portion 44b protruding from the main body 44a is along the plate surface direction of the terminals 41a to 41c. . In order to more accurately position the capacitor 44 in the longitudinal direction, a jig or the like for defining the relative position of the capacitor 44 with respect to the peripheral wall 27 may be used in this connection step.

  Further, the electrode 89 is inserted into each of the electrode holes 29a and 29b. Accordingly, the pair of electrodes 89 sandwich the leg portion 44b and the capacitor connection portion 40b. In the state sandwiched between the electrodes 89, the leg portion 44b is pressed toward the capacitor connecting portion 40b. Thus, by applying a current to the leg portion 44b and the circuit portion capacitor connecting portion 40b via the electrode 89 with the leg portion 44b being pressed toward the capacitor connecting portion 40b, these elements 44b, Resistive heat is generated at the contact portions of 40b. The capacitor 44 is connected to the terminals 41a to 41c by welding by melting the contact portion between the leg portion 44b and the capacitor connection portion 40b by this resistance heat.

<Second molding step>
In the second molding step after the connecting step, first, the result 88 of the connecting step is placed in the cavity 85 in the second mold 84 (see FIG. 6D). Then, by melting and filling the cavity 85 in the second mold 84 with the PPS resin as the molding material of the housing 20 through the gate 86 provided in the second mold 84, the capacitor 44 and the magnetoelectric conversion element 42. Etc. and the appearance of the housing 20 (see FIGS. 3 and 4) is formed.

  In the second molding step, the peripheral wall 27 is located between the capacitor 44 and the gate 86 in the resultant product 88 installed in the cavity 85 in the second mold 84. Thus, by surrounding the periphery of the capacitor 44 with the peripheral wall portion 27, the molten PPS resin filled in the cavity 85 from the gate 86 is prevented from flowing toward the capacitor 44 by the peripheral wall portion 27.

<Assembly process>
In the next assembly process, the magnet holder 30 is fitted to the shaft portion 21 of the housing 20 molded by the second molding process described above. Further, the float arm 50 is attached to the magnet holder 30 and the wiring 70 is connected to the terminals 41a to 41c, thereby completing the fuel level gauge 100 (see FIGS. 1 and 2).

  According to 1st embodiment described so far, the leg part 44b of the capacitor | condenser 44 is connected with each capacitor | condenser connection part 40b of the terminals 41a-41c in a correct position in a connection process. Therefore, the connection between the capacitor 44 and the terminals 41a to 41c can be reliable. Therefore, when the co-capacitor 44 is covered in the second molding step, the connection between the capacitor connecting portion 40b and the leg portion 44b is not caused due to the capacitor 44 being pushed by the flow of the PPS resin. It can be prevented. Thereby, even if it is the capacitor | condenser 44 embed | buried under the housing 20, an original function can be exhibited and the detection of the angle of the magnet holder 30 by the magnetoelectric conversion element 42 is not prevented. Therefore, the fuel level gauge 100 manufactured by the manufacturing method of the first embodiment can maintain high detection accuracy.

  In addition, in the first embodiment, since the dimension in the depth direction of the positioning groove 25 is larger than the wire diameter of the leg part 44 b of the capacitor 44, the entire leg part 44 b can be accommodated in the positioning groove 25. Therefore, when positioning the capacitor 44 in the connection process, the leg portion 44 b is difficult to be detached from the positioning groove 25. As described above, the operation of the positioning groove 25 that can accurately define the connection position of the capacitor 44 is reliably exhibited, and the occurrence of poor connection between the capacitor connection portion 40b and the leg portion 44b can be reliably suppressed. Therefore, the fuel level gauge 100 that realizes the function of the capacitor 44 for removing noise and maintains high detection accuracy is realized.

