JP2010185740A - Sensor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sensor device facilitating reduction in size with less component items and having high reliability without performance deterioration caused by a measurement object liquid, moisture and the like. <P>SOLUTION: The sensor device includes: a detection part 21; electrodes for liquid level measurement provided on one side of the detection part 21; and a processing circuit 27 provided on the side of the detection part 21 and processing an output from the electrodes for liquid level measurement. A mold resin layer 29 entirely covering the processing circuit 27 is provided on the side of the detection part 21, and a laminate film 30 is fused on the side of the detection part 21 to entirely cover the electrodes for liquid level measurement and the mold resin layer 29. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a sensor device that detects the level and quality of liquid stored in a container, and more particularly to a sensor device that detects the level and quality of engine oil and fuel for automobiles, construction machines, and the like. .

  Generally, a sensor device as shown in FIG. 7 is known as a sensor device for detecting engine oil, fuel level, etc. of automobiles, construction machines and the like (see Patent Document 1).

  FIG. 7 is a cross-sectional view showing a state in which a conventional sensor device is held in a suspended manner on the top surface of a tank.

  In FIG. 7, 1 is a sensor device, 2 is a top surface of a tank that holds the sensor device 1, 3 is a base member that constitutes a part of the sensor device 1, and this base member 3 faces downward via a holder 4. The cylindrical electrode 5 extending to the inside and the internal electrode 6 disposed on the inside thereof are fixed without being in contact with each other, and are electrically connected to the cylindrical electrode 5 and the internal electrode 6 at the upper part thereof. The circuit board 7 is held. The base member 3 is attached to the top surface 2 of the tank via a packing 8. Further, a ring packing 9 is provided between the holder 4 and the internal electrode 6, and the base member 3 is interposed between the base member 3 and the holder 4. The ring packing 10 is provided to prevent the liquid to be measured and its vapor from leaking out of the tank.

  When the liquid level is measured, the detection unit intersects the liquid surface to be measured, and the portion immersed in the liquid increases or decreases as the liquid level rises and falls. The liquid level of the liquid to be measured is measured from the change in capacitance between the cylindrical electrode 5 and the internal electrode 6 due to the elevation of the liquid level.

As prior art document information relating to the invention of this application, for example, Patent Document 1 is known.
JP 2007-1113914 A

  However, in the above-described conventional sensor device, it is necessary to prepare many parts such as the circuit board 7, the base member 3, the holder 4, the cylindrical electrode 5, and the internal electrode 6 and to assemble them. However, it was difficult to reduce the size of the device as it increased. Further, in the conventional sensor device, since the liquid to be measured and its vapor are prevented from leaking out of the tank by using a large number of ring packings 9 and 10 having a large diameter, the circuit board 7 has the liquid to be measured. Although the circuit board 7 is not protected against moisture, dust, etc., it has a problem that the performance of the sensor device is deteriorated.

  The present invention solves the above-mentioned conventional problems, and provides a highly reliable sensor device that is easy to miniaturize with a small number of parts used, and that does not cause performance degradation due to the liquid to be measured or moisture. It is for the purpose.

  In order to achieve the above object, the present invention has the following configuration.

  The invention according to claim 1 of the present invention is a detection unit, a liquid level measurement electrode provided on one side surface of the detection unit, provided on one side surface of the detection unit, and the liquid And a processing circuit for processing the output from the level measuring electrode, a mold resin layer covering the entire processing circuit is provided on one side surface of the detection unit, and the entire liquid level measuring electrode and the mold resin are provided. A laminate film is fused to one side surface of the detection unit so as to cover the layer. According to this configuration, a mold resin layer that covers the entire processing circuit is provided on one side surface of the detection unit. In addition, since the laminate film is fused to one side of the detection unit so as to cover the entire liquid level measurement electrode and the mold resin layer, the liquid level measurement electrode and the processing circuit are placed on the detection unit. And can be formed integrally with Can protect the physical circuit and liquid level measuring electrode from the external environment, thereby, those having the effect that it is possible to easily provide a high sensor device reliable compact.

