JP7050485B2 - Hybrid vehicle drive - Google Patents

Description

The present invention relates to a drive device for a hybrid vehicle including an engine and a motor generator (electric motor) as a drive force source.

In recent years, hybrid electric vehicles (HEVs) and plug-in hybrid electric vehicles (PHVs) that can effectively improve the fuel consumption rate (fuel efficiency) of vehicles by using an engine and an electric motor together have been widely put into practical use. .. In addition, an electric vehicle (EV) that uses only an electric motor as a power source and does not emit exhaust gas has also been put into practical use.

Here, Patent Document 1 discloses a hybrid vehicle having a hybrid traveling mode, a motor traveling mode, and a regenerative traveling mode as traveling modes. More specifically, in the hybrid driving mode, the hybrid vehicle travels by using both the engine and the motor generator MG2 as a driving force source while causing the motor generator MG1 to generate electric power by utilizing the engine output of the engine. In the motor running mode, the motor generator MG2 is used as a driving force source for running with the engine stopped. In the regenerative traveling mode, the motor generator MG2 generates electricity by using the energy input via the reduction gear when a predetermined condition such as a deceleration request is satisfied.

Here, the reduction gear has a sun gear connected to the motor generator MG2, a ring gear arranged concentrically with the sun gear, a plurality of pinion gears that mesh with the sun gear and the ring gear, and one end thereof is fixed to the main body case and the other end. Is equipped with a carrier having a support shaft that supports the pinion gear on its axis. That is, the reduction gear constitutes a planetary gear mechanism that amplifies the drive torque by decelerating the rotation transmitted from the motor generator MG2 using the sun gear, the ring gear, and the pinion gear as rotation elements.

When the motor generator MG2 functions as a motor, the reduction gear decelerates the rotation transmitted from the motor generator MG2 to amplify the drive torque and output it from the ring gear. On the other hand, the reduction gear accelerates the rotation by the power input to the ring gear to attenuate the drive torque and outputs it from the sun gear, thereby causing the motor generator MG2 to function as a generator.

Japanese Unexamined Patent Publication No. 2014-125048

As described above, in the hybrid vehicle of Patent Document 1, torque is transmitted (input / output) via the reduction gear both during driving (hybrid traveling mode, motor traveling mode) and during regeneration (regenerative traveling mode). Here, the rotation speed of the motor generator MG2 at the time of regeneration depends on the gear ratio of the reduction gear.

However, the gear ratio of the reduction gear (motor / reduction gear) is set in consideration of the motor assist torque (drive torque) required at the time of driving, that is, the gear ratio of the reduction gear is set according to the drive side. Therefore, the gear ratio is not always suitable for regeneration. Therefore, the amount of regeneration (regeneration efficiency) may decrease. Further, for example, when the charge amount / charge state (SOC) of the battery is sufficient (that is, when the battery cannot be charged), regeneration cannot be performed. Therefore, the improvement of fuel efficiency of the vehicle may be suppressed (hindered).

The present invention has been made to solve the above-mentioned problems, and it is possible to increase the amount of regeneration at the time of regeneration without lowering the driving torque at the time of driving, and to further improve the fuel consumption rate (fuel consumption). It is intended to provide a possible hybrid vehicle drive.

The drive device for a hybrid vehicle according to the present invention is a drive device for a hybrid vehicle including an engine and a motor generator, in which the front wheel axle, the engine and the motor, which transmit torque between the engine and the motor generator and the front wheels, are used. It has a rear wheel axle that transmits torque between the generator and the rear wheels, a center differential unit that absorbs the rotation difference between the front wheel axle and the rear wheel axle, and multiple gear pairs that are interposed in the front wheel axle. The first gear stage switching mechanism that converts the input torque and outputs it, and the second gear stage that is interposed in the rear wheel axle and has multiple gear pairs and converts the input torque and outputs it. Of the plurality of gear pairs constituting the switching mechanism and the first gear stage switching mechanism, the first switching means for switching the gear pair connected to the front wheel axle and the plurality of gear pairs constituting the second gear stage switching mechanism. Among them, a second switching means for switching a gear pair connected to the rear wheel axle and a control means for controlling the drive of the first switching means and the second switching means based on the operating state of the vehicle are provided. do.

