JP2014019328A - Control device for hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device for a hybrid vehicle that can reduce abnormal noise and vibration in switching of a travelling mode.SOLUTION: The control device, which is applied to a hybrid vehicle 1 which can switch a travelling mode to an EV mode, a parallel mode and a series parallel mode, if predetermined start-up conditions for starting an internal-combustion engine 10 are met when the travelling mode is switched to the EV mode, actuates the internal combustion engine 10 by cranking the internal combustion engine 10 with a first motor generator 11 while releasing a clutch mechanism 25 so that a first sun gear S1 of a first planetary gear train 11 is disconnected from an output shaft 18 and while locking a lock mechanism 24 so that a second sun gear S2 of a second planetary gear train 22 may not rotate. The conditions for actuating include switching of the travelling mode of the vehicle 1 from the EV mode to the parallel mode or the series parallel mode.

Description

  In the present invention, an internal combustion engine and an electric motor are mounted as a driving source for traveling, and the traveling mode is an EV mode in which the internal combustion engine is separated from the drive wheels and travels by the motor, a parallel mode in which the traveling is mainly performed by the internal combustion engine, and an internal combustion engine The present invention relates to a control device applied to a hybrid vehicle capable of switching to a series parallel mode in which power is divided into drive wheels and a generator.

  A hybrid vehicle in which an internal combustion engine and an electric motor are mounted as a driving source for traveling is known. As hybrid vehicle drive systems, for example, a series hybrid, a parallel hybrid, a series parallel hybrid, and the like are known. And the hybrid vehicle comprised so that these drive systems can be switched according to a vehicle speed and a torque is known (refer patent document 1).

JP 2000-209706 A

  In the hybrid vehicle shown in FIG. 18 of Patent Document 1, a first clutch is provided between the ring gear of the planetary gear mechanism and the motor. A second clutch is provided between the ring gear of the planetary gear mechanism and the carrier. In this hybrid vehicle, the drive system is switched by switching the states of these two clutches. Thus, the vehicle travel mode is switched. As a clutch provided in a vehicle drive device, a clutch that requires synchronous control when engaged, for example, a dog clutch, is known. In this hybrid vehicle of Patent Document 1, when such a clutch requiring synchronization control is provided as the first clutch and the second clutch, the synchronization control is performed by a motor connected to the sun gear of the planetary gear mechanism. In this case, the rotational speed control of the ring gear or the carrier is performed via a planetary gear mechanism. Therefore, the synchronous control is affected by the backlash of each part of the planetary gear mechanism. Therefore, abnormal noise and vibration may occur when the driving mode is switched.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a hybrid vehicle control device that can suppress abnormal noise and vibration during switching of travel modes.

  The control device of the present invention includes an internal combustion engine, a motor / generator functioning as an electric motor and a generator, an output member connected to drive wheels so as to be able to transmit power, an electric motor capable of outputting power to the output member, A battery electrically connected to the electric motor and the motor / generator; a single pinion type first planetary gear mechanism; and a single pinion type second planetary gear mechanism, wherein the carrier of the first planetary gear mechanism and the second A first rotating element configured by connecting a ring gear of the planetary gear mechanism is connected to an output shaft of the internal combustion engine, and connecting a ring gear of the first planetary gear mechanism and a carrier of the second planetary gear mechanism. A differential mechanism in which the configured second rotating element is connected to a rotor shaft of the motor / generator, a sun gear of the first planetary gear mechanism, and the output member are used as power. A clutch mechanism that can be switched between an engaged state that is reachably connected and a released state in which the sun gear of the first planetary gear mechanism and the output member are separated; and the sun gear of the second planetary gear mechanism cannot rotate. An EV mode in which the clutch mechanism is switched to the disengaged state and the drive wheels are driven by the electric motor. The lock mechanism is switched to the locked state and the clutch mechanism is switched to the engaged state to drive the drive wheels in at least one of the internal combustion engine and the electric motor, and the lock mechanism is unlocked And switching the clutch mechanism to the engaged state, the internal combustion engine and the electric motor Applied to a hybrid vehicle capable of switching the driving mode to at least one of the series parallel mode for driving the driving wheel, and to the charging state of the battery, the driving force required for the vehicle, and the speed of the vehicle And the control means for controlling the clutch mechanism, the lock mechanism, the internal combustion engine and the electric motor so that the travel mode of the vehicle is switched based on, and the internal combustion engine is started when the travel mode of the vehicle is the EV mode. When a predetermined starting condition to be satisfied is satisfied, the internal combustion engine is cranked by the motor / generator with the clutch mechanism in the released state and the lock mechanism is in the locked state, and the internal combustion engine is started. Starting means for performing the EV mode. A case where the mode is switched to the parallel mode or the series parallel mode is included.