  The invention according to claim 2 of the present invention particularly includes a laminate film that covers the entire liquid level measurement electrode and the mold resin layer, a first laminate film that covers the entire liquid level measurement electrode, and the mold. A second laminate film covering the resin layer is formed, and a concave portion is previously formed in the second laminate film at a location corresponding to the mold resin layer. According to this configuration, the mold resin In the second laminate film that covers the layer, since the concave portion is formed in advance in the location corresponding to the mold resin layer, the portion that does not correspond to the mold resin layer in the second laminate film that covers the mold resin layer, Adhesion with the first laminate film covering the flat surface of the detection unit can be further increased, and this makes it small and highly reliable. And it has a effect that the sensor device can be easily provided.

  The invention according to claim 3 of the present invention covers, as a laminate film that covers the entire liquid level measurement electrode and the mold resin layer, a portion that covers the entire liquid level measurement electrode, and the mold resin layer. In this laminate film, a concave portion is formed in advance in a portion corresponding to the mold resin layer in a portion covering the mold resin layer in the laminate film. For example, as a laminate film covering the entire liquid level measurement electrode and the mold resin layer, a laminate film in which a portion covering the entire liquid level measurement electrode and a portion covering the mold resin layer are integrated, and In the part of the laminate film that covers the mold resin layer, a concave portion is provided in advance at a position corresponding to the mold resin layer. As a result, the adhesion between the portion of the laminate film that covers the mold resin layer that does not correspond to the mold resin layer and the plane of the detection unit can be increased, and the number of components can be reduced. As a result, it is possible to easily provide a small and highly reliable sensor device.

  According to a fourth aspect of the present invention, there is provided a detection unit, a liquid level measurement electrode provided on one side surface of the detection unit, provided on one side surface of the detection unit, and the liquid And a processing circuit for processing the output from the level measuring electrode, a mold resin layer covering the entire processing circuit is provided on one side surface of the detection unit, and the entire liquid level measuring electrode and the mold resin are provided. A laminate film is fused to one side surface of the detection unit so as to cover the layer, and a terminal electrically connected to the processing circuit is connected to the detection unit, the tip of which is the other side surface side of the detection unit The mounting member is inserted into the terminal via an O-ring, and a mortar-shaped recess is provided in the mounting member at a portion facing the O-ring. Insert the fixing ring into the Accordingly, the mortar-shaped recess in the mounting member is pressed against the O-ring, and according to this configuration, the liquid measuring electrode and the processing circuit can be integrally formed on the detection unit. In addition, the laminate film and the mold resin layer can be protected from the external environment, and the terminal for outputting a signal from the processing circuit can be directly attached to the detection unit while maintaining airtightness and watertightness. Thus, it is possible to easily provide a highly reliable sensor device.

  As described above, the sensor device of the present invention includes the detection unit, the liquid level measurement electrode provided on one side surface of the detection unit, the one side surface side of the detection unit, and the liquid level. A processing circuit for processing the output from the measurement electrode, a mold resin layer covering the entire processing circuit is provided on one side surface of the detection unit, and the entire liquid level measurement electrode and the mold resin layer are provided. Since the laminate film is fused to one side of the detection unit so as to cover the liquid level, the liquid level measuring electrode and the processing circuit can be integrally formed on the detection unit, and the processing circuit and the liquid level The measurement electrode can be protected from the external environment, and this provides an excellent effect that a small and highly reliable sensor device can be easily provided.

  Hereinafter, a sensor device according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a front view of a detection unit of a sensor device according to Embodiment 1 of the present invention. In FIG. 1, reference numeral 21 denotes a detection made of a rectangular polyimide film having a thickness of about 120 μm and extending vertically. The first detection electrode 22 and the second detection electrode are formed in a comb-like shape with carbon, silver or the like having a thickness of about 15 μm from the lower end to the upper end on one side of the detection unit 21. 23, a liquid level measuring electrode comprising a third detection electrode 24 is provided. The first, second, and third detection electrodes 22, 23, and 24 are connected to the signal processing unit 26 by lead wires 25 extending vertically.