According to the drive device of the hybrid vehicle according to the present invention, the first gear stage switching mechanism, which is interposed in the front wheel axle, has a plurality of gear pairs, converts the input torque and outputs it, and the rear wheel axle. A plurality of intervening gear pairs, having a plurality of gear pairs, having a second gear stage switching mechanism that converts and outputs the input torque, and constituting the first gear stage switching mechanism based on the operating state of the vehicle. Of the gear pairs of the above, the gear pair connected to the front wheel axle is switched, and among the plurality of gear pairs constituting the second gear stage switching mechanism, the gear pair connected to the rear wheel axle is switched. Therefore, for example, the gear ratios of the first gear stage switching mechanism and the second gear stage switching mechanism can be switched between driving and regeneration. That is, at the time of driving (acceleration), a gear pair with a gear ratio suitable for driving (acceleration) can be used, and at the time of regeneration, a gear pair with a gear ratio suitable for regeneration (good regeneration efficiency) can be used. As a result, the amount of regeneration during regeneration can be increased without reducing the driving torque during driving, and fuel efficiency can be further improved.

In the drive device of the hybrid vehicle according to the present invention, the gear ratio of each gear pair included in the first gear stage switching mechanism and the gear ratio of each gear pair included in the second gear stage switching mechanism are set to be the same. Is preferable.

By doing so, it is possible to prevent an unnecessary rotation difference from occurring between the front wheels and the rear wheels.

In the drive device of the hybrid vehicle according to the present invention, when the accelerator operation is turned off, the control means has a higher gear than the plurality of gear pairs constituting the first gear stage switching mechanism when viewed from the front wheel side. It is preferable to switch to a higher gear pair and to switch to a higher gear pair when viewed from the rear wheel side among the plurality of gear pairs constituting the second gear stage switching mechanism.

In this case, when the accelerator operation is off, the gear pair is switched to a higher gear pair when viewed from the front wheel side among the plurality of gear pairs constituting the first gear stage switching mechanism, and the second gear stage switching is performed. Of the plurality of gear pairs constituting the mechanism, the gear pair can be switched to a higher gear pair when viewed from the rear wheel side. Therefore, for example, when the vehicle is in the coasting state, the rotation speed of the motor generator can be increased, that is, the regeneration efficiency can be increased to execute the regeneration operation.

In the drive device of the hybrid vehicle according to the present invention, the first switching means is provided on the outer periphery of the first hub that rotates integrally with the front wheel axle and the first hub that is slidably slidable in the axial direction. It has a sleeve and a first actuator that switches a gear pair connected to a front wheel axle among a plurality of gear pairs by sliding a first sleeve and switching a gear pair connected to the first hub. The second switching means slides the second hub that rotates integrally with the rear wheel axle, the second sleeve that is slidably provided in the axial direction on the outer periphery of the second hub, and the second sleeve. , It is preferable to have a second actuator that switches the gear pair connected to the rear wheel axle among the plurality of gear pairs by switching the gear pair connected to the second hub.

In this case, by moving the first sleeve and switching the gear pair connected to the first hub, the gear pair connected to the front wheel axle can be switched among the plurality of gear pairs constituting the first gear stage switching mechanism. .. Therefore, the gear ratio (final gear ratio) on the front wheel side can be switched by sliding the first sleeve with the first actuator. Similarly, by moving the second sleeve and switching the gear pair connected to the second hub, the gear pair connected to the rear wheel axle is switched among the plurality of gear pairs constituting the second gear stage switching mechanism. Be done. Therefore, the gear ratio (final gear ratio) on the rear wheel side can be switched by sliding the second sleeve with the second actuator.

In the drive device of the hybrid vehicle according to the present invention, the first switching means is configured to be able to take a neutral state in which the front wheel axle is not connected to any gear pair, and the second switching means is rearward. It is preferable that the wheel axle is configured to be in a neutral state in which it is not connected to any gear pair.

By doing so, the first switching means is set to the neutral state in which the front wheel axle is not connected to any gear pair, thereby blocking the torque transmission with the front wheels (disconnecting the front wheels) and reducing the drag loss. Can be reduced. Further, by setting the second switching means in a neutral state in which the rear wheel axle is not connected to any gear pair, torque transmission with the rear wheels is cut off (rear wheels are separated), and drag loss is reduced. can do. Further, for example, when the charge / charge state (SOC) of the battery is sufficient (that is, the battery cannot be charged) and regeneration cannot be performed, all the front wheels and the rear wheels should be separated to reduce the drag loss. You can also. That is, the vehicle is driven in an AWD (all-wheel drive) state, an FF (front wheel drive) state in which the rear wheels are separated, an FR (rear wheel drive) state in which the front wheels are separated, and N in which all wheels are separated. You can switch between (neutral: neutral) states. Therefore, depending on the driving condition of the vehicle (for example, required driving force (accelerator opening), vehicle speed, SOC, etc.), the drive type and front wheel axle are set so that the efficiency of the vehicle (driving device) is the best as a whole. It is possible to switch the gear ratio and the gear ratio of the rear wheel axle.