  According to the control device of the present invention, when the starting condition is satisfied when the travel mode is the EV mode, the clutch mechanism is released, so that the sun gear and the output member of the first planetary gear mechanism can be disconnected. . Since the internal combustion engine is cranked in this state, it is possible to suppress abnormal noise and vibration of the vehicle when the internal combustion engine is started. The start condition includes a case where the travel mode is switched from the EV mode to another travel mode. Therefore, by suppressing the vibration of the vehicle in this way, it is possible to suppress abnormal noise and vibration during switching of the travel mode.

  In one aspect of the control device of the present invention, the control means is configured such that the running state of the vehicle specified by the speed of the vehicle and the driving force required for the vehicle is within a predetermined EV mode region. The vehicle driving mode is switched to the EV mode, and the vehicle driving mode is switched to the parallel mode when the vehicle driving state is within a predetermined parallel mode region. The parallel mode region has a predetermined determination. An operation region that is greater than or equal to the speed and less than or equal to a predetermined determination drive force may be included, and the EV mode region may include an operation region that is less than the determination speed and less than or equal to the determination drive force. . According to this aspect, the vehicle is switched to the EV mode when the vehicle travels at a low torque and a low vehicle speed. In this case, since it is possible to suppress the internal combustion engine from being operated at a low speed, fuel consumption can be improved. The parallel mode region includes an operation region that is equal to or higher than the determination speed and equal to or lower than the determination driving force. Therefore, even if the vehicle is operated for a long time with a determination driving force or less, it is possible to suppress the motor from being continuously operated for a long time.

  In this embodiment, the control means includes area changing means for changing the size of the EV mode area according to the state of charge of the battery so that the EV mode area becomes smaller as the remaining amount of the battery is smaller. (Claim 3). Thus, by changing the size of the EV mode area, it is possible to secure the remaining battery level.

  As described above, according to the control device of the present invention, when the starting condition is satisfied when the traveling mode is the EV mode, the clutch mechanism is released, so that the sun gear and the output of the first planetary gear mechanism are output. The member can be separated. Therefore, it is possible to suppress abnormal noise and vibration of the vehicle when the internal combustion engine is started. In addition, since the start condition includes a case where the travel mode is switched from the EV mode to another travel mode, it is possible to suppress abnormal noise and vibration when the travel mode is switched.

The figure which shows roughly the hybrid vehicle incorporating the control apparatus which concerns on one form of this invention. The alignment chart in EV mode. The alignment chart in parallel mode. Collinear diagram in series parallel mode. The figure which shows the relationship between vehicle speed, the driving force requested | required of the vehicle, and driving modes.

  FIG. 1 schematically shows a hybrid vehicle in which a control device according to one embodiment of the present invention is incorporated. The vehicle 1 includes an internal combustion engine (hereinafter sometimes referred to as an engine) 10, a first motor / generator (hereinafter sometimes abbreviated as a first MG) 11, and a second motor / generator (hereinafter referred to as a first motor / generator). (It may be abbreviated as second MG.) The engine 10 is a known spark ignition type internal combustion engine mounted on a hybrid vehicle. Therefore, detailed description is omitted.

  The first MG 11 and the second MG 12 are well-known motor generators that function as an electric motor and a generator. The first MG 11 includes a rotor 11b that rotates integrally with the rotor shaft 11a, and a stator 11c that is coaxially disposed on the outer periphery of the rotor 11b and fixed to a case (not shown). Similarly, the second MG 12 includes a rotor 12b that rotates integrally with the rotor shaft 12a, and a stator 12c that is coaxially disposed on the outer periphery of the rotor 12b and fixed to the case. First MG 11 is electrically connected to battery 14 via first inverter 13. The second MG 12 is electrically connected to the battery 14 via the second inverter 15.