  2 is a cross-sectional view taken along the line AA of FIG. 1. In FIG. 2, reference numeral 27 denotes a processing circuit composed of an IC, a capacitor, a resistor, etc., and 28 is electrically connected to the processing circuit 27. And the other end of the detection unit 21 is provided on the other side surface of the detection unit 21 so as to protrude. One end of the processing circuit 27 and the terminal 28 located on one side surface of the detection unit 21 is covered with a mold resin layer 29 made of epoxy resin or the like, and the first detection electrode 22 and the second detection electrode 22 A laminate film 30 is fused so as to cover the liquid level measuring electrode (not shown) comprising the detection electrode 23 and the third detection electrode 24, the lead wire 25 and the mold resin layer 29. is there. Further, an attachment member 32 is fitted into the terminal 28 whose other end protrudes from the other side surface of the detection portion 21 via an O-ring 31, and the attachment member 32 faces the O-ring 31. A mortar-shaped concave portion 33 is provided in a portion to be fixed, and a fixing ring 34 is fitted and fixed to the other end portion of the terminal 28, whereby the mortar-shaped concave portion 33 in the mounting member 32 is pressed against the O-ring 31. I am trying to make it. With such a configuration, the liquid level measurement electrode and the processing circuit 27 can be integrally formed on the detection unit 21, and the laminate film 30 and the mold resin layer 29 can protect them from the external environment. Furthermore, since the terminal 28 for outputting a signal from the processing circuit 27 can be directly attached to the detection unit 21 while maintaining airtightness and watertightness, a small and highly reliable sensor device can be easily provided. The effect that it can be obtained.

  Next, a method for assembling the sensor device according to Embodiment 1 of the present invention configured as described above will be described with reference to the drawings.

  3 (a) to 3 (d) and FIGS. 4 (a) to 4 (c) show the assembly process diagram of the sensor device according to the first embodiment of the present invention, focusing on the cross section along the line AA of the sensor device shown in FIG. It is shown.

  First, as shown in FIG. 3A, first, second, and third detection electrodes 22, 23, and 24 (not shown), a lead wire 25, and a processing circuit wiring 35 are formed on one side surface of the detection portion 21. Is formed by a method such as printing and drying, and then an IC, a capacitor, a resistor, and the like are soldered to the processing circuit wiring 35 to form the processing circuit 27.

  Next, as shown in FIG. 3B, the terminal 28 is inserted into a hole provided in the detection unit 21 in advance, and one end of the terminal 28 and the processing circuit wiring 35 are soldered and electrically connected.

  Next, as shown in FIG. 3C, one end of the processing circuit 27 and the terminal 28 located on one side surface of the detection unit 21 is covered with a mold resin layer 29 made of epoxy resin or the like, and dried. , Cure.

  Next, as shown in FIG. 3 (d), a liquid level measuring electrode (not shown) comprising the first detection electrode 22, the second detection electrode 23, and the third detection electrode 24, a lead wire 25, and A laminate film 30 covering the entire mold resin layer 29 is prepared.

  Next, as shown in FIG. 4A, heat and pressure are applied to the laminate film 30 from the first detection electrode 22, the second detection electrode 23, and the third detection electrode 24 (not shown). The detection unit 21 including the liquid level measurement electrode, the lead wire 25 and the mold resin layer 29 and the laminate film 30 are fused.

  Next, as shown in FIG. 4B, the attachment member 32 is fitted and inserted into the other end portion of the terminal 28 protruding to the other side surface side of the detection portion 21 via the O-ring 31. Here, the mounting member 32 is provided with a mortar-shaped recess 33 at a portion facing the O-ring 31.

