JP6623982B2 - Fuel pump control device - Google Patents

Description

  The present invention relates to a fuel pump control device that controls driving of a fuel pump for supplying fuel in a fuel tank to an engine.

  Conventionally, a fuel pump control device is configured by soldering electronic components to a printed circuit board. When the fuel pump control device is miniaturized, electronic components are densely packed, so that the self-heating of the product increases. This shortens the solder life. Further, if the electronic component is sealed with a resin for protection from external force, the thermal stress acting on the electronic component increases, and the life of the solder is shortened.

  Therefore, a technique for estimating the life of the solder is disclosed in Patent Document 1. In Patent Literature 1, a conductive member that connects between two connection parts on a substrate is provided in order to predict the solder life. Then, it is detected that the conductive member is detached from the connection portion during use, and when detached, it is determined that a defect has occurred in the solder.

JP 2015-90332 A

  As described above, the solder life of the fuel pump control device tends to be short, and thus there is a possibility that a defect may occur in the solder during use. If the fuel pump control device does not function due to the occurrence of a defect in the solder, there is a possibility that the fuel cannot be supplied and the engine cannot be driven. It is necessary to avoid stopping the driving of the engine while the vehicle is running, because it may cause a failure.

  However, the technology described in Patent Document 1 does not disclose a fail-safe process after the occurrence of a defect, even though the defect of the solder can be found. As described above, in order to avoid driving stop of the engine while the vehicle is running, when a defect is found in the solder, it is necessary to perform a fail-safe process suitable for the fuel pump control device.

  Therefore, the present invention has been made in view of the above-described problem, and it is possible to prevent the engine from being stopped due to a failure of the fuel pump control device when an abnormal tendency of solder is detected during driving of the engine. It is an object of the present invention to provide a fuel pump control device which can be used.

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

The fuel pump control device of the present invention is a fuel pump control device (13) for controlling the driving of a fuel pump (12) for supplying fuel in a fuel tank (11) to an engine. A drive circuit (22) for supplying, a control circuit (21) for controlling the drive circuit to control the power supplied to the fuel pump, and detecting an electronic component having a shorter solder life than the electronic components forming the control circuit. The control circuit (21) includes a detection unit (23) having components (23a, 23b) and a temperature sensor (26) for detecting the temperature of the control circuit. When the control circuit detects an abnormal state that is different from the conducting state in which the conducting state of the detecting component is conducting, and when the engine is running, the deterioration of the solder deterioration due to temperature change is monitored. To To win, the temperature detected by the temperature sensor to control the output of the drive circuit (22) to be within a predetermined range.

  According to the present invention, there is provided a detection component having a shorter solder life than the electronic components constituting the control circuit, and the control circuit monitors the energization state of the detection component. Since the detection component has a shorter solder life than the electronic component of the control circuit, the solder of the detection component ends its life earlier, and the conduction state becomes an abnormal state different from the conduction state. Therefore, the control circuit can detect that the life of the solder of the electronic component is near before the solder of the electronic component of the control circuit becomes defective.

Then, when the control circuit detects an abnormal state of the detection component and the engine is being driven , the temperature detected by the temperature sensor is reduced to a predetermined value in order to suppress the progress of solder deterioration due to a temperature change. The output of the drive circuit is controlled to be within the range . It is not preferable to stop the engine immediately upon detecting an abnormal state, for example, in the case of an engine of a vehicle, because the vehicle suddenly stops during traveling. Therefore, the output of the drive circuit is controlled so that the temperature detected by the temperature sensor falls within a predetermined range . Even if an abnormality occurs in the detection component, it does not mean that an abnormality has occurred in the electronic component of the control circuit. Therefore, even if the engine is driven, the normal state can be maintained for a while. However, if the temperature change of the control circuit is increased, the deterioration of the solder of the electronic components of the control circuit is accelerated. Therefore, the temperature change of the control circuit is reduced by controlling the output of the drive circuit.

