JP2005263080A - In-vehicle power distribution device with battery status detection function - Google Patents

Abstract

A charge / discharge balance of a lead battery is stabilized by surely operating minimum electrical components according to the state of the lead battery.
A current detection unit 51, a voltage detection unit 53, and a central control unit 17 are provided in the in-vehicle power distribution device 10, and the state of the lead battery 5 is determined based on the detection results of the current detection unit 51 and the voltage detection unit 53. Based on the detection result, the relays 11a, 11b,... Are selectively turned on / off according to the priorities stored in advance in the nonvolatile memory 13 so as to stabilize the charge / discharge balance of the lead battery 5. Depending on the state of the lead battery 5, the charge / discharge balance of the lead battery 5 is stabilized by reliably operating the minimum necessary electrical components M 1, M 2, M 3, M 4,.
[Selection] Figure 2

Description

  The present invention relates to an in-vehicle power distribution device with a battery state detection function for detecting a state (remaining battery level or degree of deterioration) of a lead battery mounted on a vehicle.

  As a general power supply system in an automobile, there is one in which a lead battery and an alternator are used in combination. In this case, in starting the automobile, power is supplied from the lead battery to the electrical components of each part.However, if the power consumption of the lead battery is continued, the remaining power of the lead battery decreases, and finally It becomes impossible to supply power to each part of the automobile. Therefore, AC power generation is performed by the rotation of the engine, and the power generated here is charged in a lead battery, thereby enabling long-time power supply to the electrical components of each part.

  Due to the remarkable progress of electronic technology in recent years, various electronic control technologies using electric wires such as drive-by-wire and brake-by-wire have been developed in the field of automobiles. These technologies are intended to electronically control not only the electrical accessories that are attached to automobiles such as audio and air conditioners, but also the main functions related to automobile driving, etc. Many electronic components are used, and computerization and systemization tend to progress.

  Therefore, in automobiles equipped with many electrical components, it is necessary to efficiently supply power to various electrical components from the lead battery and alternator. In particular, the state of the lead battery is accurately detected at that time. Therefore, it is necessary to supply power according to the state.

  By the way, various technologies have been proposed for detecting the state of a lead battery mounted on the vehicle. However, the state of a lead battery in use (running, etc.) that is frequently charged and discharged is accurately determined. It is difficult to detect. For example, as a conventional technique, there is a technique for detecting the remaining battery level by detecting the open terminal voltage of a lead battery. However, since the lead battery is frequently charged and discharged during traveling, the concentration gradient in the solution of the lead battery, etc. As a result, the open terminal voltage is not stable and the remaining battery level cannot be detected accurately.

  Therefore, the problem to be solved by the present invention is that the load is selectively turned on and off so that the state of the lead battery is stabilized while accurately detecting the state of the lead battery even during traveling. It is an object of the present invention to provide an on-vehicle power distribution device with a battery state detection function capable of adjusting the balance of charge and discharge of a battery.

  In order to solve the above-mentioned problem, the invention described in claim 1 is an in-vehicle power distribution device with a battery state detection function that is connected to a lead battery and an alternator and distributes power to various electrical components, Current detection means for detecting a current charged or discharged to the lead battery, voltage detection means for detecting a terminal voltage of the lead battery, and power supply to each electrical component from the lead battery and the alternator individually On / off switching means, and detecting the state of the lead battery based on the detection results of the current detection means and the voltage detection means, and based on the detection result, the opening / closing of the lead battery is stabilized. And a control means for selectively turning on and off the means to adjust the balance of charge and discharge of the lead battery.

  The invention according to claim 2 is the in-vehicle power distribution device with a battery state detection function according to claim 1, wherein the control means detects the current when the charging or discharging of the lead battery is started. Based on the current value of the charge / discharge detected through the means and the amount of change in the terminal voltage before and after the start of the charge / discharge detected through the voltage detection means, the state of the lead battery is determined. Detection is performed, and on-off control of the open / close means is selectively performed based on the detection result so that the state of the lead battery is stabilized.

  A third aspect of the present invention is the in-vehicle power distribution device with a battery state detection function according to the second aspect, wherein the control means is based on the current value of the charge / discharge and the amount of change in the terminal voltage. The internal resistance value of the lead battery is derived, and the state of the lead battery is detected based on the internal resistance value.

  The invention according to claim 4 is the in-vehicle power distribution device with a battery state detection function according to claim 3, wherein the control means derives the internal resistance value obtained when the lead battery is charged. The state of the lead battery is detected on the basis of the charge internal resistance value that is and the discharge internal resistance value that is the internal resistance value derived when the lead battery is discharged.

  A fifth aspect of the present invention is the in-vehicle power distribution device with a battery state detection function according to the fourth aspect, wherein the control means is based on a ratio between the charging internal resistance value and the discharging internal resistance value. The state of the lead battery is detected.

  A sixth aspect of the present invention is the on-vehicle power distribution device with a battery state detection function according to any one of the second to fifth aspects, wherein the control means includes the charge / discharge current value and the terminal voltage. And at least one of the remaining battery level and the degree of deterioration of the lead battery based on the change amount of the lead battery.

  The invention according to claim 7 is the on-vehicle power distribution device with a battery state detection function according to claim 1, wherein the control means is configured to start charging when charging of the lead battery is started. The amount of increase in the terminal voltage of the lead battery per predetermined time is detected via the voltage detection means, the state of the lead battery is detected based on the amount of increase per predetermined time, and based on the detection result, The opening / closing means is selectively on / off controlled so that the state of the lead battery is stable.

  The invention according to claim 8 is the in-vehicle power distribution device with a battery state detection function according to claim 7, wherein the control means is configured such that the remaining battery of the lead battery is based on the amount of increase per predetermined time. At least one of the amount and the degree of deterioration is detected.

  The vehicle-mounted power distribution device with a battery state detection function according to any one of claims 1 to 8, wherein the control means detects the state of the lead battery based on the detection results of the current detection means and the voltage detection means, and the detection result In order to stabilize the charging / discharging balance of the lead battery, the on / off means is selectively controlled to be turned on / off, so that the low-priority electrical components are turned off according to the state of the lead battery, etc. Thus, the charge / discharge balance of the battery can be easily stabilized.