  Finally, as shown in FIG. 4 (c), a fixing ring 34 is fitted and fixed to the other end of the terminal 28, so that the mortar-shaped recess 33 in the mounting member 32 is pressed against the O-ring 31. Is. With such a configuration, since the O-ring 31 is in close contact with the detection unit 21 and the terminal 28, it is possible to prevent liquid or a substrate from entering the processing circuit 27 part from the terminal 28 part. is there.

  As described above, in the first embodiment of the present invention, the liquid level measurement electrode and the processing circuit 27 are integrally formed on the detection unit 21, and the processing circuit 27 and the liquid are formed by the laminate film 30 and the mold resin layer 29. The position measuring electrode is protected from the external environment, and the terminal 28 for outputting a signal from the processing circuit 27 is directly attached to the detection unit 21 while maintaining airtightness and watertightness. Therefore, the sensor device is small and reliable. Can be provided easily.

  5 (a) to 5 (c) show an assembly process diagram of the sensor device according to the second embodiment of the present invention, paying attention to a cross-section taken along line AA of the sensor device shown in FIG.

  FIG. 5A shows the same configuration as that of FIG. 3C described above, that is, the processing circuit 27 and one end portion of the terminal 28 located on one side surface portion of the detection portion 21 are connected with epoxy. It shows a state where it is covered with a mold resin layer 29 made of resin or the like, and then dried and cured.

  Next, as shown in FIG. 5B, a liquid level measurement electrode (not shown) comprising the first detection electrode 22, the second detection electrode 23, and the third detection electrode 24, and the lead wire 25 A first laminate film 36 that covers the whole and a second laminate film 37 that covers the mold resin layer 29 are prepared. Here, a concave portion 37 a is formed in advance in a portion corresponding to the mold resin layer 29 in the second laminate film 37, and a portion corresponding to the mold resin layer 29 is formed in the first laminate film 36. The hole 36a is formed.

  Next, as shown in FIG. 5 (c), a liquid composed of the first detection electrode 22, the second detection electrode 23, and the third detection electrode 24 by applying heat and pressure to the first laminate film 36. The position measuring electrode (not shown), the detection unit 21 including the lead wire 25, and the first laminate film 36 are fused. Further, heat and pressure are applied to the second laminate film 37 to fuse the mold resin layer 29, the first laminate film 36, and the second laminate film 37 together.

  The subsequent assembly process is the same as that of the sensor device according to the first embodiment of the present invention, and the description thereof is omitted.

  In the second embodiment of the present invention described above, the entire liquid level measurement electrode (not shown) and the laminate film covering the mold resin layer 29 are covered with the entire liquid level measurement electrode (not shown). A first laminate film 36 and a second laminate film 37 covering the mold resin layer 29 are formed, and a concave portion 37a is formed in advance in the second laminate film 37 at a location corresponding to the mold resin layer 29. Therefore, the adhesion between the portion of the second laminate film 37 that covers the mold resin layer 29 that does not correspond to the mold resin layer 29 and the first laminate film 36 that covers the plane of the detection unit 21 is higher. Thus, it is possible to easily provide a small and highly reliable sensor device. .

  6 (a) to 6 (c) show an assembly process diagram of the sensor device according to the third embodiment of the present invention, paying attention to a cross-sectional portion taken along line AA of the sensor device shown in FIG.

  FIG. 6A shows the same configuration as that of FIG. 3C described above. That is, the processing circuit 27 and one end portion of the terminal 28 located on one side surface portion of the detection portion 21 are connected with epoxy. It shows a state where it is covered with a mold resin layer 29 made of resin or the like, and then dried and cured.

  Next, as shown in FIG. 6B, a liquid level measurement electrode (not shown) comprising the first detection electrode 22, the second detection electrode 23, and the third detection electrode 24 and the lead wire 25. A laminate film 38 is prepared in which a part covering the whole and a part covering the mold resin layer 29 are integrated. Here, the laminate film 38 is formed with a recess 38 a in advance at a location corresponding to the mold resin layer 29.