In the drive device of the hybrid vehicle according to the present invention, there is a synchro mechanism that synchronizes the rotation of both gears between the first hub and one of the gears constituting each gear pair included in the first gear stage switching mechanism. It is preferable that a synchro mechanism for synchronizing the rotations of both gears is provided between the second hub and one of the gears constituting each gear pair included in the second gear stage switching mechanism. ..

In this case, since one of the gears constituting each gear pair included in the first gear stage switching mechanism and the first hub (sleeve) are provided with a synchro mechanism for synchronizing the rotation of both gears. When mating the sleeve with the spline provided on the gear, the sleeve and the spline provided on the gear are connected more smoothly even if the rotation speeds of the first hub (sleeve) and the gear are different. can do. Similarly, since one of the gears constituting each gear pair included in the second gear stage switching mechanism and the second hub (sleeve) are provided with a synchro mechanism for synchronizing the rotation of both gears. When mating the sleeve with the spline provided on the gear, the sleeve and the spline provided on the gear are connected more smoothly even if the rotation speeds of the second hub (sleeve) and the gear are different. can do.

In the drive device of the hybrid vehicle according to the present invention, when the control means moves the first sleeve and switches the gear pair connected to the front wheel axle, the first switching means is temporarily set to the neutral state and connected. When controlling the rotation speed of the motor generator so that the rotation speed of the gear pair matches the rotation speed of the front wheel axle, moving the second sleeve, and switching the gear pair connected to the rear wheel axle, the second gear pair It is preferable to temporarily set the switching means to the neutral state and control the rotation speed of the motor / generator so that the rotation speed of the connected gear pair is matched with the rotation speed of the rear wheel axle.

In this case, when the first sleeve is moved to switch the gear pair connected to the front wheel axle, the first switching means is temporarily set to the neutral state, and the rotation speed of the connected gear pair is set to the rotation speed of the front wheel axle. The number of revolutions of the motor generator is controlled so as to match the number. Therefore, it is possible to reduce the shock (switching shock) when switching the gear pair. Similarly, when the second sleeve is moved to switch the gear pair connected to the rear wheel axle, the second switching means is temporarily set to the neutral state, and the rotation speed of the connected gear pair is set to the rear wheel axle. The rotation speed of the motor / generator is controlled so as to match the rotation speed of. Therefore, it is possible to reduce the shock (switching shock) when switching the gear pair.

According to the present invention, in a drive device of a hybrid vehicle including an engine and a motor / generator, the amount of regeneration during regeneration can be increased without reducing the drive torque during drive, and the fuel consumption rate (fuel consumption) can be further improved. It will be possible to improve.

It is a skeleton diagram which shows the structure of the drive device of the hybrid vehicle which concerns on embodiment, and is a block diagram which shows the structure of the control system. It is a list which shows the driving mode which can take in the drive device of the hybrid vehicle which concerns on embodiment. It is a figure which shows the torque transmission path (thick line) via the 1st gear stage switching mechanism and the 2nd gear stage switching mechanism in traveling mode 1. FIG. It is a figure which shows the torque transmission path (thick line) via the 1st gear stage switching mechanism and the 2nd gear stage switching mechanism in traveling mode 2. It is a figure which shows the torque transmission path (thick line) via the 1st gear stage switching mechanism and the 2nd gear stage switching mechanism in traveling mode 3. It is a figure which shows the torque transmission path (thick line) via the 1st gear stage switching mechanism and the 2nd gear stage switching mechanism in traveling mode 4. It is a figure which shows the torque transmission path (thick line) via the 1st gear stage switching mechanism and the 2nd gear stage switching mechanism in traveling mode 6. It is a figure which shows the torque transmission path (thick line) via the 1st gear stage switching mechanism and the 2nd gear stage switching mechanism in traveling mode 7. It is a figure which shows the torque transmission path (thick line) via the 1st gear stage switching mechanism and the 2nd gear stage switching mechanism in traveling mode 8. It is a figure which shows the torque transmission path (thick line) via the 1st gear stage switching mechanism and the 2nd gear stage switching mechanism in traveling mode 9.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In the figure, the same reference numerals are used for the same or corresponding parts. Further, in each figure, the same elements are designated by the same reference numerals, and duplicate description will be omitted.