  Note that the reference numerals in parentheses of the above-described units are examples showing the correspondence with specific units described in the embodiments described later.

The figure which shows the fuel supply system of 1st Embodiment in a simplified manner. FIG. 2 is a simplified block diagram showing a fuel pump control device. 9 is a flowchart illustrating a process based on an output of a detection component. 6 is a timing chart illustrating a fail-safe process. FIG. 5 is a simplified block diagram showing a fuel pump control device according to a second embodiment. FIG. 2 is a plan view showing a fuel pump control device. The figure which shows an electronic component and a detection component. 9 is a flowchart illustrating a fail-safe process.

  Hereinafter, embodiments for carrying out the present invention will be described using a plurality of embodiments with reference to the drawings. In each embodiment, parts corresponding to the matters described in the preceding embodiments may be denoted by the same reference numerals, or one character may be added to the preceding reference numerals to omit redundant description. When a part of the configuration is described in each embodiment, the other part of the configuration is the same as the previously described embodiment. Not only the combination of the parts specifically described in the respective embodiments, but also the embodiments can be partially combined with each other as long as the combination is not particularly hindered.

(1st Embodiment)
A first embodiment of the present invention will be described with reference to FIGS. The fuel supply system 10 is a system that supplies the fuel in the fuel tank 11 to the engine. The fuel supply system 10 includes a fuel tank 11, a fuel pump 12, a fuel pump control device 13, a delivery pipe, a fuel injection valve, and an electronic control unit (ECU) 15. The fuel pump 12 sucks the fuel in the fuel tank 11 and discharges the fuel toward the delivery pipe. A fuel injection valve that supplies fuel to each cylinder of the engine is connected to the delivery pipe.

  The fuel pump 12 sucks the fuel in the fuel tank 11, increases the pressure of the sucked fuel, and discharges the fuel toward the delivery pipe. A fuel pump controller (Fuel Pump Controller) 13 controls driving of the fuel pump 12. The fuel pump control device 13 is supplied with electric power from the battery 14 and controls electric power supplied to the electric drive type fuel pump 12 installed in the fuel tank 11.

  Specifically, the fuel pump control device 13 controls electric power supplied to the fuel pump 12 by controlling a current value or a voltage value supplied to the fuel pump 12. The amount of fuel discharged from the fuel pump 12 is controlled by controlling the power supplied to the fuel pump 12 by the fuel pump control device 13. The fuel pump control device 13 is electrically connected to the ECU 15 that controls the engine.

  The ECU 15 sends a request signal to the fuel pump control device 13 so that the fuel amount required by the engine can be secured, and supplies the fuel pump 12 to the fuel pump 12 according to the request signal in order to secure the fuel amount required by the engine. The power to be controlled is controlled by the fuel pump control device 13. In this manner, the fuel required by the engine is delivered from the fuel supply system 10 to the engine.

  According to this, the fuel pump 12 may be operated according to the amount of fuel required by the engine, so that the power consumption of the fuel pump 12 can be reduced as much as possible, contributing to power saving of the vehicle. Can be. The ECU 15 grasps the operating state of the engine and the demands of the driver from detection signals of various sensors (not shown). The ECU 15 controls the injection amount and the injection timing of the fuel injection valve based on the grasped driving state and the driver's request, and sends a signal corresponding to the fuel amount required by the engine to the fuel pump control device 13. Send

  The fuel pump control device 13 is mounted on a flange 16 as a cover member, as shown in FIG. The flange 16 is a disc-shaped component that closes a circular hole formed in the ceiling of the fuel tank 11. The flange 16 is formed of a resin material such as POM (polyacetal) having excellent gasoline resistance and electrical insulation.

  The fuel pump control device 13 is mounted on the upper surface side of the flange 16. Therefore, the fuel pump control device 13 is located outside the fuel tank 11. The fuel pump control device 13 is electrically connected to the ECU 15, an external device, the battery 14, and the fuel pump 12.