  Next, as shown in FIG. 6C, heat and pressure are applied to the laminate film 38 to measure the liquid level comprising the first detection electrode 22, the second detection electrode 23, and the third detection electrode 24. The plane of the detection unit 21 including the electrode (not shown) and the lead wire 25, the mold resin layer 29, and the laminate film 38 are fused.

  The subsequent assembly process is the same as that of the sensor device according to the first embodiment of the present invention, and the description thereof is omitted.

  In the above-described third embodiment of the present invention, a laminate film 38 in which a portion covering the whole liquid level measuring electrode (not shown) and a portion covering the mold resin layer 29 are integrated is used, and this laminate is used. In the portion of the film 38 that covers the mold resin layer 29, a recess 38 a is formed in advance at a location corresponding to the mold resin layer 29, so that the mold resin layer 29 in the laminate film 38 that covers the mold resin layer 29 is formed. In addition, it is possible to further increase the adhesion between the non-corresponding portion and the plane of the detection unit 21 and reduce the number of components, thereby easily providing a small and highly reliable sensor device. It has the effect of being able to.

  The sensor device according to the present invention has the advantage that it can be easily reduced in size due to the number of parts used, and can provide a highly reliable sensor device without causing performance degradation due to the liquid to be measured or moisture. In particular, it is useful as a sensor device for detecting the level of engine oil or fuel in automobiles, construction machines, and the like.

The front view of the detection part of the sensor apparatus in one embodiment of this invention AA line sectional view of FIG. (A)-(d) Assembly process drawing of the sensor device (A)-(c) Assembly process drawing of the sensor device (A)-(c) Assembly process figure of sensor apparatus in Embodiment 2 of this invention (A)-(c) Assembly process figure of sensor apparatus in Embodiment 3 of this invention Sectional view of a conventional sensor device

DESCRIPTION OF SYMBOLS 21 Detection part 27 Processing circuit 28 Terminal 29 Mold resin layer 30 Laminated film 31 O-ring 32 Mounting member 33 Concave part 34 Fixing ring 36 1st laminating film 37 2nd laminating film 37a Concave part 38 Laminating film 38a Concave part

Claims (4)

A detection unit, a liquid level measurement electrode provided on one side surface of the detection unit, and a processing circuit provided on one side surface of the detection unit and processing an output from the liquid level measurement electrode A mold resin layer covering the entire processing circuit is provided on one side surface of the detection unit, and a laminate film is disposed on the detection unit so as to cover the entire liquid level measurement electrode and the mold resin layer. Sensor device fused to one side. A laminate film that covers the entire liquid level measurement electrode and the mold resin layer is composed of a first laminate film that covers the entire liquid level measurement electrode and a second laminate film that covers the mold resin layer, The sensor device according to claim 1, wherein a concave portion is formed in advance in a portion corresponding to the mold resin layer in the second laminate film. As a laminate film covering the entire liquid level measuring electrode and the mold resin layer, a laminate film in which a portion covering the entire liquid level measuring electrode and a portion covering the mold resin layer is integrated is used, and this laminate is used. The sensor device according to claim 1, wherein a concave portion is formed in advance in a portion corresponding to the mold resin layer in a portion of the film covering the mold resin layer. A detection unit, a liquid level measurement electrode provided on one side surface of the detection unit, and a processing circuit provided on one side surface of the detection unit and processing an output from the liquid level measurement electrode A mold resin layer covering the entire processing circuit is provided on one side surface of the detection unit, and a laminate film is disposed on the detection unit so as to cover the entire liquid level measurement electrode and the mold resin layer. A terminal that is fused to one side surface and further electrically connected to the processing circuit is provided on the detection unit such that a tip portion protrudes to the other side surface of the detection unit, and an O terminal is provided on the terminal. While fitting the mounting member through the ring, the mounting member is provided with a mortar-shaped recess in the portion facing the O-ring, and further by inserting and fixing the fixing ring to the tip of the terminal, The mounting member Rusuribachi shaped sensor device the recess so as to press said O-ring.

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