First, the configuration of the drive device 1 of the hybrid vehicle according to the embodiment will be described with reference to FIG. FIG. 1 is a skeleton diagram showing the configuration of a drive device 1 of a hybrid vehicle, and a block diagram showing the configuration of the control system thereof. Here, a case where the drive device 1 of the hybrid vehicle is applied to a series parallel hybrid vehicle (HEV) will be described as an example. The drive device 1 of the hybrid vehicle includes a power unit including an engine 20, a first motor generator 11, and a second motor generator 12, mainly a drive force dividing mechanism 30, a motor reduction gear 32, an output shaft 40, and a front drive pinion. It is equipped with a drive train (drive mechanism) including a shaft 50, a center differential unit 61, a propeller shaft 60, a rear drive pinion shaft 62, and the like. Hereinafter, it will be described in detail.

The engine 20 may be of any type, and for example, an engine whose thermal efficiency is improved by increasing the compression ratio by a high expansion ratio cycle is preferably used. The engine 20 is controlled by an engine control unit (hereinafter referred to as "ECU") 81.

Various sensors such as a crank angle sensor that detects the rotation position (engine rotation speed) of the crankshaft are connected to the ECU 81. The ECU 81 has a fuel injection amount, an ignition timing, an electronically controlled throttle valve, etc., based on these various acquired information and control information from the hybrid vehicle / control unit (hereinafter referred to as “HEV-CU”) 80 described later. The engine 20 is controlled by controlling various devices of the above. Further, the ECU 81 transmits various information such as the engine speed to the HEV-CU80 via the CAN (Control Area Network) 100.

A power split mechanism 30 is connected to the crankshaft of the engine 20 via a pair of gears 21. A pair of gears (counter gears) 31 and a first motor generator (MG) 11 are connected to the power split mechanism 30. The power split mechanism 30 has, for example, a planetary gear mechanism composed of a sun gear 30a, a ring gear 30b, a pinion gear 30c, and a planetary carrier 30d, and a pair of gears (counter gears) generate drive torque from the engine 20. The transmission is divided into 31 and the first motor generator 11.

More specifically, the carrier 30d is connected to the crankshaft of the engine 20 via a pair of gears 21. The sun gear 30a is connected to the first motor generator 11. On the other hand, the ring gear 30b is connected to the output shaft (output shaft) 40 via a pair of gears (counter gears) 31.

When the first motor generator 11 functions as a generator (generator), the power distribution mechanism 30 applies torque (driving force) from the engine 20 input from the planetary carrier 30d to both the sun gear 30a and the ring gear 30b. Distribute according to the ratio. On the other hand, in the power distribution mechanism 30, when the first motor generator 11 functions as a motor (motor), the torque from the engine 20 input from the planetary carrier 30d and the torque from the engine 20 input from the sun gear 30a are input to the first motor generator 11. Is integrated with the torque from the ring gear 30b and output to the ring gear 30b. The torque output to the ring gear 30b is output to the output shaft (output shaft) 40 via the pair of gears (counter gears) 31.

On the other hand, a second motor generator (MG) 12 is also connected to the output shaft (output shaft) 40. More specifically, the second motor generator 12 is connected to the output shaft (output shaft) 40 via the motor reduction gear 32.

The first motor generator 11 and the second motor generator 12 have a function as a motor that converts the supplied electric power into mechanical power and a function as a generator that converts the input mechanical power into electric power. It is configured as a synchronous power generator. That is, each of the first motor generator 11 and the second motor generator 12 operates as a motor that generates drive torque when the vehicle is driven, and operates as a generator during regeneration. The first motor generator 11 mainly operates as a generator, and the second motor generator 12 mainly operates as a motor.

The motor reduction gear 32 is composed of a planetary gear. More specifically, the motor reduction gear 32 has a planetary gear mechanism composed of, for example, a sun gear 32a, a ring gear 32b, a pinion gear 32c, and a planetary carrier 32d. When the second motor generator 12 functions as a motor, the motor reduction gear 32 reduces the rotation transmitted from the second motor generator 12 (increases the torque) and outputs the rotation from the planetary carrier 32d. On the other hand, the motor reduction gear 32 generates the second motor generator 12 by accelerating the rotation by the torque (driving force) input to the planetary carrier 32d and outputting it from the sun gear 32a (reducing the torque). To function as.