  A fuel supply pipe 17 is provided in the flange 16 so as to pass therethrough. The fuel supply pipe 17 is a pipe member that supplies fuel discharged from the fuel pump 12 to the engine. As shown in FIG. 1, the fuel supply pipe 17 is formed so as to penetrate the flange 16 in the axial direction. A delivery pipe is connected to an outer end of the fuel supply pipe 17 protruding outside the fuel tank 11, and a fuel hose connected to the fuel pump 12 is connected to an inner end protruding inside the fuel tank 11. ing. Thus, the fuel discharged from the fuel pump 12 can be supplied to the engine.

  The fuel pump 12 is an electrically driven pump, and although not shown, is constituted by an electric motor unit and a pump unit driven by the electric motor unit. The pump section is directly connected to the rotor of the electric motor section, and has an impeller having a plurality of blade grooves on an outer peripheral edge, an arc-shaped boosting flow path covering the blade grooves, and an inlet port and a discharge port communicating with the boosting flow path. And a pump case. The electric motor unit is electrically connected to the fuel pump control device 13, and rotates the rotor and the impeller by the controlled electric power supplied from the fuel pump control device 13.

  As the impeller rotates, the fuel sucked from the suction port is pressurized in the pressurizing flow path and discharged from the discharge port. The discharged fuel passes through the inside of the electric motor unit and is discharged from a fuel discharge port provided at an upper end of the motor unit.

  The fuel pump control device 13 controls electric power supplied to the fuel pump 12 according to an instruction from the ECU 15. The fuel pump control device 13 executes a program stored in a storage medium and controls each unit. The fuel pump control device 13 has at least one arithmetic processing unit (CPU) and a storage medium for storing programs and data. The fuel pump control device 13 is realized by, for example, a microcomputer having a computer-readable storage medium. The storage medium is a non-transitional substantial storage medium that temporarily stores a computer-readable program and data. The storage medium is realized by a semiconductor memory, a magnetic disk, or the like.

  As shown in FIG. 2, the fuel pump control device 13 is configured by mounting a control circuit 21, a drive circuit 22, a sign detection unit 23, and the like on the same printed circuit board 24. The electronic components constituting the control circuit 21, the drive circuit 22, and the sign detection unit 23 are mounted on a printed circuit board 24 by soldering. The electronic components mounted on the printed board 24 are covered with a resin portion 18 made of resin by resin potting. Covering with resin prevents dust, dirt and liquid from adhering. Further, since the printed circuit board 24 and the electronic components are fixed with resin, it is possible to protect the electronic components from vibration. Fuel pump control device 13 has a terminal electrically connected to ECU 15 and battery 14, and a terminal electrically connected to fuel pump 12.

  The drive circuit 22 has three pairs of switching elements connected in series between the battery 14 and the ground, corresponding to the U-phase coil, the V-phase coil, and the W-phase coil of the electric motor unit. The connection points of the switching elements forming a pair are connected to the U-phase current line, the V-phase current line, and the W-phase current line of the load line via the U-phase terminal, the V-phase terminal, and the W-phase terminal. It is connected to the stator coil of each phase of the electric motor unit.

  The control circuit 21 outputs a control signal to each switching element of the drive circuit 22. More specifically, the control circuit 21 switches on a combination of switching elements to be turned on while simultaneously turning on a high-potential-side switching element and a low-potential-side switching element of a predetermined combination among the three pairs of switching elements. Output a control signal as follows. As a result, a drive current is sequentially supplied from the battery 14 to the stator coils of each phase of the electric motor unit, and a rotating magnetic field for rotating the rotor of the electric motor unit is generated.

  The control circuit 21 includes a microcomputer 31, a voltage detection unit 32, and a 5V power supply circuit 33. The microcomputer 31, the voltage detector 32 and the 5V power supply circuit 33 are composed of a plurality of electronic components. The microcomputer 31 generates a control signal to be given to the drive circuit 22 as described above. The 5 V power supply circuit 33 generates a voltage of 5 V from an ignition power supply (IG) and supplies it to the control circuit 21 as an operation voltage. The 5V power supply circuit 33 supplies power to the sign detection unit 23.