  The in-vehicle power distribution device with a battery state detection function according to claim 2 to claim 6, when charging or discharging of the lead battery is started, the charge / discharge current value and before and after the start of the charge / discharge. Because the state of the lead battery is detected based on the amount of change in the terminal voltage of the lead battery, the state of the lead battery can be detected accurately and easily in accordance with the desired charging / discharging timing even during traveling. Based on this, the balance of charge and discharge of the battery can be appropriately stabilized.

  The vehicle-mounted power distribution device with a battery state detection function according to claim 3 derives the internal resistance value of the lead battery based on the current value of discharge and the amount of change in the terminal voltage, and leads based on the internal resistance value. Since the state of the battery is detected, the state of the lead battery can be detected accurately and easily, and the charge / discharge balance of the battery can be appropriately stabilized based on this.

  The on-vehicle power distribution device with a battery state detection function according to claim 4 is configured such that when the lead battery is charged, the charging internal resistance value, which is an internal resistance value derived when the lead battery is charged, and when the lead battery is discharged. Since the state of the lead battery is detected based on the discharged internal resistance value, which is the derived internal resistance value, the state of the lead battery can be detected accurately and easily, and based on this, the charge / discharge balance of the battery can be determined. It can be properly stabilized.

  Since the vehicle-mounted power distribution device with a battery state detection function according to claim 5 detects the state of the lead battery based on the ratio between the charge internal resistance value and the discharge internal resistance value, the state of the lead battery can be accurately and easily determined. Based on this, it is possible to appropriately stabilize the balance of charge and discharge of the battery.

  The on-vehicle power distribution device with a battery state detection function according to claim 7 and claim 8 is configured to calculate the amount of increase in the terminal voltage of the lead battery per predetermined time accompanying the start of charging when charging of the lead battery is started. Since the state of the lead battery is detected based on the amount of increase per predetermined time detected through the detection means, the state of the lead battery can be accurately and easily adjusted according to the desired discharge timing even during traveling. Based on this, the charge / discharge balance of the battery can be stabilized appropriately.

{First embodiment}
<Configuration>
As shown in FIG. 1, an in-vehicle power distribution device (power distribution unit) 10 with a battery state detection function according to a first embodiment of the present invention includes electrical components M1, M2, M3, M4,. In particular, the state of the lead battery 5 (at least one of the remaining battery level and the degree of deterioration) is accurately detected, and the necessary electrical component (load) M1 is detected based on the detection result. , M2, M3, M4,... Are selectively operated to appropriately stabilize the state of the lead battery 5. In this specification, the remaining battery level indicates the amount of charge that can be discharged with reference to when the lead battery 5 is fully charged, and the degree of deterioration indicates the degree of deterioration of the lead battery 5 due to secular change. .

  FIG. 2 is a circuit block diagram showing the in-vehicle power distribution device 10 with a battery state detection function according to the first embodiment of the present invention. As shown in FIGS. 1 and 2, the on-vehicle power distribution device 10 with a battery state detection function is connected to a regulator 3 that adjusts the generated voltage from the alternator 1 and a lead battery 5, and is connected to various electrical components (loads) M <b> 1. The power supply is distributed to M2, M3, M4,..., And in particular, a central control including a current detection unit (current detection unit) 51, a voltage detection unit (voltage detection unit) 53, a CPU, and the like. Unit (control means) 17.

  As shown in FIG. 2, for example, a three-phase AC generator is applied to the alternator 1. The alternator 1 is disposed around the rotor 21 as a rotor 21 that receives the rotational power of a crankshaft of an automobile by, for example, a V belt. The stator 23 includes a rectifier circuit 25 configured by a diode for rectifying electromotive force in each phase of the stator 23 generated by rotation of the rotor 21.

  The rotor 21 is an electromagnetic coil that generates a magnetic field in response to a field current from the regulator 3. Capacitors 26 for suppressing changes in the field current applied from the regulator 3 are interposed at both ends of the rotor 21.

  For example, the stator 23 is provided with a total of six U-phase, V-phase, and W-phase coils 27 in pairs, and accordingly, the rectifier circuit 25 also has a high voltage corresponding to each coil 27 of the stator 23. A total of 12 diodes are used including the side diode 29a and the low side diode 29b. The generated current output from the cathode of the low-side diode 29b of the stator 23 is connected to relays 11a, 11b,... (Described later) via the plurality of fuses 30 of the in-vehicle power distribution device 10 with a battery state detection function. .

  The regulator 3 is for reducing fluctuations in the power generated by the alternator 1 depending on the engine speed and the like, and includes a first switching element (transistor) 33 connected to one end of the rotor 21 of the alternator 1; A second switching element (transistor) 35 connected to the other end of the rotor 21, and an IC unit 37 that adjusts the field current of the rotor 21 by turning on / off or chopper-controlling both the switching elements 33, 35. . And this IC part 37 adjusts the field current of the rotor 21 based on the regulator adjustment voltage command value D1 given from the regulator control part 15 (after-mentioned) of the vehicle-mounted power distribution device 10 with a battery state detection function. Note that a voltage applied to the fuse 30 in the in-vehicle power distribution device 10 with a battery state detection function is input to the IC unit 37 via the switch 38. The charge warning light 39 of the used instrument panel is turned on.

  As shown in FIG. 2, the on-vehicle power distribution device 10 with a battery state detection function is a relay (open / close) that turns on / off the power supply to various electrical components (loads) M1, M2, M3, M4,. Means) 11a, 11b,..., A nonvolatile memory (storage means) 13 in which information on priorities determined in advance according to various conditions of the vehicle such as the state of the lead battery 5 is stored; The regulator control unit (regulator control unit) 15 that adjusts the voltage supplied from the alternator 1 through the regulator 3, the current detection unit (current detection unit) 51, and the voltage detection unit (voltage detection unit) 53. And the priority order stored in the non-volatile memory 13 while controlling the regulator control unit 15 based on the information obtained in each part of the battery state and the vehicle. Therefore comprising relays 11a, 11b, and the central control unit of the (control means) 17 for controlling the ... off of.

  The relays 11a, 11b,... Are, for example, auxiliary equipment relays 11a that turn on and off the auxiliary equipment M1 that controls functions attached to automobiles such as audio and air conditioners, and brake assist such as anti-lock brakes and air. There are safety relays 11b for turning on and off active safety devices M3 such as a bag system. Each relay 11a, 11b,... Has a contact 41 serving as a switch and an electromagnetic coil 43 for opening and closing the contact by electromagnetic induction. Each of the common ones provided is used.

