JP2010164348A - Fuel property sensor and fuel tank - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensive and simple fuel property sensor detecting the component contained in fuel before the fuel enters an engine, and a fuel tank. <P>SOLUTION: The fuel property sensor 10 includes a swelling member 14 consisting of a substance swollen by the component contained in the fuel 12 to be changed in volume and a detection part 16 detecting the component on the basis of a change in the volume of the swelling member 14. The fuel tank 100 includes the fuel property sensor 10 arranged so that the swelling member 14 may be exposed at a predetermined position of the inner wall surface on the basis of the SP value of the component contained in the fuel 12 and the SP value of the swelling member 14. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a fuel property sensor and a fuel tank.

  In recent years, there has been a concern about the deterioration of fuel. Heavy oils such as benzene and toluene, which are inferior components, deteriorate the startability of the engine and have a great adverse effect on the exhaust gas. In addition, diversification of fuel is predicted. Ethanol, which is expected to be used as a multi-fuel, is highly aggressive against aluminum and rubber that make up engines. Therefore, it is required to detect heavy oil and ethanol in advance in a fuel tank before entering the engine so that heavy oil and ethanol contained in the fuel do not enter the engine. A fuel property sensor for detecting heavy oil or ethanol needs to be installed in the fuel tank. Further, it is desirable that the fuel property sensor has an inexpensive and simple configuration.

  Patent Document 1 describes a fuel property detection device capable of detecting both an index correlated with the alcohol concentration of a fuel containing alcohol and an index correlated with the density of the fuel.

JP 2008-107098 A

  However, since the fuel property detection device described in Patent Document 1 determines the property of the fuel after the fuel is burned in the engine, there is a problem that it is not possible to prevent a bad component from entering the engine.

  The present invention has been made in view of the above problems, and it is an object of the present invention to provide an inexpensive and simple fuel property sensor and fuel tank that detect components contained in the fuel before the fuel enters the engine. To do.

  The present invention includes a swelling member made of a substance that swells and changes in volume due to a component contained in the fuel, and a detection unit that detects the component based on the change in the volume of the swelling member. This is a fuel property sensor. Thereby, before the fuel enters the engine, components contained in the fuel can be detected with a cheaper and simpler configuration.

  The said structure WHEREIN: It has a some said swelling member which has different SP value, The said detection part can be set as the structure which detects the said component based on the change of each said volume of the said swelling member. Thereby, the density | concentration of the component which a fuel contains can be measured with a sufficient precision.

  The present invention has the above fuel property sensor arranged so that the swelling member is exposed at a predetermined position on the inner wall surface based on the SP value of the component and the SP value of the swelling member. It is a fuel tank characterized by this. When fuels of different polarities (ethanol, water, etc.) are mixed, phase separation occurs, and each component is distributed at different positions in the fuel tank according to specific gravity. Further, the SP value of each component is different. By disposing a swelling member having an SP value equal to the SP value of each component at a position where each component is distributed in the fuel tank, each component of the fuel in which phase separation occurs can be detected. Therefore, measurement defects can be reduced.

  According to this configuration, the components contained in the fuel can be detected with a cheaper and simpler configuration before the fuel enters the engine.