  The sign detection unit 23 includes a detection component 23a that is an electronic component having a shorter solder life than the electronic components forming the control circuit 21. In the present embodiment, the detection component 23a employs a constant voltage diode. A voltage of 5V is applied to both ends of the detection component 23a from the 5V power supply circuit 33. When the constant voltage diode serving as the detection component 23a functions normally, a current flows, and thus the voltage at the end of the detection component 23a is 0V. If the solder of the constant voltage diode, which is the detection component 23a, is abnormal and is not properly connected, no current flows, and the voltage at the end of the detection component 23a is 5V.

  The voltage detection unit 32 detects the voltage of the detection component 23a and provides a detection result to the microcomputer 31. Therefore, the microcomputer 31 can determine whether the detection component 23a is normal or abnormal based on the voltage from the voltage detection unit 32.

  The electronic components of the control circuit 21 have lead-like electrodes. In the case of a lead-shaped electrode, the connection position between the printed board 24 and the electronic component is around the electronic component. On the other hand, the detection component 23a has a flat electrode. The flat electrode is provided directly on the back surface of the detection component 23a, and the connection position between the printed board 24 and the detection component 23a is on the back side of the electronic component. Thereby, heat generated by the detection component 23a is easily transmitted to the electrode. Therefore, the solder of the detection component 23a is more likely to be subjected to thermal stress than the electronic component of the control circuit 21 and can be deteriorated more quickly.

  Next, the processing of the control circuit 21 will be described with reference to FIG. The flowchart shown in FIG. 3 is repeatedly executed by the control circuit 21 in a short time. When the ignition is turned on and power is supplied to the control circuit 21, the process is started and the process proceeds to step S1.

  In step S1, the output of the detection component 23a is obtained, and the process proceeds to step S2. The output of the detection component 23a is the voltage of the detection component 23a provided from the voltage detection unit 32. In step S2, it is determined whether or not the detection component 23a is open based on the voltage. If open, the process proceeds to step S4. If not, the process proceeds to step S3. . The open state is a case where the voltage of the detection component 23a is 5 V and an abnormal state where no current flows through the detection component 23a.

  In step S3, since the voltage of the detection component 23a is normal, normal running processing is performed, and the process proceeds to step S5. In step S4, since the voltage of the detection component 23a is abnormal, control is performed to prohibit the operation of the vehicle, and the flow ends. Therefore, if there is an abnormality in the detection component 23a, driving the engine is prohibited even if the ignition is turned on.

  In step S5, the output of the detection component 23a is acquired during the normal running, and the process proceeds to step S6. In step S6, it is determined whether or not the detection component 23a is open based on the voltage. If open, the process proceeds to step S10; otherwise, the process proceeds to step S7. .

  In step S7, since the voltage of the detection component 23a is normal, normal running processing is performed, and the process proceeds to step S8. In step S8, it is determined whether or not the ignition has been turned off. If the ignition has been turned off, the process proceeds to step S9, and if not, the process proceeds to step S5. Thus, the processing from step S5 to step S8 is repeated until the ignition is turned off.

  In step S10, since the voltage of the detection component 23a is abnormal but running, the fail-safe process is performed, and the process proceeds to step S11. In the fail-safe process, a process is performed to prevent the deterioration of the solder of the electronic component of the fuel pump control device 13 from progressing. For example, as shown in FIG. 4, the control is performed so that the supply amount of the fuel pump 12 when the detection component 23a is opened is maintained. By maintaining the supply amount of the fuel pump 12, the load on the fuel pump control device 13 becomes constant, and the temperature change is suppressed. Since the progress of the solder deterioration increases as the temperature change increases, the temperature change is reduced to suppress the progress of the solder deterioration.