  The non-volatile memory 13 uses a writable data storage medium such as a flash ROM or an EEPROM, and controls the on / off of each relay 11a, 11b,... And the field current of the rotor 21 of the alternator 1 as described above. The regulator adjustment voltage command value D1 to be instructed for setting by the IC unit 37 of the motor vehicle, for example, the state of the lead battery 5, such as the state of the lead battery 5 (remaining state and deterioration state), and there is an obstacle in the traveling direction, there is a collision. For example, data in an expected pre-crash situation, some abnormal state in which the current, voltage and temperature of a predetermined part of the car show abnormal values, or other normal operation states, etc. It is held in advance in a predetermined format such as a table.

  Here, as an example of a data table in which each relay 11a, 11b,... Is controlled to be turned on / off, priority is given to each electrical component (load) M1, M2, M3, M4,. Applied. For example, as this data table, various conditions such as the state of the lead battery 5 (the remaining amount state and the deterioration state) and the situation where the automobile is about to collide (pre-crash state) are assumed. The auxiliary device relay 11a related to the auxiliary device M1 is turned off, and the safety relay 11b related to the active safety device M3 such as a brake assist such as an antilock brake or an air bag system is turned on. There is a data table of contents.

  The regulator control unit 15 outputs the regulator adjustment voltage command value D1 given from the central control unit 17 to the IC unit 37 of the regulator 3 at a timing instructed by the central control unit 17.

  For example, a shunt resistor or the like is used for the current detection unit 51, and the current detection unit 51 is inserted into a charging / discharging conduction path 54 connected to the positive terminal of the lead battery 5 as shown in FIG. Alternatively, the discharged current is detected. The voltage detection unit 53 detects the terminal voltage of the lead battery 5.

  The central control unit (CPU) 17 is a functional element that is connected to a RAM (not shown) and operates based on a software program stored in advance in the nonvolatile memory 13, and is defined by this software program. As a first function for judging various situations of the automobile and individually turning on / off each of the relays 11a, 11b,... According to the situation, and a regulator adjustment voltage command value read from the nonvolatile memory 13. There is a second function of selecting D1 and outputting the selected regulator adjustment voltage command value D1 to the regulator 3 via the regulator control unit 15.

  The first function of the central control unit 17 recognizes a current value I input from a current detection unit (current detection means) 51 installed between the lead battery 5 and each fuse 30, as shown in FIG. A voltage value V commonly applied to each relay 11a, 11b,... Through each fuse 30 is recognized based on detection by a voltage detection unit (voltage detection means) 53, and a predetermined surface such as a housing surface of the lead battery 5 is identified. The temperature of the part is recognized based on the detection by the temperature sensor 55, and driving of each electrical component (load) M1, M2, M3, M4,... Of the automobile obtained from the multiplex communication line 57 of the in-vehicle LAN through the communication device. The situation is recognized, and the relays 11a, 11b,... Are individually controlled on and off based on the recognition results (current recognition result, voltage recognition result, temperature recognition result, and automobile situation recognition result).

  Here, in the first function, when the respective relays 11a, 11b,... Are controlled on and off based on the current recognition result, the current value I detected by the current detection unit 51 exceeds the predetermined reference current value. In this case, the current value I is determined as an overcurrent, and some or all of the relays 11a, 11b,... Are temporarily disconnected, or the current value I is reduced by chopper control.

  In the first function, when the relays 11a, 11b,... Are turned on / off based on the current recognition result, the central control unit 17 detects the current when charging or discharging the lead battery 5 is started. Based on the current value of the charge / discharge detected through the unit 51 and the amount of change in the terminal voltage before and after the start of the charge / discharge detected through the voltage detection unit 53, the remaining battery level of the lead battery 5 is determined. Detect amount and degree of degradation. Detection by the central control unit 17 of the start of charging or discharging of the lead battery 5 is performed based on, for example, detection of a charging / discharging current by the current detection unit 51.

  Here, the principle of the state detection of the lead battery 5 according to the present embodiment will be described.

  FIG. 4 is a graph showing a result of measuring a change state of the terminal voltage when charging / discharging the lead battery at various current values. In the test of FIG. 4, the open terminal voltage (remaining battery level) is varied in various ways with respect to the lead battery 5 in which the open terminal voltage is stable at a value corresponding to the remaining battery level. The terminal voltage immediately after the start of each charge / discharge (for example, 100 ms after the start of charge / discharge (charging / discharging is continuing)) was measured. The horizontal axis of the graph of FIG. 4 corresponds to the open terminal voltage, and the vertical axis corresponds to the terminal voltage immediately after the start of charging / discharging. Each series of graphs G1a to G1c in FIG. 4 shows the terminal voltage measurement results after a minute time (for example, after 100 ms) from the start of charging when 5A, 10A, and 15A are charged at each open terminal voltage. Each series of the graphs G2a to G2c corresponds to the measurement result of the terminal voltage after a minute time (for example, after 100 ms) from the start of charging when discharging 5A, 10A, and 15A at each open terminal voltage. It corresponds. The series of graph G3 shows the state when charging / discharging is not performed (when there is no change in terminal voltage) as a reference.

  From the test result of FIG. 4, in a state where the open terminal voltage is relatively high (a state where the remaining battery level is large) (for example, a region indicated by A1 in FIG. 4), the higher the open terminal voltage (the higher the remaining battery level). It turns out that the variation | change_quantity of the terminal voltage of the lead battery 5 with respect to charging / discharging (especially charge) is large. From this, it can be seen that at least the remaining battery level of the lead battery 5 can be estimated based on the current value during charging and discharging and the amount of change in the terminal voltage.

  Moreover, these quantity values are greatly related to the deterioration degree of the lead battery 5 as described below, and the deterioration degree of the lead battery 5 can be estimated based on these quantity values. FIG. 5 is a graph comparing the amount of change in terminal voltage associated with charging / discharging for two types of lead batteries having different degrees of deterioration. More specifically, the graph G11 in FIG. 5 shows the amount of change in the terminal voltage during charging / discharging by charging / discharging the new lead battery 5 with about 80% remaining battery power while changing the current value. The graph G12 shows the amount of change in the terminal voltage during charging / discharging by charging / discharging the lead battery 5 with a remaining battery level of approximately 75% while changing the current value. The measurement result is shown. From the graph of FIG. 5, it can be seen that if the remaining battery level is the same level, the amount of change in the terminal voltage with respect to charge and discharge at each level is greater in the deteriorated product than in the new product.