  In addition, in the first embodiment, the leg portion 44b of the capacitor 44 that is pressed toward the capacitor connecting portion 40b by the electrode 89 used for welding in the connection step is used together with the longitudinal direction and the width direction of the positioning groove 25. The positioning groove 25 is also positioned in the depth direction. Therefore, since the leg part 44b of the capacitor | condenser 44 is connected with the circuit part capacitor | condenser connection part 40b of terminal 41a-41c in a further exact position, it becomes difficult to peel from the said terminal 41a-41c. Therefore, the fuel level gauge 100 that realizes the function of the capacitor 44 for removing noise and maintains high detection accuracy is realized.

  In addition, in the first embodiment, since the electrode groove 29a corresponding to the shape of the electrode 89 used in the connection step is formed in the positioning groove 25, the shape of the electrode 89 is the dimension in the width direction of the positioning groove 25. Not limited to. Therefore, in the connecting step, the electrode 89 having a pressing area that can reliably press the leg 44b toward the capacitor connecting portion 40b is inserted into the electrode hole 29a, and the leg 44b is pressed toward the capacitor connecting portion 40b. it can. Thereby, since generation | occurrence | production of the defect of welding in a connection process can be suppressed, the connection with the capacitor | condenser 44 of terminal 41a-41c is made still more reliably. Therefore, the fuel level gauge 100 that realizes the function of the capacitor 44 for removing noise and maintains high detection accuracy is realized.

  In addition, in the first embodiment, since the electrode hole 29b is provided in the covering portion 26 that covers the terminals 41a to 41c, the pair of electrodes 89 are inserted into the electrode holes 29a and 29b, so that the leg portion 44b and The capacitor connecting portion 40b can be held. As described above, since the leg portion 44b is welded in a state of being reliably pressed toward the capacitor connecting portion 40b, the leg portion 44b is reliably connected to the capacitor connecting portion 40b. As described above, the occurrence of poor welding between the leg portion 44b and the capacitor connecting portion 40b can suppress the fuel level gauge 100 that exhibits the function of the capacitor 44 and maintains high detection accuracy.

  In addition, in the first embodiment, the cover portion 26 molded in the first molding step is provided with the peripheral wall portion 27 surrounding the periphery of the capacitor 44 connected in the connection step, so that the PPS filled in the cavity 85 is provided. The flow of the resin toward the capacitor 44 can be prevented. Therefore, the peripheral wall portion 27 in which the positioning groove 25 is provided synergistically exhibits the action of improving the connection reliability and the action of reducing the resistance force that causes the connection failure. Therefore, the fuel level gauge 100 that realizes the function of the capacitor 44 reliably and maintains high detection accuracy is realized.

  In the first embodiment, the fuel 91 is the “liquid” according to the claims, the fuel tank 90 and the fuel pump module 93 are the “containers” according to the claims, and the housing 20 is the “fixed” according to the claims. In the body, the electrode hole 29a is in the “welding electrode hole” in the claims, the electrode hole 29b is in the “counter electrode hole” in the claims, and the magnet holder 30 is in the “rotary body” in the claims. The magnetoelectric conversion element 42 is in the “detection element” described in the claims, the capacitor connection portion 40b is in the “electronic component connection portion” in the claims, and the capacitor 44 is in the “electronic component” in the claims. The resin corresponds to the “molding material” recited in the claims, and the fuel level gauge 100 corresponds to the “liquid level detection device” recited in the claims.

(Second embodiment)
The second embodiment of the present invention shown in FIG. 7 is a modification of the first embodiment. In the manufacturing method of the fuel level gauge 100 according to the second embodiment, the magnetoelectric conversion element 42 is connected to the terminals 41a to 41c by the magnetoelectric conversion element connecting step prior to the first forming step. Hereinafter, the manufacturing method of the fuel level gauge 100 by 2nd embodiment is demonstrated in detail, referring FIGS. 3-5 based on FIG.