  In step S11, it is determined whether or not the ignition has been turned off. If the ignition has been turned off, the process proceeds to step S9, and if not, the process proceeds to step S10. As a result, the fail-safe processing in step S10 is repeated until the ignition is turned off.

  In step S9, since the ignition has been turned off, the operation is stopped and the present flow ends.

  As described above, the control circuit 21 detects an abnormal state different from the conduction state in which the conduction state of the detection component 23a is conduction, and maintains the output of the drive circuit 22 while the engine is running. , So that the output of the drive circuit 22 falls within a predetermined range. Further, the control circuit 21 controls to prohibit driving of the engine when the abnormal state of the detection component 23a is detected and the engine is stopped.

  Next, the fail-safe processing will be further described with reference to FIG. As shown in FIG. 4, in the fuel, the supply amount from the fuel pump 12 is controlled so that there is a surplus amount α than the consumption amount of the engine. The supply amount is proportional to the output of the fuel pump control device 13. The temperature of the fuel pump control device 13 is proportional to the output of the fuel pump control device 13. In other words, if the output of the fuel pump controller 13 fluctuates more, the temperature of the fuel pump controller 13 fluctuates more.

  When the detection component 23a is opened at the time t1, when the supply amount is relatively large, control is performed so as to maintain the supply amount at the time t1. Since there is a margin α originally, even if there is a change in the consumption of the engine, it can be absorbed with the margin α. Unused fuel is returned to the fuel tank 11.

  On the other hand, at time t1, even when the supply amount is relatively small, control is performed so as to maintain the supply amount at time t1. In such a case, the engine consumption may be insufficient even if there is a margin α. Therefore, the fuel pump control device 13 outputs a reduction signal to the engine so as to reduce the fuel consumption. As a result, the engine shifts to the reduction mode in which the output is reduced so that the fuel consumption is reduced.

  When the engine is in the reduction mode, even if the driver steps on the accelerator, for example, the output is limited by the reduction mode. Therefore, when detecting an abnormal state, the control circuit 21 outputs an abnormal signal indicating that the abnormal state has been detected to the ECU 15 which is an external device. Then, the ECU 15 notifies the occupant of the abnormal state by using a warning lamp or the like so that the occupant can recognize the abnormal state. This allows the driver to know that the output of the engine is limited, so that it is possible to eliminate a sense of discomfort during the execution of the reduction mode.

  As described above, the fuel pump control device 13 of the present embodiment has the detection component 23a having a shorter solder life than the electronic components forming the control circuit 21, and the control circuit 21 monitors the energization state of the detection component 23a. ing. Since the detection component 23a has a shorter solder life than the electronic component of the control circuit 21, the solder of the detection component 23a ends its life earlier, and the conduction state becomes an abnormal state different from the conduction state. Therefore, the control circuit 21 can detect that the life of the solder of the electronic component is near before the solder of the electronic component of the control circuit 21 becomes defective.

  Then, the control circuit 21 holds the output of the drive circuit 22 within a predetermined range when the abnormality is detected in the detection component 23a and the engine is being driven. It is not preferable to stop the engine immediately upon detecting an abnormal state, for example, in the case of an engine of a vehicle, because the vehicle suddenly stops during traveling. Therefore, the output of the drive circuit 22 is held so as to be within a predetermined range. Even if an abnormality occurs in the detection component 23a, it does not mean that an abnormality has occurred in the electronic components of the control circuit 21. Therefore, even when the engine is driven, the normal state can be maintained for a while. However, when the temperature change of the control circuit 21 is increased, the deterioration of the solder of the electronic components of the control circuit 21 is accelerated. Thus, the temperature change of the control circuit 21 is reduced by setting the output of the drive circuit 22 within a predetermined range.