  The vehicle 1 is provided with a power split mechanism 16 and an output unit 17 for transmitting power to the drive wheels 2 of the vehicle 1. The output unit 17 includes an output shaft 18 as an output member and an output gear 19 that rotates integrally with the output shaft 18. The output gear 19 meshes with a ring gear 20 a provided in the case of the differential mechanism 20. The differential mechanism 20 is a known mechanism that distributes the transmitted power to the left and right drive wheels 2.

  The power split mechanism 16 includes a first planetary gear mechanism 21 and a second planetary gear mechanism 22. The first planetary gear mechanism 21 and the second planetary gear mechanism 22 are both single-pinion type planetary gear mechanisms. The first planetary gear mechanism 21 includes a first sun gear S1, a first ring gear R1, a first pinion gear P1, and a first carrier C1. The first sun gear S1 is an external gear. The first ring gear R1 is an internal gear. The first ring gear R1 is disposed coaxially with the first sun gear S1. The first pinion gear P1 meshes with each of the first sun gear S1 and the first ring gear R1. The first carrier C1 supports the first pinion gear P1 such that it can rotate and can revolve around the first sun gear S1. The second planetary gear mechanism 22 includes a second sun gear S2, a second ring gear R2, a second pinion gear P2, and a second carrier C2. The second sun gear S2 is an external gear. The second ring gear R2 is an internal gear. The second ring gear R2 is disposed coaxially with the second sun gear S2. Second pinion gear P2 meshes with each of second sun gear S2 and second ring gear R2. The second carrier C2 supports the second pinion gear P2 such that it can rotate and can revolve around the second sun gear S2.

  As shown in this figure, the output shaft 10a of the engine 10, the first carrier C1, and the second ring gear R2 are connected to rotate integrally. Therefore, these correspond to the first rotating element of the present invention. Further, the rotor shaft 11a of the first MG 11, the second carrier C2, and the first ring gear R1 are connected so as to rotate integrally. Therefore, these correspond to the second rotating element of the present invention. As shown in this figure, the output shaft 10a of the engine 10 supports the first drive gear 23 so as to be rotatable relative to the output shaft 10a. The first sun gear S1 is connected to the first drive gear 23 so as to rotate integrally. By being connected in this way, the first planetary gear mechanism 71 and the second planetary gear mechanism 72 correspond to the differential mechanism of the present invention.

  As shown in this figure, the power split mechanism 16 is provided with a lock mechanism 24 and a clutch mechanism 25. The lock mechanism 24 is configured to be switchable between a locked state in which the second sun gear S2 is locked so as not to rotate and an unlocked state in which the lock is released. The clutch mechanism 25 is configured as a dog clutch. The clutch mechanism 25 includes a first clutch member 26, a second clutch member 27, and a sleeve 28. The first clutch member 26 is fixed to the output shaft 18. The power split mechanism 16 includes an intermediate gear 29 that meshes with the first drive gear 23. As shown in this figure, the output shaft 18 supports the second clutch member 27 and the intermediate gear 29 so as to be rotatable relative to the output shaft 18. The second clutch member 27 is coupled to rotate integrally with the intermediate gear 29. The sleeve 28 can move to an engagement position for connecting the first clutch member 26 and the second clutch member 27 and a release position for releasing the connection. In this figure, the sleeve 28 in the engagement position is shown above the output shaft 18, and the sleeve 28 in the release position is shown below the output shaft 18. Hereinafter, the case where the sleeve 28 is in the engagement position is referred to as an engagement state, and the case where the sleeve 28 is in the release position is referred to as a release state.

  As shown in this figure, the output shaft 18 is provided with a driven gear 30 that rotates integrally with the output shaft 18. A second drive gear 31 is provided on the rotor shaft 12 a of the second MG 12. The second drive gear 31 meshes with the driven gear 30. Therefore, the second MG 12 corresponds to the electric motor of the present invention.