FIG. 1A and FIG. 1B are schematic views illustrating a cross section of the fuel property sensor according to the first embodiment. FIG. 2 is a graph showing a relationship between the change in the SP value of the fuel and the change in the volume expansion coefficient of the swelling member according to the first embodiment. FIG. 3A is a graph showing the relationship between the change in the concentration of heavy oil contained in the fuel according to Example 1 and the change in the SP value of the fuel. FIG. 3B is a graph showing the relationship between the change in the concentration of ethanol contained in the fuel and the change in the SP value of the fuel according to the first embodiment. FIG. 4 is a schematic diagram illustrating a cross section of the fuel property sensor according to the second embodiment. FIG. 5 is a graph showing the relationship between the change in the SP value of the fuel according to Example 2 and the change in the volume expansion coefficient of the swelling member. FIG. 6 is a diagram illustrating a relationship between whether or not the detection unit according to the second embodiment can detect the pressure received from the expansion member and the concentration of heavy oil included in the fuel. FIG. 7 is a schematic diagram illustrating a cross section of the fuel tank according to the third embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  With reference to FIG. 1, the structure of the fuel property sensor 10 arrange | positioned on the inner wall face of the fuel tank 100 based on Example 1 is demonstrated. FIGS. 1A and 1B are schematic views showing a cross section of the fuel property sensor 10. As shown in FIGS. 1A and 1B, the fuel property sensor 10 includes a swelling member 14, a detection unit 16, and a net 18. The swelling member 14, the detection unit 16, and the net 18 are supported by the housing 20. The fuel property sensor 10 is disposed so that the swelling member 14 is exposed on the inner wall surface of the fuel tank 100, and is immersed in the fuel 12. The fuel 12 is, for example, gasoline. The swelling member 14 is swollen by the components included in the fuel 12 and has a property of changing its volume. The swelling member 14 is, for example, rubber or resin. Components contained in the fuel 12 are, for example, benzene, toluene, and ethanol which are heavy oils. The detection unit 16 is a pressure sensor that detects a component contained in the fuel 12 by detecting a pressure received from the swelling member 14 based on a change in the volume of the swelling member 14. The net 18 is provided in a portion of the periphery of the swelling member 14 excluding a portion where the swelling member 14 and the detection unit 16 face each other. The swelling member 14 comes into contact with the fuel 12 through the net 18. The swelling member 14 can be expanded only in the direction facing the detection unit 16 by the net 18.

  FIG. 1A shows the state of the fuel property sensor 10 before the volume of the swelling member 14 expands due to the components contained in the fuel 12. FIG. 1B shows that the swelling member 14 expands in the direction (indicated by the arrow in FIG. 1B) in which the volume of the swelling member 14 faces the detection unit 16 due to the components contained in the fuel 12. The state of the fuel property sensor 10 when it contacts 16 is shown. The detection part 16 detects the pressure of the direction which the arrow in FIG.1 (b) shows from the swelling member 14. FIG. This pressure is proportional to the volume expansion coefficient of the swelling member 14 described later.

  With reference to FIG. 2, the relationship between the change of the SP (Solubility Parameter) value of the fuel 12 and the change of the volume expansion coefficient of the swelling member 14 will be described. FIG. 2 is a graph in which the horizontal axis represents the change in the SP value of the fuel 12 and the vertical axis represents the change in the volume expansion coefficient of the swelling member 14. The SP value is called a dissolution parameter, and the swelling member 14 and the fuel 12 have unique SP values. As will be described later, the SP value of the fuel 12 varies depending on the concentration of components contained in the fuel 12. The swelling member 14 rapidly expands in volume as the SP value of the swelling member 14 approaches the SP value of the fuel 12, and the pressure received by the detection unit 16 also increases. When the SP value of the swelling member 14 and the SP value of the fuel 12 are equal, the volume expansion coefficient is maximized, and the pressure received by the detection unit 16 is also maximized.

  Hereinafter, description will be made assuming that the SP value of the swelling member 14 is SP2. As shown in FIG. 2, the volume expansion coefficient of the swelling member 14 changes as a curve 30 according to the change in the SP value of the fuel 12.

  In the section from SP1 to SP3 where the SP value of the fuel 12 is substantially equal to the SP value of the swelling member 14, the volume expansion coefficient of the swelling member 14 changes abruptly from E1 to E2 as shown in the graph from the point 32 to the point 36. To do. When the SP value of the fuel 12 is equal to SP2, the volume expansion coefficient of the swelling member 14 is the maximum E2 as indicated by a point 34. By detecting the pressure corresponding to the volume expansion coefficient from E1 to E2 by the detection unit 16, it is possible to predict that the SP value of the fuel 12 is a value in the section from SP1 to SP3.