  Further, in the present embodiment, the control circuit 21 controls to prohibit driving of the engine when the abnormal state of the detection component 23a is detected and the engine is stopped. As a result, after the detection component 23a is abnormal, the engine is not driven after the engine is stopped. Therefore, it is possible to prevent the occurrence of an abnormality in the control circuit 21 during the operation of the engine.

  Further, in the present embodiment, in the fuel pump control device 13, the control circuit 21 and the like are covered with resin by resin potting. The product temperature rises due to a decrease in heat radiation due to the miniaturization of the fuel pump control device 13 and a decrease in heat radiation due to mounting on the fuel pump 12, and furthermore, the solder life increases due to an increase in solder stress due to resin potting. The degree tends to decrease. However, in the present embodiment, the detection component 23a having a short solder life can quickly detect the sign of the deterioration of the solder and prohibit the driving of the engine before the solder of the control circuit 21 reaches the end of its life. Therefore, even in a mounting environment where the solder life margin decreases, it is possible to avoid engine stalling during traveling.

  Further, in the present embodiment, when detecting an abnormal state, the control circuit 21 outputs an abnormal signal to the ECU 15 indicating that the abnormal state is detected. This allows the occupant to recognize that the fuel pump control device 13 needs to be checked. Therefore, repairs and inspections can be performed with plenty of time.

  Further, in the present embodiment, the control circuit 21 holds the output of the drive circuit 22 within a predetermined range when the abnormal state is detected and the engine is being driven, and controls the engine for fuel consumption. A reduction signal is output to reduce the amount. Thus, fuel consumption by the engine is reduced, and the output of the drive circuit 22 can be maintained within a low range.

  Further, in the present embodiment, the control circuit 21 and the drive circuit 22 are mounted on the flange 16 which is a lid constituting the fuel tank 11. In order to mount the fuel pump on the flange 16, the fuel pump control device 13 is required to be downsized. Therefore, by providing the detection component 23a and performing the fail-safe processing as in the present embodiment, sudden failure of the control circuit 21 and the like can be suppressed.

  Further, in the present embodiment, the electronic component of the control circuit 21 has a lead-shaped electrode, and the detection component 23a has a flat-shaped electrode. This makes the detection component 23a more susceptible to heat than the electronic components of the control circuit 21. Accordingly, the life of the solder of the detection component 23a can be shorter than that of the electronic component of the control circuit 21.

(2nd Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS. The present embodiment is characterized in that the configuration and location of the detection component 23b and the content of the fail-safe processing are different.

  As the detection component 23b, a chip resistor which is a surface mount type resistor is used. Since the chip resistor is surface mounted, the solder is easily subjected to thermal stress, and the life of the solder is shortened. A voltage of 5V is applied to both ends of the detection component 23b from the 5V power supply circuit 33. When the chip resistor serving as the detection component 23b is functioning normally, a current flows, and the voltage at the end of the detection component 23b is 2.5V. If the solder of the chip resistor, which is the detection component 23b, is abnormal and is not properly connected, no current flows, and the voltage at the end of the detection component 23b is 5V.

  The size of the land 28 of the detection component 23b is set to be smaller than that of the electronic component 27 of the control circuit 21, as shown in FIG. Specifically, the width of the land 28 of the detection component 23b is set to be half the width W of the land 28 of the electronic component 27 of the control circuit 21. By reducing the size of the land 28, the deterioration of the solder 29 due to thermal stress is likely to progress, so that the life of the solder 29 can be shorter than that of the electronic component 27 of the control circuit 21. As described above, even in the case of the chip resistor, if there is an abnormality in the conduction state, it can be detected as in the first embodiment.

  As shown in FIG. 6, a plurality of detection components 23b are provided, and are mounted within a predetermined range from a heat generation component 25 which is an electronic component having a large heat generation among the electronic components 27 of the control circuit 21. Since the temperature of the heat generating component 25 changes greatly, the solder deteriorates quickly. Since the temperature change is also large around the heat-generating component 25 in this manner, the deterioration of the solder is accelerated. Therefore, the detecting component 23b is arranged within a predetermined range of the heat generating component 25, for example, within a range of 10 mm from the center of the heat generating component 25. In the example shown in FIG. 6, it is arranged at a position sandwiched between the heat-generating components 25.