In the present embodiment, in order to obtain a more advantageous quantity index for estimating the remaining battery level and the degree of deterioration of the lead battery 5, the central control unit 17 is provided with the current value during charging and discharging and the amount of change in the terminal voltage. Based on this, the internal resistance value of the lead battery 5 at that time is derived. The derivation of the internal resistance value Rin is based on Ohm's law using, for example, the current value I during charge / discharge and the terminal voltage change dV.
Rin = dV / I
The following relational expression can be used.

  FIG. 6 is a graph showing the relationship between the open terminal voltage and the derived internal resistance value when charge / discharge of a predetermined current value is performed on a lead battery (new lead battery), and the horizontal axis of the graph is Corresponding to the open terminal voltage, the vertical axis corresponds to the internal resistance value. More specifically, a graph G21 in FIG. 6 shows an internal resistance value (charging internal resistance value) derived based on a measurement result when 10A is charged at each different open-circuit voltage, and the graph G22 These show the internal resistance value (discharge internal resistance value) derived based on the measurement result when discharging 10 A at different open terminal voltages. From the graph of FIG. 6, especially in a relatively high open terminal voltage state, there is a strong correlation between the internal resistance value (particularly, the charge internal resistance value derived during charging) and the open terminal voltage (remaining battery level). I understand that.

  Further, since the internal resistance value is a very effective quantity index for evaluating the degree of deterioration of the lead battery 5 (generally, the internal resistance value increases as the deterioration progresses), and therefore, this derived internal resistance value is used. The degree of deterioration of the lead battery 5 can be estimated. Therefore, for example, the central control unit 17 can detect the degree of deterioration of the lead battery 5 based on one or both of the derived charge internal resistance value and discharge internal resistance value. In this case, for example, when a predetermined threshold level is provided and it is detected that the charging internal resistance value or the discharging internal resistance value exceeds the threshold level, the central control unit 17 is notified of the deterioration of the lead battery 5. A notification signal may be output.

  Further, in the present embodiment, in order to obtain a more effective quantity index for detecting the state of the lead battery 5, the state detection is performed by calculating the ratio between the charging internal resistance value and the discharging internal resistance value acquired at timings close to each other. I am trying to use it. FIG. 7 is a graph showing a ratio value between a charge internal resistance value and a discharge internal resistance value acquired when charging / discharging a lead battery (new lead battery) with a predetermined current value at different open terminal voltages. is there. More specifically, the value of the ratio between the charging internal resistance value and the discharging internal resistance value in FIG. 7 is obtained by charging and discharging a predetermined current value (for example, 10 A) at approximate timings at different open terminal voltages. This is performed on the lead battery 5 and obtained by dividing the charge internal resistance value by the discharge internal resistance value by acquiring the charge internal resistance value and the discharge internal resistance value by the above-described method at the time of charge / discharge. Yes. From the graph of FIG. 7, in the state where the open terminal voltage is relatively high (the battery remaining amount is relatively large), the ratio between the two internal resistance values and the open terminal voltage (battery remaining amount) are close to a proportional relationship. It can be seen that the remaining battery level can be estimated from the ratio between the two internal resistance values.

  Therefore, in the present embodiment, when the lead battery 5 is charged and discharged at close timings, the central control unit 17 detects the charge / discharge via the current detection unit 51 and is based on the charge. A charge internal resistance value and a discharge internal resistance value based on discharge are acquired. As described above, the charge internal resistance value and the discharge internal resistance value are the charge / discharge current value detected through the current detection unit 51 during the charge / discharge and the charge / discharge detection through the voltage detection unit 53. Based on the amount of change in the terminal voltage before and after the start of charge (for example, the difference between the terminal voltage before the start of charge / discharge and the terminal voltage 100 ms after the start of charge / discharge) Is obtained and obtained. Then, the central control unit 17 derives a ratio between the internal resistance values (for example, a value obtained by dividing the charging internal resistance value by the discharge internal resistance value), and based on the derived ratio between the internal resistance values, The state of the lead battery 5 (particularly, the remaining battery level) is detected.

  Here, the detection of the remaining battery level based on the ratio between the two internal resistance values is, for example, data (data table or the like) indicating a correspondence relationship between the internal resistance value and the remaining battery amount obtained in advance by a test. Can be registered in the storage unit of the central control unit 17 and the correspondence relationship data can be used. In this case, the central control unit 17 may display information on the detected remaining battery level via a predetermined display unit (not shown).

  In the first function, according to the state of the lead battery 5, each relay 11a, so as to stabilize the state of the lead battery 5 based on the data table stored in advance in the nonvolatile memory 13 11b,... Are on / off controlled to adjust the charge / discharge balance of the lead battery 5. Here, when the electrical components (loads) M1, M2, M3, M4,... Are turned off depending on the state of the lead battery 5, for example, when the remaining amount of the lead battery 5 is small, many unnecessary electrical components. (Load) When M1, M2, M3, M4,... Are turned off and the lead battery 5 is regenerated, or when the lead battery 5 is deteriorating, charging is performed according to the deterioration status of the lead battery 5. When adjusting the voltage for switching the discharge, power consumption of appropriate electrical components (loads) M1, M2, M3, M4,... Is determined, and electrical components (loads) M1, M2, M3, M4 corresponding to the power consumption are determined. ,... Are on / off controlled. In this case, for example, the remaining amount of the lead battery 5 is maintained within a predetermined remaining amount range of about 98% with respect to the full charge (100%) so that the lead battery 5 is not overcharged. ing. When the lead battery 5 deteriorates, the voltage in the fully charged state also changes. For example, the remaining amount of the lead battery 5 is predetermined with respect to the fully charged (100%) with reference to the changed voltage. It is designed to be maintained within the remaining capacity range.

  In the first function, the relays 11a, 11b,... Are controlled to be turned on / off based on only the voltage recognition result. In this case, when the voltage value V detected by the voltage detection unit 53 exceeds a predetermined reference maximum voltage value, some or all of the relays 11a, 11b,... To reduce the voltage value V. On the other hand, when the voltage value V detected by the voltage detection unit 53 is below a predetermined reference minimum voltage value, the voltage from the regulator 3 is increased through the second function.