The output shaft (output shaft) 40 is a drive pinion shaft (front drive pinion shaft) 50 on the front wheel side via a first gear stage switching mechanism (auxiliary transmission) 71 (corresponding to the front wheel axle described in the claims). And connected to the propeller shaft 60 via the center differential unit 61. Further, the propeller shaft 60 corresponds to the drive pinion shaft (rear drive pinion shaft) 62 (rear wheel axle described in the claims) on the rear wheel side via the second gear stage switching mechanism (auxiliary transmission) 72. )It is connected to the. The output shaft (output shaft) 40 and the front drive pinion shaft 50 transmit torque to and from the front wheels. Further, the propeller shaft 60 and the rear drive pinion shaft 62 transmit torque to and from the rear wheels.

Here, the configuration of the first gear stage switching mechanism (auxiliary transmission) 71 will be described. First, the output shaft 40 and the front drive pinion shaft 50 are provided in parallel. First-speed and second-speed drive gears (drive gears) 711a and 712a are fixed to the tip of the output shaft 40. On the other hand, first-speed and second-speed driven gears (driven gears) 711b and 712b are rotatably attached to the rear end of the front drive pinion shaft 50. These drive gears 711a, 712a and driven gears 711b, 712b mesh with each other to form a transmission gear pair (shift stage). That is, the drive gear 711a and the driven gear 711b form the first gear pair 711, and the drive gear 712a and the driven gear 712b form the second gear pair 712. The gear ratio of the first gear pair 711 is lower than that of the second gear pair 712 when viewed from the second motor generator 12 (first motor generator 11) side (that is, when viewed from the front wheel side). High gear) is set.

The front drive pinion shaft 50 is connected to the first and second gears in a power transmission state and a neutral state (that is, the front drive pinion shaft 50 is connected to both the first gear pair 711 and the second gear pair 712. A first switching mechanism 713 (corresponding to the first switching means described in the claims) for switching to (not in the state of not being) is attached.

The first switching mechanism 713 is arranged between the two driven gears 711b and 712b of the first speed and the second speed, and is always meshed with the first hub 713a that rotates integrally with the front drive pinion shaft 50. It has one sleeve 713b. When the first sleeve 713b is meshed with the spline 711c integrally formed with the driven gear 711b, it is set to the first speed (low gear), and conversely, when it is meshed with the spline 712c integrally formed with the driven gear 712b, the second speed (high gear) is set. Is set to.

The first switching mechanism 713 is a synchromesh mechanism. That is, between the driven gear 711b (spline 711c) and the first sleeve 713b, and between the driven gear 712b (spline 712c) and the first sleeve 713b, a synchro mechanism (synchronizer ring) that synchronizes the rotations of both during the connection operation. ) Is provided.

In order to operate the first switching mechanism 713, the first sleeve 713b is gripped by a shift fork (not shown), and the first sleeve 713b moves in the axial direction as the shift fork moves. This shift fork is connected to the first actuator 714, and the desired shift stage is switched to the power transmission state by the movement of the first sleeve 713b accompanying the movement of the first actuator 714. The first switching mechanism 713 and the first actuator 714 function as the first switching means described in the claims. As the first actuator 714, for example, an electric motor or the like is preferably used. The first actuator 714 is driven and controlled by a transmission control unit (hereinafter referred to as “TCU”) 83, which will be described later.

The torque transmitted to the front drive pinion shaft 50 via the first gear stage switching mechanism 71 is transmitted to the front differential (hereinafter, also referred to as “front differential”) 53. The front differential 53 is, for example, a bevel gear type differential device. The torque from the front differential 53 is transmitted to the left front wheel (not shown) via the left front wheel drive shaft and to the right front wheel (not shown) via the right front wheel drive shaft.

On the other hand, as described above, the output shaft (output shaft) 40 is connected to the propeller shaft 60 via the center differential unit 61. Further, the propeller shaft 60 is connected to the rear drive pinion shaft 62 via a second gear stage switching mechanism (auxiliary transmission) 72.

Here, the center differential unit 61 mainly has, for example, a bevel gear that differentially absorbs the rotation difference between the front wheels (output shaft 40) and the rear wheels (propeller shaft 60), and for differential limitation (suppresses differential rotation). It is equipped with a transfer clutch. The transfer clutch controls the fastening force (that is, the torque distribution ratio to the rear wheels) according to the driving state of the four wheels (for example, the slip state of the front wheels, etc.) and the transmission torque. Therefore, the torque transmitted to the output shaft 40 is distributed according to the fastening force of the transfer clutch, and is also transmitted to the rear wheel side.