  The heat generating component 25 is, for example, a metal-oxide semiconductor (MOS), a shunt resistor, and an electrolytic capacitor. Thereby, the detection component 23b can make the solder deterioration faster than the electronic component 27 of the control circuit 21 and shorten the solder life.

  Further, as shown in FIG. 5, a temperature sensor 26 is mounted on the control circuit 21. The temperature sensor 26 detects the temperature of the control circuit 21 and provides the detected temperature information to the control circuit 21. Then, the control circuit 21 performs the fail-safe process using the temperature information from the temperature sensor 26.

  Next, the fail-safe processing will be described with reference to FIG. The fail safe process shown in FIG. 8 is started when the process proceeds to step S10 in FIG. In other words, the fail-safe processing in step S10 in FIG. 3 is the processing shown in FIG. 8 in the present embodiment.

  In step S21, the open temperature To, which is the temperature at the time of the open detection acquired from the temperature sensor 26, is stored, and the process proceeds to step S22. In step S22, it is determined whether or not the current temperature Tc acquired from the temperature sensor 26 is within a predetermined temperature range of the open temperature To, for example, within a range of ± 5 ° C. If not, the process proceeds to step S24.

  In step S23, since the temperature is within the temperature range, control is performed so as to maintain the current output of the drive circuit 22, and the flow ends.

  In step S24, since the current temperature Tc is not within the temperature range, it is determined whether or not the current temperature Tc is lower than the temperature range. If the current temperature Tc is low, the process proceeds to step S25, and if not, the process proceeds to step S26. When the temperature is low, the current temperature Tc is lower than the open temperature To-5 ° C.

  In step S25, since the temperature is 5 ° C. or more lower than the open temperature To, the output of the drive circuit 22 is controlled to be increased, and this flow ends. When the output of the drive circuit 22 increases, the temperature of the fuel pump control device 13 increases, so that the temperature of the control circuit 21 can be heated within a predetermined temperature range.

  In step S26, since the temperature is higher than the open temperature To by 5 ° C. or more, the output of the drive circuit 22 is controlled to be reduced, and this flow ends. When the output of the drive circuit 22 decreases, the temperature of the fuel pump control device 13 decreases, so that the temperature of the control circuit 21 can be cooled within a predetermined temperature range.

  As described above, the control circuit 21 controls the output of the drive circuit 22 so that the temperature detected by the temperature sensor 26 falls within a predetermined range when the abnormal state is detected and the engine is being driven. . As a result, the temperature change of the electronic component 27 of the control circuit 21 can be reduced, so that the progress of solder deterioration can be suppressed. Further, since the temperature is monitored by the temperature sensor 26, the temperature can be reliably maintained within a predetermined range. Thereby, the deterioration of the solder can be further suppressed.

  In the present embodiment, the fuel pump control device 13 includes a plurality of detection components 23b. Thus, when an abnormality occurs in any one of the detection components 23b, the fail-safe processing is performed, so that the reliability against the life degradation can be further improved. Conversely, fail-safe processing may be performed when an abnormality has occurred in all the detection components 23b. As a result, the fail-safe processing can be performed with more reliable timing.

(Other embodiments)
As described above, the preferred embodiments of the present invention have been described. However, the present invention is not limited to the above-described embodiments, and can be variously modified and implemented without departing from the gist of the present invention.

  The structure of the above-described embodiment is merely an example, and the scope of the present invention is not limited to the scope of the description. The scope of the present invention is shown by the description of the claims, and further includes all modifications within the meaning and scope equivalent to the description of the claims.

  In the first embodiment described above, the type of solder is the same for the control circuit 21 and the detection component 23a, but is not limited to such a configuration. For example, the solder of the detecting component 23a may be more easily deteriorated than the solder of the control circuit 21.