  Further, in the first function, when the relays 11a, 11b,... Are turned on / off based on the temperature recognition result, the temperature detected by the temperature sensor 55 exceeds the predetermined reference temperature value. It is determined that the part where the sensor 55 is installed is overheated, and a part or all of the relays 11a, 11b,... Are temporarily disconnected or chopper control is performed to reduce the temperature.

  Furthermore, in the first function, when the relays 11a, 11b,... Are controlled on and off based on the vehicle status recognition result obtained from the multiplex communication line 57, the data table held in the nonvolatile memory 13 , Etc., and on / off control of the relays 11a, 11b,. That is, in this data table or the like, priorities are given to the respective electrical components (loads) M1, M2, M3, M4,... According to the safety level of the automobile, and based on this, each priority is given to the situation of the automobile. The electrical components (loads) M1, M2, M3, M4,.

  For example, a vehicle periphery visual recognition device or a laser using a CCD is recognized based on a signal given through a multiplex communication line 57 from a vehicle speed sensor, a GPS receiver, or the like, and the vehicle travels above a certain speed. When an obstacle existing in the traveling direction of the vehicle is detected based on a signal given from the used distance measuring device or the like through the multiplex communication line 57, the vehicle is in a state of pre-crash (pre-crash state). Based on the determination result, the auxiliary device relays 11a related to the auxiliary devices M1... Such as the audio and the air conditioner are turned off (power supply cut-off state), and the safety relay 11b is turned on and turned off. Turn on (power supply enabled) the active safety device M3 ... such as brake assist such as lock brake and airbag system To supply concentrate to the power supply from the lead battery 5 or regulator 3 to the active safety equipment M3 .... As a result, immediately before the collision of the automobile, power can be supplied to the active safety devices M3, which are important for safety, so that the active safety devices M3 can be reliably operated.

  In the second function of the central control unit 17, as described above, the regulator adjustment voltage command value D1 is read from the nonvolatile memory 13 and selected according to the situation of the automobile, and the selected regulator adjustment voltage command value D1 is used as the regulator. This is output to the regulator 3 via the control unit 15. As the regulator adjustment voltage command value D1, in principle, the field current of the rotor 21 is determined in advance so as to give the maximum value of the generated voltage generated by the alternator 1 to the on-vehicle power distribution device 10 with the battery state detection function. The value for the maximum value is selected. In particular, in the first function, when the voltage value V detected by the voltage detection unit 53 is lower than a predetermined reference minimum voltage value, the field current of the rotor 21 of the regulator 3 is set to a predetermined maximum value. Is selected as the regulator adjustment voltage command value D1. On the other hand, in the first function, when the voltage value V detected by the voltage detection unit 53 exceeds a predetermined reference maximum voltage value, the regulator adjustment voltage for reducing the field current of the rotor 21 of the regulator 3. The command value D1 is selected. Then, the selected regulator adjustment voltage command value D1 is output to the IC unit 37 of the regulator 3 through the regulator control unit 15.

  Note that reference numeral 59 in FIG. 2 denotes a starter switch unit, and the starter motor 61 is turned on and off by an electromagnetic relay 63.

<Operation>
The operation of the in-vehicle power distribution device 10 with the battery state detection function configured as described above will be described. As shown in FIGS. 1 and 2, the on-vehicle power distribution device 10 with a battery state detection function is connected to a regulator 3 that adjusts the generated voltage from the alternator 1 and a lead battery 5, and is connected to various electrical components (loads) M <b> 1. When distributing power to M2, M3, M4,..., Priorities are determined in advance according to various conditions of the vehicle such as the state of the lead battery 5 (remaining state and deterioration state) and pre-crash. In addition, in order to stabilize the state of the lead battery 5 in various vehicle situations, the electrical components (loads) M1, M2, M3, M4,. Thus, the balance of charge and discharge of the lead battery 5 is adjusted, and necessary electrical components (loads) M1, M2, M3, M4,. Here, when the electrical components (loads) M1, M2, M3, M4,... Are turned off depending on the state of the lead battery 5, for example, when the remaining amount of the lead battery 5 is small, many unnecessary electrical components. (Load) When M1, M2, M3, M4,... Are turned off and the lead battery 5 is regenerated, or when the lead battery 5 is deteriorating, charging is performed according to the deterioration status of the lead battery 5. When adjusting the voltage for switching discharge, the power consumption of appropriate electrical components (loads) M1, M2, M3, M4,... Is determined, and electrical components (loads) M1, M2, M3, M4 corresponding to the power consumption are determined. ,... Are controlled on and off. In this case, for example, the remaining amount of the lead battery 5 is maintained within a predetermined remaining amount range of about 98% with respect to the full charge (100%) so that the lead battery 5 is not overcharged. . When the lead battery 5 deteriorates, the voltage in the fully charged state also changes. For example, the remaining amount of the lead battery 5 is predetermined with respect to the fully charged (100%) with reference to the changed voltage. Maintain within the remaining capacity range.

  First, the central control unit 17 of the in-vehicle power distribution device 10 with the battery state detection function reads the regulator adjustment voltage command value D1 from the nonvolatile memory 13 and selects it according to the situation of the vehicle, and this selected regulator adjustment voltage command value D1. Is output to the regulator 3 via the regulator control unit 15, and in principle, by adjusting the regulator adjustment voltage command value D1, the maximum value of the generated voltage generated by the alternator 1 is mounted on the vehicle with a battery state detection function. Control is performed so that the power is distributed to the power distribution device 10. Then, not only necessary electrical components but also unnecessary electrical components are turned on as much as possible in the short term to increase the generated power generated by the alternator 1. In this case, the IC unit 37 of the regulator 3 sets the field current of the rotor 21 of the alternator 1 to a predetermined maximum according to the regulator adjustment voltage command value D1 given from the in-vehicle power distribution device 10 with the battery state detection function. As a general rule, the generated voltage generated by the alternator 1 and applied from the regulator 3 to the in-vehicle power distribution device 10 with the battery state detection function is always set to a predetermined maximum value.

  Here, in FIG. 2, when the current value I input from the current detecting unit 51 such as a shunt resistor interposed between the lead battery 5 and each fuse 30 exceeds a predetermined reference current value. The central control unit 17 determines that the current value I is an overcurrent and temporarily disconnects some or all of the relays 11a, 11b,... Or reduces the current value I by chopper control.