  The engine 10, the first MG 11, the second MG 12, the lock mechanism 24, and the clutch mechanism 25 are controlled by the vehicle control device 40. The vehicle control device 40 is configured as a computer unit including a microprocessor and peripheral devices such as RAM and ROM necessary for its operation. The vehicle control device 40 holds various control programs for causing the vehicle 1 to travel appropriately. The vehicle control device 40 executes control of the control target such as the engine 10 and the MGs 11 and 12 by executing these programs. The vehicle control device 40 controls the first MG 11 by controlling the first inverter 13. Further, the vehicle control device 40 controls the second MG 12 by controlling the second inverter 15. Various sensors for acquiring information relating to the vehicle 1 are connected to the vehicle control device 40. For example, an accelerator opening sensor 41, a vehicle speed sensor 42, a battery sensor 43, and the like are connected to the vehicle control device 40. The accelerator opening sensor 41 outputs a signal corresponding to the depression amount of the accelerator pedal, that is, the accelerator opening. The vehicle speed sensor 42 outputs a signal corresponding to the speed (vehicle speed) of the vehicle 1. The battery sensor 43 outputs a signal corresponding to the state of charge of the battery 14. In addition to this, various sensors are connected to the vehicle control device 40, but their illustration is omitted.

  In the vehicle 1, a plurality of travel modes are realized by appropriately controlling the engine 10, the first MG 11, the second MG 12, the lock mechanism 24, and the clutch mechanism 25. The EV mode, the parallel mode, and the series parallel mode are set as the plurality of travel modes. Each travel mode will be described with reference to FIGS. FIG. 2 shows an alignment chart in the EV mode. FIG. 3 shows an alignment chart in the parallel mode. FIG. 4 shows an alignment chart in the series parallel mode. In these drawings, “ENG” indicates the engine 10 and “OUT” indicates the output shaft 18. “MG1” indicates the first MG11, and “MG2” indicates the second MG12. “S1” indicates the first sun gear S1, “R1” indicates the first ring gear R1, and “C1” indicates the first carrier C1. “S2” indicates the second sun gear S2, “R2” indicates the second ring gear R2, and “C2” indicates the second carrier C2.

  In the EV mode, the lock mechanism 24 is switched to the locked state, and the clutch mechanism 25 is switched to the released state. When the clutch mechanism 25 is switched to the released state, the output unit 17 and the power split mechanism 16 are disconnected. Therefore, the drive wheel 2 is driven by the second MG 12. Since the lock mechanism 24 is switched to the locked state, the first MG 11 and the engine 10 are connected so that power can be transmitted. Therefore, the engine 10 can be cranked by the first MG 11. Further, the engine 10 can drive the first MG 11 to generate power. FIG. 2 is a collinear diagram when the engine 10 and the first MG 11 are stopped. Thus, in the EV mode, the driving method of the vehicle 1 is a series hybrid.

  In the parallel mode, the lock mechanism 24 is switched to the locked state, and the clutch mechanism 25 is switched to the engaged state. When the clutch mechanism 25 is switched to the engaged state in this way, the first sun gear S1 and the output shaft 18 are connected so as to transmit power as shown in FIG. Since the lock mechanism 24 is switched to the locked state, the second sun gear S2 is locked so as not to rotate. In this case, the gear ratio of each rotating element of the first planetary gear mechanism 21 and the second planetary gear mechanism 22 is fixed. Further, as shown in this figure, a reaction force against the output of the engine 10 can be generated by the lock mechanism 24. Therefore, the output of the engine 10 can be transmitted to the output shaft 18 without operating the first MG 11. Therefore, in the parallel mode, the drive wheel 2 can be driven by the engine 10 and the second MG 12. Thus, in the parallel mode, the driving method of the vehicle 1 is a parallel hybrid.

  In the series parallel mode, the lock mechanism 24 is switched to the unlocked state, and the clutch mechanism 25 is switched to the released state. In this case, since the lock mechanism 24 is switched to the unlocked state, the second sun gear S2 can rotate. And since the clutch mechanism 25 is switched to an engagement state, the 1st sun gear S1 and the output shaft 18 are connected so that power transmission is possible. In this case, the output of the engine 10 can be divided into the first MG 11 and the output shaft 18 as shown in FIG. Therefore, the drive wheel 2 can be driven by the engine 10 and the second MG 12 even in the series parallel mode. Further, the engine 10 can generate power by driving the first MG 11. Thus, in the series / parallel mode, the drive system of the vehicle 1 is a series / parallel hybrid.