<Magnetic-electric conversion element connection process>
First, in the magnetoelectric conversion element connection step, the three input / output parts 42a of the magnetoelectric conversion element 42 are connected to the detection element connection parts 40a of the terminals 41a to 41c, respectively. Also in the second embodiment, as in the first embodiment, each detection element connection portion 40a and each input / output portion 42a are connected by welding to obtain a result 287 by the magnetoelectric conversion element connection step.

<First molding process>
Next, in the first molding step, the result 287 of the magnetoelectric conversion element connection step in which the magnetoelectric conversion element 42 and the terminals 41a to 41c are connected is installed in the cavity 282 in the first mold 281 (FIG. 7 ( a)). Then, the cavity 282 in the first mold 281 is melted and filled with the PPS resin that is the molding material of the housing 20, thereby covering the magnetoelectric conversion element 42 and the terminals 41a to 41c (FIG. 7B). )). The capacitor connecting portion 40b is exposed from the covering portion 226. Moreover, in 2nd embodiment, the coating | coated part 226 has the wall part 227 extended in the orthogonal direction with the longitudinal direction of terminal 41a-41c as a structure corresponded to the surrounding wall part 27 of 1st embodiment. The positioning groove 25 is formed in the wall portion 227.

<Capacitor connection process>
In the connection step after the first molding step, the capacitor 44 is positioned by inserting the leg portion 44b of the capacitor 44 into the positioning groove 25 as in the connection step of the first embodiment. Then, by inserting the electrode 89 into each of the electrode holes 29a and 29b, the leg portion 44b and the capacitor connection portion 40b are welded in a state where the leg portion 44b and the capacitor connection portion 40b are held between the electrodes 89 ( (Refer FIG.7 (c)).

<Second molding step>
In the second molding step, first, the result 288 of the capacitor connection step is placed in the cavity 285 in the second mold 284 (see FIG. 7D). Then, the cavity 44 in the second mold 284 is covered with the capacitor 44 by melting and filling the PPS resin that is the molding material of the housing 20 through the gate 286 provided in the second mold 284, and The appearance of the housing 20 (see FIGS. 3 and 4) is molded.

  In the second molding step, in the resultant product 288 installed in the cavity 285 in the second mold 284, the wall portion 227 is extended between the capacitor 44 and the gate 286. Thus, by extending the wall portion 227 between the capacitor 44 and the gate 286, the molten PPS resin filled in the cavity 285 from the gate 286 is prevented from flowing toward the capacitor 44 by the wall portion 227. It will be.

  And the fuel level gauge 100 is completed by assembling | attaching the magnet holder 30 grade | etc., To the housing 20 shape | molded by the above process by the assembly process similar to 1st embodiment (refer FIG.1 and FIG.2).

  In the second embodiment described so far, the connection of the magnetoelectric conversion element 42 to the detection element connecting portion 40a is performed before the first molding step, unlike the first embodiment performed after the first molding step. Is done. As described above, the connection of the magnetoelectric conversion element 42 to the detection element connection portion 40a may be before or after the first molding step as long as it is before the second molding step.

  In addition, in the second embodiment, the product 288 is arranged in the cavity 282 such that the wall portion 227 in which the positioning groove 25 is formed is located between the capacitor 44 and the gate 286. Accordingly, the flow rate of the PPS resin toward the capacitor 44 is hindered by the wall portion 227, so that the flow rate is reduced. As described above, when the PPS resin covers the capacitor 44, the resistance force acting on the capacitor 44 from the melted PPS resin is reduced. As described above, the covering portion 226 having the positioning groove 25 has a function of improving the reliability of connection by accurately positioning the capacitor 44 and a function of reducing the resistance force that causes the connection failure. Can be made. Therefore, poor connection between the capacitor 44 and the terminals 41a to 41c is reliably reduced. Therefore, even when the manufacturing method according to the second embodiment is used, the fuel level gauge 100 that maintains high detection accuracy is realized.

(Other embodiments)
As mentioned above, although several embodiment by this invention was described, this invention is limited to the said embodiment and is not interpreted and can be applied to various embodiment in the range which does not deviate from the summary.