  And when the charge or discharge with respect to the lead battery 5 is started, the central control part 17 is the charging / discharging electric current value, and the variation | change_quantity of the terminal voltage of the lead battery 5 before and after the start of the charging / discharging (FIG. Based on 5), the state of the lead battery 5 is detected. Specifically, the central control unit 17 determines whether or not the charge resistance is an internal resistance value derived when the lead battery 5 is charged based on the charge / discharge current value and the change amount of the terminal voltage (FIG. 5). A ratio (FIG. 7) between the resistance value and the discharge internal resistance value, which is the internal resistance value derived when the lead battery 5 is discharged, is obtained, and the state of the lead battery 5 is detected based on this ratio. .

  Thereby, even if it is driving | running | working, according to the timing of charging / discharging desired, the state (a residual amount state, a degradation state, etc.) of the lead battery 5 can be detected correctly and easily.

  When the central control unit 17 determines that the remaining amount of the lead battery 5 is reduced based on the state of the lead battery 5, for example, the central control unit 17 switches some or all of the relays 11 a, 11 b,. Cutting temporarily or reducing the current value I by chopper control.

  When the voltage value V commonly applied to the relays 11a, 11b,... Through the fuses 30 exceeds a predetermined reference maximum voltage value, the central control unit 17 determines some or all of the relays. 11a, 11b,... Are temporarily disconnected, or the voltage value V is reduced by chopper control. Further, the central control unit 17 adjusts the field adjustment current of the rotor 21 of the alternator 1 by adjusting the regulator adjustment voltage command value D1, and the generated voltage supplied from the regulator 3 to the vehicle-mounted power distribution device 10 with the battery state detection function. Adjust.

  On the contrary, when the voltage value V detected by the voltage detection unit 53 is lower than the predetermined reference maximum / minimum voltage value, the central control unit 17 determines the field current of the rotor 21 of the regulator 3 in advance. A value for setting the maximum value is selected as the regulator adjustment voltage command value D1, and this regulator adjustment voltage command value D1 is output to the IC unit 37 of the regulator 3 through the regulator control unit 15. At this time, the IC unit 37 of the regulator 3 adjusts the field current of the rotor 21 based on the regulator adjustment voltage command value D1 given from the in-vehicle power distribution device 10 with the battery state detection function. In principle, the field current of the rotor 21 is set to a predetermined maximum value, so that the generated voltage generated by the alternator 1 and applied from the regulator 3 to the vehicle-mounted power distribution device 10 with the battery state detection function is always predetermined in principle. Set to the maximum value given.

  When the temperature detected by the temperature sensor 55 exceeds a predetermined reference temperature value, the central control unit 17 determines that the part where the temperature sensor 55 is installed is in an overheated state, All the relays 11a, 11b,... Are temporarily disconnected or the chopper control is performed to reduce the temperature.

  Further, the central control unit 17 performs on / off control of the relays 11a, 11b,... Based on the vehicle state recognition result obtained from the multiplex communication line 57.

  For example, a vehicle periphery visual recognition device or a laser using a CCD is recognized based on a signal given through a multiplex communication line 57 from a vehicle speed sensor, a GPS receiver, or the like, and the vehicle travels above a certain speed. When an obstacle existing in the traveling direction of the vehicle is detected based on a signal given through the multiplex communication line 57 from the used distance measuring device or the like, the central control unit 17 detects the situation (pre- Crash situation) is determined. Then, based on the determination result, the auxiliary device relays 11a related to the auxiliary devices M1... Such as audio and air conditioner are turned off, and the safety relay 11b is turned on to brake assist such as an anti-lock brake. The active safety device M3... Such as the air bag system is turned on, and the power from the lead battery 5 or the regulator 3 is concentrated and supplied to the active safety device M3. As a result, immediately before the collision of the automobile, power can be supplied to the active safety devices M3, which are important for safety, so that the active safety devices M3 can be reliably operated.

  Thus, in this embodiment, when charge or discharge to the lead battery 5 is started, the current value of the charge / discharge and the amount of change in the terminal voltage of the lead battery 5 before and after the start of the charge / discharge ( Since the state of the lead battery 5 is detected based on FIG. 5), the state of the lead battery 5 can be accurately and easily detected by the central control unit 17. Therefore, on the basis of the accurately detected state of the lead battery 5, the relays 11a, 11b,... Are controlled on and off to adjust the balance of charge and discharge of the lead battery 5 so as to stabilize the state of the lead battery 5. It becomes possible to turn on the necessary electrical components, and the power distribution to each electrical component can be appropriately performed. And since the central control part 17 which carries out on-off control of the electric current detection part 51, the voltage detection part 53, and each relay 11a, 11b, ... is built in the in-vehicle power distribution device 10, it only installs the in-vehicle power distribution device 10. Thus, the charge / discharge balance of the lead battery 5 can be controlled so as to stabilize the state of the lead battery 5, which is convenient for handling when mounted on an automobile or the like.

  In this embodiment, priority is given to various electrical components M1, M2, M3, M4,... According to various conditions of the automobile such as the state of the lead battery 5 (remaining state and deterioration state) and pre-crash. The order is determined in advance, and the charging / discharging of the lead battery 5 is performed by turning off the low-priority electrical components M1, M2, M3, M4,. As much as possible, the necessary electrical components (loads) M1, M2, M3, M4,... Can be operated reliably. Even if you do not use large and heavyweight products that take into account special situations, you can reliably and efficiently operate only the minimum electrical components M1, M2, M3, M4, etc. according to the situation of the car. Is possible It is. Therefore, in a vehicle equipped with many electrical components, the increase in size and weight of the lead battery 5 and the alternator 1 can be mitigated. As a result, since a high voltage electric wire is not required, the increase in size and weight of the wire harness connected thereto can be mitigated.

  Further, in order to stabilize the charge / discharge balance of the lead battery 5 when the active safety device M3 does not operate, not only necessary electrical components but also unnecessary electrical components are turned on as much as possible in the short term to generate the alternator 1 By increasing the generated power generated in step S3, when the active safety device M3... Operates, power can be reliably supplied to the active safety device M3.

{Second Embodiment}
An in-vehicle power distribution device (power distribution unit) 10 with a battery state detection function according to a second embodiment of the present invention includes a current detection unit (current detection unit) 51 and a voltage detection unit (voltage detection unit). 53 and a central control unit 17 constituted by a CPU or the like, and is a diagram that detects the state (at least one of the remaining battery level and the degree of deterioration) of the lead battery 5 mounted on the vehicle. It is the same as that of 1st Embodiment shown in FIGS.