  The vehicle control device 40 switches between these travel modes based on the map shown in FIG. This figure shows the relationship between the vehicle speed, the driving force required for the vehicle 1, and the travel mode. The series parallel mode region Rsp in this figure is a region where the traveling mode is switched to the series parallel mode. The parallel mode region Rp is a region where the traveling mode is switched to the parallel mode. The EV mode area Rev is an area where the traveling mode is switched to the EV mode. The relationship shown in this figure may be obtained in advance by experiment or numerical calculation and stored in the vehicle control device 40 as a map.

  As shown in this figure, in the parallel mode region Rp, an operation region between a predetermined first vehicle speed V1 and a predetermined second vehicle speed V2 and equal to or less than a predetermined determination driving force P is set. The EV mode area Rev is set so as to include an operation area that is less than the first vehicle speed V1 and equal to or less than the determination driving force P. Therefore, the first vehicle speed V1 corresponds to the determination speed of the present invention. As shown in this figure, the size of the EV mode area Rev is changed according to the state of charge of the battery 14 so as to decrease as the remaining amount of the battery 14 decreases. When the state of charge of the battery 14 is high, in other words, when the remaining amount of the battery 14 is large, the range surrounded by the line Lh is set as the EV mode region Rev. On the other hand, when the state of charge of the battery 14 is low, in other words, when the remaining amount of the battery 14 is low, the range surrounded by the line Ll is set as the EV mode region Rev. Thus, by changing the EV mode area, the vehicle control device 40 functions as the area changing means of the present invention.

  The vehicle control device 40 first acquires the traveling state of the vehicle 1 based on the vehicle speed and the driving force required for the vehicle 1. Thereafter, the travel mode is switched according to which region the acquired travel state is in. As shown in this figure, the EV mode region Rev when the state of charge of the battery 14 is high overlaps the parallel mode region Rp. When the traveling state of the vehicle 1 is in a portion where the region Rev and the region Rp overlap, the traveling mode is switched according to a predetermined rule set in advance. For example, when the region Rev and the region Rp overlap, the rule is set so that the EV mode is selected. Thus, the vehicle control device 40 functions as the control means of the present invention by switching the travel modes.

  Further, vehicle control device 40 cranks engine 10 with first MG 11 when a predetermined start condition for starting engine 10 is satisfied when the travel mode is the EV mode. Note that it is determined that the start condition is satisfied when, for example, the travel mode is switched from the EV mode to another travel mode, or when the first MG 11 needs to generate power. At this time, the vehicle control device 40 cranks the engine 10 by the first MG 11 with the clutch mechanism 25 in the released state and the lock mechanism 24 in the locked state. As a result, the engine 10 is started. By starting the engine 10 in this way, the vehicle control device 40 functions as the starting means of the present invention.

  As described above, according to the present invention, when the starting condition is satisfied when the traveling mode is the EV mode, the engine 10 is cranked by the first MG 11 with the clutch mechanism 25 in the released state. In this case, the output unit 17 is disconnected from the power split mechanism 16. Therefore, it is possible to prevent vibration generated in the engine 10, the first MG 11 or the power split mechanism 16 from being transmitted to the output unit 17 when the engine 10 is started. Therefore, abnormal noise and vibration of the vehicle 1 when the engine 10 is started can be suppressed. As described above, the start condition is satisfied when the travel mode is switched to another travel mode. Therefore, by suppressing the abnormal noise and vibration of the vehicle 1 in this way, it is possible to suppress the abnormal noise and vibration when the traveling mode is switched. Further, according to the present invention, as shown in FIGS. 3 and 4, a state where the rotational speed of the first sun gear S <b> 1 is higher than the rotational speed of the engine 10, a so-called overdrive state can be achieved. Thereby, since the rotation speed of the engine 10 can be lowered | hung, a fuel consumption can be improved.

  Since the EV mode region Rev includes a driving region that is less than the first vehicle speed V1 and equal to or less than the determination driving force P, the EV mode region Rev is switched to the EV mode when the vehicle 1A travels at low torque and low vehicle speed. Thereby, since it can suppress that the engine 10 is drive | operated at low speed, a fuel consumption can be improved. In addition, since the parallel mode region Rp includes an operation region in which the first vehicle speed V1 is greater than or equal to and less than or equal to the determination drive force P, the second MG 12 continues for a long time even if the vehicle 1A is operated for a long time with the determination drive force P or less. Driving can be suppressed. And since the magnitude | size of EV mode area | region Rev is changed according to the residual amount of the battery 14, the residual amount of the battery 14 is securable.