  FIG. 3A is a graph showing the relationship between the change in the concentration of heavy oil contained in the fuel 12 and the change in the SP value of the fuel 12. The horizontal axis of the graph in FIG. 3A indicates the concentration of heavy oil contained in the fuel 12, and the vertical axis indicates the change in the SP value of the fuel 12. Point 40 indicates the SP value for gasoline. Point 42 indicates the SP value when the concentration of benzene, which is heavy oil, is 100%, and the SP value is SP4. Point 44 indicates the SP value when the concentration of toluene, which is heavy oil, is 100%, and the SP value is SP5.

  As shown in FIG. 3A, as the concentration of benzene contained in gasoline approaches 100%, the SP value of the fuel 12 increases and changes from point 40 to point 42 as indicated by a solid line 46. As the concentration of benzene contained in gasoline increases, the engine becomes difficult to start in a low temperature state, and eventually reaches the limit at which the engine cannot be started. When the concentration of benzene at the low temperature start limit is C1, and the SP value of benzene is SP6, a point 48 is indicated. By selecting the swelling member 14 having an SP value of SP6 or more, it is possible to detect a fuel containing benzene and inferior in cold start performance.

  Similarly, as shown in FIG. 3A, as the concentration of toluene contained in gasoline approaches 100%, the SP value of the fuel 12 increases and changes from a point 40 to a point 44 as indicated by a solid line 47. . When the toluene concentration at the low temperature start limit is C1, and the SP value of toluene is SP7, a point 49 is indicated. By selecting the swelling member 14 having an SP value of SP7 or more, it is possible to detect a fuel including toluene that has poor low-temperature starting performance.

  From FIG. 3A, by selecting the swelling member 14 whose SP value is equal to SP7, it is possible to detect a fuel with low cold start performance including both benzene and toluene.

  FIG. 3B is a graph showing the relationship between the change in the concentration of ethanol contained in the fuel 12 and the change in the SP value of the fuel 12. The horizontal axis of the graph in FIG. 3B indicates the concentration of ethanol contained in the fuel 12, and the vertical axis indicates the change in the SP value of the fuel 12. Point 50 indicates the SP value for gasoline. A point 52 indicates the SP value when the ethanol concentration is 100%, and the SP value is SP8.

  As shown in FIG. 3B, as the ethanol concentration of gasoline approaches 100%, the SP value of the fuel 12 decreases and changes from a point 50 to a point 52 as indicated by a solid line 54. As the concentration of ethanol in gasoline increases, the attack on the engine material increases and eventually reaches an acceptable limit. When the concentration of ethanol at the material attack limit is C2, and the SP value of ethanol is SP9, a point 56 is shown. By selecting the swelling member 14 having an SP value of SP9 or less, it is possible to detect a fuel having high material attack performance including ethanol.

  According to the first embodiment, as shown in FIGS. 1 (a) and 1 (b), the fuel property sensor 10 includes a swelling member 14 made of a substance that swells due to components contained in the fuel 12 and changes in volume, and a swelling. And a detection unit 16 that detects a component contained in the fuel 12 based on a change in the volume of the member 14. As a result, before the fuel enters the engine, it is possible to detect a fuel having a low temperature start performance, including heavy oil, or a fuel having a high material attack performance, including ethanol, with a cheaper and simpler configuration. it can.

  According to the first embodiment, the fuel property sensor 10 includes the net 18 provided in a portion of the periphery of the swelling member 14 excluding a portion where the swelling member 14 and the detection unit 16 face each other. The swelling member 14 can be expanded only in the direction facing the detection unit 16 by the net 18. Therefore, a change in the volume of the swelling member 14 can be detected efficiently.

  In the first embodiment, the swelling member 14 of the fuel property sensor 10 is an example of rubber or resin, but may be another member having a property that the volume expands due to a component contained in the fuel.