  However, in the first embodiment, when the central control unit 17 starts charging or discharging the lead battery 5, the current value and voltage of the charge / discharge detected via the current detection unit 51 are as follows. In contrast to detecting the remaining battery level and the degree of deterioration of the lead battery 5 based on the amount of change in the terminal voltage before and after the start of the charge / discharge detected via the detection unit 53, this second In the embodiment, the central control unit 17 detects, through the voltage detection unit 53, the amount of increase in the terminal voltage of the lead battery 5 accompanying the start of charging when the charging of the lead battery 5 is started. The state of the lead battery 5 is detected based on the amount of increase per predetermined time. The detection by the central control unit 17 of the start of charging the lead battery 5 is performed based on, for example, detection of the charging current by the current detection unit 51.

  Next, the principle of state detection of the lead battery 5 according to the present embodiment will be described.

  FIG. 8 is a waveform graph showing a result of measuring a change in terminal voltage with time when a lead battery in various states is charged with a predetermined current value. In the test of FIG. 8, as shown by the waveform graph G1, the lead battery 5 in a different state was charged with a predetermined current (for example, 10A). Each waveform graph G2 to G4 in FIG. 8 shows a new lead battery 5 having an open terminal voltage (OCV) of 13.0 V (a state where the remaining battery level is almost fully charged) and an open terminal voltage of 11.7 V (battery). The terminal when the waveform graph G1 is charged to a new lead battery 5 having a remaining amount of about 20% with reference to a full charge) and a lead battery 5 having a degraded open terminal voltage of 12.5V The test results are shown for the change with time of voltage. Note that the test of FIG. 8 is performed by charging the graph G1 in a state where the open terminal voltage of the lead battery 5 is stable at a value corresponding to the remaining battery level.

  From the test results of FIG. 8, even when the same current value is charged according to the state of the lead battery 5 (remaining battery level, deterioration degree), the amount of change in terminal voltage per predetermined time (or the terminal) that accompanies charging It can be seen that the voltage change rates (gradients M1 to M3) are different. As a result, it is understood that the state of the lead battery 5 at that time can be detected by measuring the amount of change in the terminal voltage caused by the charging per predetermined time.

  FIG. 9 is a graph showing the rising speed of the terminal voltage obtained when a new lead battery is charged with a predetermined current value at different open terminal voltages, the horizontal axis corresponding to the open terminal voltage, The axis corresponds to the rising speed of the terminal voltage. In the test of FIG. 9, a new lead battery 5 is charged with a predetermined current value (for example, 10 A) by changing the open terminal voltage (remaining battery level) in various ways, and each charge starts. The rising speed of the terminal voltage was measured. The terminal voltage rise rate is measured, for example, by the terminal voltage (start voltage) at the start of charging (time t0) and the terminal voltage (rise voltage) at the time when a predetermined time (for example, 100 ms) has elapsed from the start of charging. Is measured, a rise amount that is a difference between the start voltage and the rise voltage is derived, and the rise amount is divided by the predetermined time (for example, 100 ms).

  From the test results of FIG. 9, it can be seen that in a state where the open terminal voltage is relatively high (a state where the remaining battery level is large), the terminal voltage rise rate increases as the open terminal voltage increases (the remaining battery level increases). From this, it can be seen that at least for a new lead battery 5, if the rate of increase in the terminal voltage accompanying the start of charging is measured, the remaining battery level can be estimated based on the measurement result. Further, as a result of the test, it is known that when the open terminal voltage is the same, the lead battery 5 that has deteriorated has a higher terminal voltage increase rate at the start of charging at a predetermined current value. For example, when the open terminal voltage is 12.5 V, the rising speed of the terminal voltage accompanying the start of charging the predetermined current value is about 7 (V / s) in the new lead battery 5 as shown in the graph of FIG. On the other hand, it becomes about 38 (V / s) in the lead battery 5 of a deteriorated product.

  From this test result, for example, for various lead batteries 5 with different states (remaining battery level and deterioration level), the deterioration level of the lead battery 5, the remaining battery level, and the terminal voltage increase accompanying the start of charging with a predetermined current amount If the degree of deterioration of the lead battery 5 is known by another method by deriving the relationship with the speed by a test and registering the data indicating the relationship in the central control unit 17, the central control unit 17 Based on the relationship between the registered deterioration level, the remaining battery level, and the terminal voltage increase rate, the remaining battery level is calculated from the deterioration level obtained by another method and the terminal voltage increase rate associated with the start of charging at a predetermined current value. It is possible to guess the amount. Alternatively, if the remaining charge amount of the lead battery 5 is known by another method, the central control unit 17 determines whether another charge level is different based on the relationship between the registered deterioration degree, the remaining battery amount, and the terminal voltage increase rate. It is possible to estimate the degree of deterioration from the remaining charge amount obtained by the method and the rising speed of the terminal voltage accompanying the start of charging at a predetermined current value.

  As a specific example, for example, a case will be described in which the degree of deterioration of the lead battery 5 is detected based on the rising speed of the terminal voltage accompanying the start of charging when fully charged. First, as a preparation, the relationship between the degree of deterioration of the lead battery 5 at the time of full charge and the terminal voltage increase rate at the start of charging at a predetermined current value is obtained by a test, and the relationship is registered in the central control unit 17 in advance. Keep it. When the central control unit 17 detects that the lead battery 5 has been charged via the current detection unit 51 in a state where it is detected that the lead battery 5 is fully charged. In addition, the rising speed of the terminal voltage accompanying the start of charging is detected via the voltage detection unit 53, and the degree of deterioration is detected from the detected rising speed of the terminal voltage, and the degree of deterioration registered in advance and the rising speed of the terminal voltage are Derived based on the relationship. The central control unit 17 detects that the lead battery 5 is in a fully charged state, for example, through the current detection unit 51, the degree of decrease in charging current when a predetermined level of charging voltage is applied to the lead battery 5. This can be done by detecting.

  In addition, as a specific determination method for detecting the deterioration degree, for example, a predetermined threshold level related to the deterioration degree is provided, and it is detected that the rising speed of the terminal voltage accompanying the detected charging start exceeds the threshold level. In this case, the central control unit 17 may output a notification signal for notifying the deterioration of the lead battery 5.