  In each of the above-described embodiments, the detection component 23a is a constant voltage diode and a chip resistor, but is not limited thereto. The detection component 23a may be, for example, a chip capacitor or another electronic component having a high crack rate.

  In the above-described first embodiment, the functions realized by the fuel pump control device 13 may be realized by hardware and software different from those described above, or a combination thereof. The fuel pump control device 13 may communicate with, for example, another control device, and the other control device may execute part or all of the processing. When the fuel pump control device 13 is realized by an electronic circuit, it can be realized by a digital circuit including a large number of logic circuits, or an analog circuit.

DESCRIPTION OF SYMBOLS 10 ... Fuel supply system 11 ... Fuel tank 12 ... Fuel pump 13 ... Fuel pump control device 14 ... Battery 15 ... ECU (external device)
DESCRIPTION OF SYMBOLS 16 ... Flange (lid part) 17 ... Fuel supply pipe 21 ... Control circuit 22 ... Drive circuit 23 ... Sign detection part (detection part) 23a, 23b ... Detection part 24 ... Printed circuit board (board) 25 ... Heat generation part (electronic part) 26 temperature sensor 31 microcomputer 32 voltage detector 33 5V power supply circuit

Claims (11)

A fuel pump control device (13) for controlling driving of a fuel pump (12) for supplying fuel in a fuel tank (11) to an engine,
A drive circuit (22) for supplying power to the fuel pump;
A control circuit (21) for controlling the drive circuit to control electric power supplied to the fuel pump;
A detection unit (23) having detection components (23a, 23b) which are electronic components having a shorter solder life than the electronic components constituting the control circuit;
A temperature sensor (26) for detecting a temperature of the control circuit ,
The control circuit monitors the energization state of the detection component,
The control circuit, when detecting an abnormal state different from the conduction state in which the conduction state of the detection component is conducting, when the engine is running, suppresses the progress of solder deterioration due to temperature changes A fuel pump control device that controls an output of the drive circuit so that a temperature detected by the temperature sensor falls within a predetermined range . The control circuit includes:
The temperature when the abnormal state of the detection component is detected is stored as the open temperature,
Controlling the output of the drive circuit so that the temperature detected by the temperature sensor is within a predetermined range of the open temperature when the engine is being driven when the abnormal state is detected. Item 2. The fuel pump control device according to Item 1. 3. The fuel pump control device according to claim 1, wherein the control circuit is configured to control to prohibit driving of the engine when the engine is stopped when the abnormal state of the detection component is detected. 4. .   4. The fuel according to claim 1, wherein the control circuit outputs, when detecting the abnormal state, an abnormal signal indicating that the abnormal state is detected to an external device (15). 5. Pump control device.   The control circuit is configured to maintain the output of the drive circuit within a predetermined range when the abnormal condition is detected and the engine is being driven, and reduce the fuel consumption of the engine. The fuel pump control device according to any one of claims 1 to 4, wherein the fuel pump control device outputs a reduction signal so as to perform the reduction. The control circuit and the drive circuit are configured by soldering the electronic component and the detection component to a board (24),
The fuel pump control device according to any one of claims 1 to 5, further comprising a resin portion (18) covering the electronic component and the detection component of the board.   The fuel pump control device according to any one of claims 1 to 6, wherein the control circuit and the drive circuit are mounted on a lid (16) constituting the fuel tank. The electronic component of the control circuit has a lead-like electrode,
The fuel pump control device according to claim 1, wherein the detection component has a flat electrode.   The fuel pump control device according to claim 1, wherein a land of the detection component is smaller than a land of the electronic component of the control circuit.   The fuel pump control device according to any one of claims 1 to 9, wherein the detection component is mounted within a predetermined range from a heat-generating component (25) that generates a large amount of heat among the electronic components of the control circuit. .   The fuel pump control device according to claim 1, wherein the detection unit includes a plurality of the detection components.

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