  This invention is not limited to each form mentioned above, It can implement with a various form. For example, the internal combustion engine of the hybrid vehicle to which the present invention is applied may be a diesel engine. An electric motor may be provided instead of the second MG.

DESCRIPTION OF SYMBOLS 1 Hybrid vehicle 2 Drive wheel 10 Internal combustion engine 10a Output shaft 11 1st motor generator 11a Rotor shaft 12 2nd motor generator (electric motor)
14 Battery 18 Output shaft (output member)
21 First planetary gear mechanism (differential mechanism)
22 Second planetary gear mechanism (differential mechanism)
24 lock mechanism 25 clutch mechanism 40 vehicle control device (control means, starting means, region changing means)
S1 Sun gear of the first planetary gear mechanism (first sun gear)
R1 Ring gear (first ring gear) of the first planetary gear mechanism
C1 First planetary gear mechanism carrier (first carrier)
S2 Sun gear of the second planetary gear mechanism (second sun gear)
R2 Ring gear of the second planetary gear mechanism (second ring gear)
C2 Second planetary gear mechanism carrier (second carrier)

Claims (3)

An internal combustion engine;
A motor / generator functioning as an electric motor and a generator;
An output member connected to the drive wheel to transmit power;
An electric motor capable of outputting power to the output member;
A battery electrically connected to the electric motor and the motor generator;
A first rotation comprising a single pinion type first planetary gear mechanism and a single pinion type second planetary gear mechanism, wherein the carrier of the first planetary gear mechanism and the ring gear of the second planetary gear mechanism are connected. A second rotating element having an element connected to the output shaft of the internal combustion engine and connecting a ring gear of the first planetary gear mechanism and a carrier of the second planetary gear mechanism to a rotor shaft of the motor / generator; A connected differential mechanism;
Switchable between an engagement state in which the sun gear of the first planetary gear mechanism and the output member are connected so as to be able to transmit power, and a released state in which the sun gear of the first planetary gear mechanism and the output member are disconnected. A clutch mechanism;
A lock mechanism that can be switched between a locked state in which the sun gear of the second planetary gear mechanism is non-rotatably locked and an unlocked state in which the lock is released;
With
The clutch mechanism is switched to the disengaged state, the EV mode is configured to drive the drive wheels by the electric motor, the lock mechanism is switched to the locked state, and the clutch mechanism is switched to the engaged state, and the internal combustion engine and the electric motor At least one of the parallel mode for driving the drive wheel, the lock mechanism is switched to the unlocked state, the clutch mechanism is switched to the engaged state, and at least one of the internal combustion engine and the electric motor Applied to a hybrid vehicle capable of switching the driving mode to the series parallel mode for driving the driving wheel,
The clutch mechanism, the lock mechanism, the internal combustion engine, and the electric motor are controlled so that the traveling mode of the vehicle is switched based on the state of charge of the battery, the driving force required for the vehicle, and the speed of the vehicle. Control means;
When a predetermined start condition for starting the internal combustion engine is satisfied when the vehicle travel mode is the EV mode, the clutch mechanism is in the released state and the lock mechanism is in the locked state. Starting means for cranking the internal combustion engine by a motor generator to start the internal combustion engine,
The start condition includes a control device including a case where the traveling mode of the vehicle is switched from the EV mode to the parallel mode or the series parallel mode. The control means changes the vehicle travel mode to the EV mode when the vehicle travel state specified by the speed of the vehicle and the driving force required for the vehicle is within a predetermined EV mode region. Switching, when the traveling state of the vehicle is within a predetermined parallel mode region, switching the traveling mode of the vehicle to the parallel mode,
The parallel mode region includes an operation region that is equal to or higher than a predetermined determination speed and equal to or lower than a predetermined determination driving force.
The control device according to claim 1, wherein the EV mode region includes an operation region that is less than the determination speed and equal to or less than the determination driving force.   The control unit includes a region changing unit that changes a size of the EV mode region according to a state of charge of the battery so that the EV mode region becomes smaller as the remaining amount of the battery is smaller. The control device described in 1.

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