  In the above embodiment, the products 88 and 288 are placed in the cavity 285 so that the positioning groove 25 is located between the capacitor 44 and the gate during the second molding step. As a result, the peripheral wall portion 227 or the wall portion 227 forming the positioning groove 25 exerts an action of hindering the flow of the PPS resin from the gate toward the capacitor 44. However, in the form in which the peripheral wall portion surrounding the periphery of the capacitor 44 is formed in the first molding step, the peripheral wall portion can cause the flow of the PPS resin without the positioning groove 25 being positioned between the capacitor 44 and the gate. It can exert a hindering action. Moreover, the form which implements the 2nd shaping | molding process which coat | covers the said capacitor | condenser 44, without providing the wall part which prevents the flow of PPS resin between the capacitor | condenser 44 and a gate may be sufficient.

  In the above embodiment, the depth of the positioning groove 25 is larger than the wire diameter of the leg portion 44b of the capacitor 44 and the dimension in the thickness direction of the main body portion 44a. However, the depth of the positioning groove 25 is not limited as long as the leg portion 44b can be positioned. The positioning groove 25 is formed with an electrode hole 29a for inserting an electrode 89 for welding. However, the electrode hole 29a may be omitted if the capacitor 44 and the terminals 41a to 41c can be connected.

  In the said embodiment, it demonstrated by the example using the capacitor | condenser 44 for removing the noise of the circuit part 40 as an electronic component as described in a claim. However, the electronic component is not limited to the capacitor 44 and may be a resistor or the like for adjusting the output level of the magnetoelectric conversion element 42, for example. In the above-described embodiment, the capacitor in the form in which the thin rod-like leg portion 44b extends from the main body portion 44a has been described as an example. However, in the electronic component, for example, the belt-like leg portion extends from the rectangular parallelepiped main body portion. It may be a so-called chip type form.

  In the above embodiment, the PPS resin has been described as an example of the material of the housing 20. However, the material of the housing 20 is not limited to PPS resin, and may be other resin materials. Further, the connection between the terminal, the magnetoelectric conversion element, and the electronic component may not be by welding.

  The present invention has been described based on the example in which the present invention is applied to the fuel level gauge 100 for vehicles. However, the application target of the present invention is not limited to the fuel level gauge 100, and other liquids mounted on the vehicle, for example, It may be a liquid level detecting device in a container such as brake fluid, engine cooling water, and engine oil. Furthermore, the present invention may be applied not only to the vehicle but also to a liquid level detection device in a liquid container provided in various consumer devices and various transport machines.

20 Housing (fixed body), 21 Shaft part, 24a, 24b Stopper wall, 25 Positioning groove, 25a Open end, 25b Closed end, 25c, 25d Side wall surface, 25e Bottom part, 26,226 Cover part, 27,227 Peripheral wall part, 27a Top surface, 28a Component housing part, 28b Element housing part, 29a Electrode hole (welding electrode hole), 29b Electrode hole (counter electrode hole), 29c Bottom part, 30 Magnet holder (rotating body), 31 Magnet, 32 Float arm fixed Part, 33 bearing part, 34 flange part, 35 stopper hole, 40 circuit part, 40a detection element connection part, 40b capacitor connection part (electronic component connection part), 41a, 41b, 41c terminal, 42 magnetoelectric conversion element (detection element) 42a Input / output unit, 44 Capacitor (electronic component), 44a Body unit, 44b Leg unit 50 Float arm, 51 Stopper part, 53 Float holding part, 60 Float, 61 Through hole, 70 Wiring, 72 Terminal part, 73 Lead wire, 81,281 First mold, 82,282 Cavity, 84,284 Second metal Mold, 85, 285 Cavity, 86, 286 Gate, 88, 287, 288 Result, 89 Electrode, 90 Fuel tank (container), 90a Ceiling surface, 90b Bottom surface, 91 Fuel (liquid), 91a Liquid surface, 93 Fuel pump Module (container), 100 Fuel level gauge (liquid level detector)