  Based on the accurately detected state of the lead battery 5, the central control unit 17 performs on / off control of the relays 11a, 11b,... So that the charge / discharge balance of the lead battery 5 is stabilized. The point which turns on centering on goods is the same as that of 1st Embodiment shown in FIGS. 1-3.

  Also according to this embodiment, it is possible to appropriately distribute power to each electrical component. And since the central control part 17 which carries out on-off control of the electric current detection part 51, the voltage detection part 53, and each relay 11a, 11b, ... is built in the in-vehicle power distribution device 10, it only installs the in-vehicle power distribution device 10. Since the charge / discharge balance of the lead battery 5 can be controlled to be stable according to the state of the lead battery 5, the point that is convenient for its handling when mounted on an automobile is also shown in FIGS. This is the same as the embodiment.

  In the present embodiment, the lead battery 5 is detected to be charged at a predetermined current value, and the state of the lead battery 5 is detected at that timing, but the central controller 7 includes an alternator and a regulator. The central control unit 17 may positively control the timing of charging the lead battery 5 that can be used for state detection by controlling the charging of the lead battery 5 by controlling the above and the like.

  Thus, according to the present embodiment, when charging of the lead battery 5 with a predetermined current value is started, the amount of increase (increase speed) per predetermined time of the terminal voltage of the lead battery 5 accompanying the start of charging is set to the voltage. Since the state of the lead battery 5 (at least one of the remaining battery level and the degree of deterioration) is detected on the basis of the speed of increase detected by the detection unit 53, the desired discharge timing can be obtained even during traveling. In addition, the state of the lead battery 5 can be accurately and easily detected, and based on the detection result, the charge / discharge balance of the lead battery 5 can be appropriately controlled.

It is a general | schematic block diagram which shows the vehicle-mounted power distribution device with a battery state detection function which concerns on the 1st Embodiment of this invention, a lead battery, an alternator, and a regulator. It is a block diagram which shows the vehicle-mounted power distribution device with a battery state detection function which concerns on the 1st Embodiment of this invention. It is a block diagram which shows a part of vehicle-mounted power distribution device with a battery state detection function which concerns on the 1st Embodiment of this invention. It is a graph which shows the result of having measured the change state of the terminal voltage at the time of charging / discharging with various electric current values with respect to a lead battery. It is the graph which compared the variation | change_quantity of the terminal voltage accompanying charging / discharging about two types of lead batteries from which a deterioration degree differs. It is a graph which shows the relationship between the open terminal voltage at the time of charging / discharging of a predetermined electric current value with respect to a lead battery, and the derived | led-out internal resistance value. It is a graph which shows the value of the ratio of the charge internal resistance value acquired when charging / discharging a lead battery with a predetermined current value in a different open terminal voltage, and a discharge internal resistance value. It is a waveform graph which shows the result of having measured the time-dependent change of the terminal voltage at the time of charging with the predetermined electric current value with respect to the lead battery of various states. It is a graph which shows the rising speed of the terminal voltage acquired when charging a new lead battery with a predetermined current value at different open terminal voltages.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Alternator 3 Regulator 5 Lead battery M1, M2, M3, M4, ... Electrical component 10 In-vehicle power distribution device 11a, 11b, ... with battery state detection function Relay 13 Non-volatile memory 15 Regulator control unit 17 Central control unit 21 Rotor 23 Stator 25 rectifier circuit 30 fuse 33, 35 switching element 37 IC unit 51 current detection unit 53 voltage detection unit 55 temperature sensor 57 multiplex communication line

Claims (8)

An in-vehicle power distribution device with a battery state detection function that is connected to a lead battery and an alternator and distributes power to various electrical components,
Current detecting means for detecting current charged or discharged with respect to the lead battery;
Voltage detecting means for detecting a terminal voltage of the lead battery;
Opening and closing means for individually turning on and off the power supply to each electrical component from the lead battery and the alternator,
Based on the detection results of the current detection means and the voltage detection means, the state of the lead battery is detected, and on the basis of the detection result, the opening / closing means is selectively turned on / off so that the state of the lead battery is stabilized. A vehicle-mounted power distribution device with a battery state detection function, comprising control means for controlling and adjusting a balance of charge and discharge of the lead battery. An in-vehicle power distribution device with a battery state detection function according to claim 1,
When the control means starts to charge or discharge the lead battery, the charge / discharge current value detected via the current detection means and the charge / discharge detected via the voltage detection means The state of the lead battery is detected based on the amount of change in the terminal voltage before and after the start of the battery, and the opening / closing means is selectively turned on / off so that the state of the lead battery is stabilized based on the detection result An on-vehicle power distribution device with a battery state detection function characterized by controlling. An in-vehicle power distribution device with a battery state detection function according to claim 2,
The control means derives an internal resistance value of the lead battery based on the charge / discharge current value and the change amount of the terminal voltage, and detects the state of the lead battery based on the internal resistance value. A vehicle-mounted power distribution device with a battery state detection function. An in-vehicle power distribution device with a battery state detection function according to claim 3,
The control means includes a charge internal resistance value that is the internal resistance value derived when the lead battery is charged, and a discharge that is the internal resistance value that is derived when the lead battery is discharged. A vehicle-mounted power distribution device with a battery state detection function, wherein the state of the lead battery is detected based on an internal resistance value. An in-vehicle power distribution device with a battery state detection function according to claim 4,
The on-board power distribution device with a battery state detection function, wherein the control means detects the state of the lead battery based on a ratio between the charge internal resistance value and the discharge internal resistance value. The vehicle-mounted power distribution device with a battery state detection function according to any one of claims 2 to 5,
The control unit detects at least one of a remaining battery level and a degree of deterioration of the lead battery based on the charge / discharge current value and the amount of change in the terminal voltage. In-vehicle power distribution device with detection function. An in-vehicle power distribution device with a battery state detection function according to claim 1,
When the control unit starts charging the lead battery, the control unit detects an increase in the terminal voltage of the lead battery per predetermined time accompanying the start of charging via the voltage detecting unit, The state of the lead battery is detected based on the amount of increase of the battery, and the open / close means is selectively on / off controlled so that the state of the lead battery is stabilized based on the detection result. In-vehicle power distribution device with functions. An in-vehicle power distribution device with a battery state detection function according to claim 7,
The vehicle-mounted power distribution device with a battery state detection function, wherein the control means detects at least one of a remaining battery level and a deterioration level of the lead battery based on the amount of increase per predetermined time. .

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