  With reference to FIG. 4, the structure of the fuel property sensor 60 according to the second embodiment will be described. FIG. 4 is a schematic diagram illustrating a cross section of the fuel property sensor 60 according to the second embodiment. Hereinafter, a different point from the structure of the fuel property sensor 10 of FIG. 1 is demonstrated, and description of the structure which attaches | subjects the same code | symbol as FIG. 1 is abbreviate | omitted. The fuel property sensor 60 includes two swelling members 62 and 64 having different SP values, and the detection units 66 and 68 detect components included in the fuel 12 based on changes in the respective volumes of the swelling members 62 and 64. This is different from the fuel property sensor 10. The net | network 19 is provided in the part of each circumference | surroundings of the swelling members 62 and 64 except the part which the swelling members 62 and 64 and the detection parts 66 and 68 oppose, respectively. The swelling members 62 and 64 are in contact with the fuel 12 through the net 19. By the net 19, the swelling members 62 and 64 can be expanded only in the direction facing the detection parts 66 and 68, respectively.

  The relationship between the change in the SP value of the fuel 12 and the change in the volume expansion coefficient of the swelling members 62 and 64 will be described with reference to FIG. FIG. 5 is a graph showing changes in the SP value of the fuel 12 on the horizontal axis and changes in the volume expansion rates of the swelling members 62 and 64 on the vertical axis.

  In the following description, it is assumed that the SP value of the swelling member 62 is SP11 and the SP value of the swelling member 64 is SP15. The fuel 12 includes a component that is heavy oil. It is assumed that the detectors 66 and 68 detect pressures whose volume expansion rates correspond to E3 to E4.

  As shown in FIG. 5, the volume expansion coefficients of the swelling members 62 and 64 change as curves 70 and 80, respectively, according to changes in the SP value of the fuel 12.

  For example, when the SP value of the fuel 12 is SP11, the volume expansion coefficient of the swelling member 62 is E4 as indicated by a point 74. Therefore, the detection unit 66 can detect the pressure corresponding to E4. On the other hand, the volume expansion coefficient of the swelling member 64 is E5 as indicated by a point 88, and the pressure corresponding to E5 does not reach the pressure corresponding to E3 to E4 that can be detected by the detection unit 68. Therefore, the detection unit 68 cannot detect the pressure corresponding to E5.

  For example, when the SP value of the fuel 12 is SP13, the volume expansion coefficients of the swelling members 62 and 64 are both E6 as indicated by a point 90. The pressure corresponding to E6 reaches the pressure corresponding to E3 to E4 that can be detected by both the detection units 66 and 68. Therefore, the detection parts 66 and 68 can detect the pressure corresponding to E6.

  For example, when the SP value of the fuel 12 is SP15, the volume expansion coefficient of the swelling member 62 is E5 as indicated by a point 78, and the pressure corresponding to E5 is the pressure corresponding to E3 to E4 that can be detected by the detection unit 66. Not reach. Therefore, the detection unit 66 cannot detect the pressure corresponding to E5. On the other hand, the volume expansion coefficient of the swelling member 64 is E4 as indicated by a point 84. Therefore, the detection unit 68 can detect the pressure corresponding to E4.

  FIG. 6 shows whether or not the pressures received by the detectors 66 and 68 from the swelling members 62 and 64 when the SP values of the fuel 12 shown above are SP11, SP13, and SP15, respectively, and the weight that the fuel 12 contains. It is the figure which showed the relationship with the density | concentration of quality oil. Rows 92, 94 and 96 correspond to the case where the SP value of fuel 12 is SP11, SP13 and SP15, respectively.

  The row 92 indicates that when the SP value of the fuel 12 is SP11, the detection unit 66 can detect the pressure from the swelling member 62, and the detection unit 68 cannot detect the pressure from the swelling member 64. At this time, it can be predicted from FIG. 5 that the SP value of the fuel 12 is the value of the SP12 section corresponding to the point 82 from the SP10 corresponding to the point 72. Therefore, it can be determined that the heavy oil concentration is low.

  The row 94 indicates that when the SP value of the fuel 12 is SP13, the detection units 66 and 68 can detect the pressure from the swelling members 62 and 64. At this time, it can be predicted from FIG. 5 that the SP value of the fuel 12 is a value in the section from SP12 corresponding to the point 82 to SP14 corresponding to the point 76. Therefore, it can be determined that the concentration of heavy oil is moderate.