Claims (9)

A fixed body fixed to a container for storing liquid;
A rotating body that is rotatably supported by the fixed body and relatively rotates following the liquid level of the liquid stored in the container;
A terminal provided with a detecting element connecting portion and an electronic component connecting portion, a detecting element connected to the detecting element connecting portion and detecting an angle of the rotating body, and a main body portion and protruding from the main body portion and connected to the electronic component connecting portion And a circuit part embedded in the fixed body, and a method of manufacturing a liquid level detection device for detecting the height of the liquid level. ,
A longitudinal positioning groove in which the electronic component connection part is exposed at the bottom by installing the terminal in a cavity in the first mold and filling the cavity with the molding material of the fixed body, in the longitudinal direction A first forming step of forming a covering portion that covers the terminal, having a positioning groove that is a closed end that is closed at one end and an open end that is open at the other end in the longitudinal direction;
After the first molding step, the leg portion is connected to the electronic component connecting portion in a state where the electronic component is positioned by inserting the leg portion into the positioning groove from the open end toward the closed end. A connecting step to
The result of the connecting step is placed in a cavity in a second mold, and the cavity is filled with a molding material for the fixed body, thereby covering the electronic component and molding the appearance of the fixed body. And a process for producing the liquid level detecting device.   The dimension in the depth direction of the positioning groove formed in the first forming step is larger than a dimension of a cross section of the leg portion in a direction intersecting the protruding direction of the leg portion. The manufacturing method of the liquid level detection apparatus of description.   In the connecting step, in a state where the leg is pressed toward the electronic component connecting portion by an electrode, an electric current is applied between the leg portion and the electronic component connecting portion via the electrode, thereby welding the The method of manufacturing a liquid level detection device according to claim 1, wherein an electronic component is connected to the terminal. In the first forming step, by enlarging a part of the positioning groove in the width direction, the covering portion provided with a welding electrode hole having a shape corresponding to the shape of the electrode is formed,
4. The liquid level detection device according to claim 3, wherein in the connecting step, the electrode is inserted into the welding electrode hole, and the leg is pressed toward the electronic component connecting portion by the electrode. Method. The terminal is plate-shaped,
In the first forming step, the covering portion is formed such that a counter electrode hole that exposes the electronic component connection portion at the bottom faces the welding electrode hole in the plate thickness direction of the terminal,
In the connecting step, the electrode is inserted into each of the welding electrode hole and the counter electrode hole, and the leg portion and the electronic component connecting portion are sandwiched between the pair of electrodes, and the leg portion is connected to the electronic device. The method for manufacturing a liquid level detection device according to claim 4, wherein welding is performed to the component connection portion. The second mold is provided with a gate for filling the cavity with the molding material of the fixed body,
The said 2nd shaping | molding process WHEREIN: The said product is installed in the said cavity in the state in which the said positioning groove | channel is located between the said gate and the said electronic component, The Claim 1 characterized by the above-mentioned. The manufacturing method of the liquid level detection apparatus of description.   The said coating | coated part shape | molded in said 1st shaping | molding process has a surrounding wall part which surrounds the circumference | surroundings of the said electronic component connected in the said connection process, and is provided with the said positioning groove | channel. A method for producing the liquid level detection device according to claim 1. In the first molding step, the covering portion that covers the terminal in a state where the detection element connection portion is exposed is molded,
In the connection step, the detection element is connected to the detection element connection portion,
The method of manufacturing a liquid level detection device according to claim 1, wherein the detection element is covered together with the electronic component in the second molding step.   In the first molding step, the terminal in which the detection element is connected to the detection element connection portion is installed in a cavity in the first mold, and the covering portion that covers the detection element is molded together with the terminal. The manufacturing method of the liquid level detection apparatus as described in any one of Claims 1-7 characterized by the above-mentioned.

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