  The row 96 indicates that when the SP value of the fuel 12 is SP15, the detection unit 66 cannot detect the pressure from the swelling member 62 and the detection unit 68 can detect the pressure from the swelling member 64. At this time, it can be predicted from FIG. 5 that the SP value of the fuel 12 is the value in the section from SP14 corresponding to the point 76 to SP16 corresponding to the point 86. Therefore, it can be determined that the concentration of heavy oil contained in the fuel 12 is high.

  According to the second embodiment, as illustrated in FIG. 4, the plurality of swelling members 62 and 64 having different SP values are included, and the detection units 66 and 68 are based on the respective volume changes of the swelling members 62 and 64. It can be set as the structure which detects the component which the fuel 12 contains. Thereby, the density | concentration of the component which a fuel contains can be measured with a sufficient precision.

  In the second embodiment, the fuel property sensor 60 has an example of a configuration having a plurality of swelling members and a plurality of detection units, but other configurations may be used. For example, a plurality of fuel property sensors 10 of FIG. 1 having swelling members having different SP values may be used. Further, for example, the fuel property sensor has a plurality of swelling members and one detection unit, and one detection unit detects each change for each region where the plurality of swelling members are in contact. Also good.

  In Example 2, the example of the fuel property sensor which detects heavy oil was shown. For example, a fuel property sensor that detects both heavy oil and ethanol may be configured using a swelling member that swells with heavy oil and a swelling member that swells with ethanol.

  With reference to FIG. 7, the structure of the fuel tank 100 which concerns on Example 3 is demonstrated. FIG. 7 is a schematic diagram illustrating a cross section of the fuel tank 100 according to the third embodiment. As shown in FIG. 7, the fuel 102 is stored in the fuel tank 100. A fuel property sensor 104 for detecting heavy oil is disposed at the upper portion of the inner wall surface of the fuel tank 100, and a fuel property sensor 106 for detecting ethanol is disposed at the lower portion of the inner wall surface. The SP value of the swelling member included in the fuel property sensor 104 is substantially equal to the SP value of heavy oil. The SP value of the swelling member included in the fuel property sensor 106 is substantially equal to the SP value of ethanol. Since phase separation occurs between heavy oil and ethanol having different polarities, heavy oil is distributed in the upper part of the fuel 102 and ethanol is distributed in the lower part of the fuel 102. Moreover, the SP values of heavy oil and ethanol are different. Therefore, by disposing fuel property sensors 104 and 106 for detecting heavy oil and ethanol at positions where heavy oil and ethanol are distributed in the fuel tank, it is possible to detect each component of the fuel in which phase separation occurs. Therefore, measurement defects can be reduced.

  According to the third embodiment, as shown in FIG. 7, the fuel tank 100 has an inner wall surface based on the SP value of the component included in the fuel 102 and the SP value of the swelling members of the fuel property sensors 104 and 106. The fuel property sensors 104 and 106 are arranged so that the swelling member is exposed at a predetermined position. Thereby, the component which the fuel 102 in which phase separation generate | occur | produces can be detected. Therefore, measurement defects can be reduced.

  The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to such specific embodiments, and various modifications can be made within the scope of the gist of the present invention described in the claims.・ Change is possible.

DESCRIPTION OF SYMBOLS 10 Fuel property sensor 12 Fuel 14 Swelling member 16 Detection part 18 Net 19 Net 20 Case 60 Fuel property sensor 62 Swelling member 64 Swelling member 66 Detection part 68 Detection part 100 Fuel tank 102 Fuel 104 Fuel property sensor 106 Fuel property sensor

Claims (3)

A swelling member made of a substance that swells by a component contained in the fuel and changes in volume;
A detection unit for detecting the component based on a change in volume of the swelling member;
A fuel property sensor comprising:   2. The fuel property sensor according to claim 1, wherein the fuel property sensor includes a plurality of the swelling members having different SP values, and the detection unit detects the component based on a change in a volume of each of the swelling members.   3. The fuel property sensor according to claim 1, wherein the fuel property sensor is disposed so that the swelling member is exposed at a predetermined position on an inner wall surface based on an SP value of the component and an SP value of the swelling member. A fuel tank characterized by that.

Images