The torque adjusted (distributed) by the center differential unit (transfer clutch) 61 and transmitted to the propeller shaft 60 is transmitted to the rear drive pinion shaft 62 via the second gear stage switching mechanism 72.

Here, the configuration of the second gear stage switching mechanism 72 will be described. Similar to the first gear stage switching mechanism 71 described above, first, the propeller shaft 60 and the rear drive pinion shaft 62 are provided in parallel. First-speed and second-speed drive gears (drive gears) 721a and 722a are fixed to the tip of the propeller shaft 60. On the other hand, first-speed and second-speed driven gears (driven gears) 721b and 722b are rotatably attached to the rear end of the rear drive pinion shaft 62. These drive gears 721a, 722a and driven gears 721b, 722b mesh with each other to form a transmission gear pair (shift stage). That is, the drive gear 721a and the driven gear 721b form the first gear pair 721, and the drive gear 722a and the driven gear 722b form the second gear pair 722. The gear ratio of the first gear pair 721 is lower than that of the second gear pair 722 when viewed from the second motor generator 12 (first motor generator 11) side (that is, when viewed from the rear wheel side). Is set to high gear). Further, the gear ratio of each gear pair (first gear pair 711, second gear pair 712) constituting the first gear stage switching mechanism 71 and each gear pair constituting the second gear stage switching mechanism 72 (first gear pair). The gear ratios of the gear pair 721 and the second gear pair 722) are set to be the same.

The rear drive pinion shaft 62 has a second switching mechanism 723 (corresponding to the second switching means described in the claims) for switching the first and second speeds between the power transmission state and the neutral state. ) Is installed.

The second switching mechanism 723 is arranged between the two driven gears 721b and 722b of the first speed and the second speed, and is always meshed with the second hub 723a that rotates integrally with the rear drive pinion shaft 62. It has two sleeves 723b. When the second sleeve 723b is meshed with the spline 721c integrally formed with the driven gear 721b, it is set to the first speed (low gear), and conversely, when it is meshed with the spline 722c integrally formed with the driven gear 722b, the second speed (high gear) is set. Is set to.

The second switching mechanism 723 is a synchromesh mechanism. That is, between the driven gear 721b (spline 721c) and the second sleeve 723b, and between the driven gear 722b (spline 722c) and the second sleeve 723b, a synchro mechanism (synchronizer ring) that synchronizes the rotations of both during the connection operation. ) Is provided.

In order to operate the second switching mechanism 723, the second sleeve 723b is gripped by a shift fork (not shown), and the second sleeve 723b moves in the axial direction as the shift fork moves. This shift fork is connected to the second actuator 724, and the desired shift stage is switched to the power transmission state by the movement of the second sleeve 723b accompanying the movement of the second actuator 724. That is, the second switching mechanism 723 and the second actuator 724 function as the second switching means described in the claims. As the second actuator 724, for example, an electric motor or the like is preferably used. The second actuator 724 is driven and controlled by the TCU 83 described later.

The torque transmitted to the rear drive pinion shaft 62 via the second gear stage switching mechanism 72 is transmitted to the rear differential (hereinafter, also referred to as “rear differential”) 63. A left rear wheel drive shaft and a right rear wheel drive shaft (not shown) are connected to the rear differential 63. The driving force from the rear differential 63 is transmitted to the left rear wheel (not shown) via the left rear wheel drive shaft and to the right rear wheel (not shown) via the right rear wheel drive shaft.

The engine 20, the second motor generator 12, and the first motor generator 11, which are the driving force sources of the vehicle, are comprehensively controlled by the HEV-CU 80.

The HEV-CU80 includes, for example, an accelerator pedal sensor 91 that detects the amount of depression of the accelerator pedal, a throttle opening sensor 92 that detects the opening degree of the throttle valve, and a G sensor (accelerometer sensor) that detects the forward / backward / left / right acceleration of the vehicle. ) 93, and various sensors including a vehicle speed sensor 94 that detects the speed of the wheel are connected. Further, the HEV-CU 80 includes an ECU 81 that controls the engine 20 via a CAN 100, a vehicle dynamic control unit (hereinafter referred to as “VDCU”) 85 that suppresses side slip of the vehicle and improves running stability, and a TCU 83. Etc. are connected so that they can communicate with each other. The HEV-CU80 receives various information such as the engine speed and the brake operation amount from the ECU 81 and the VDCU85 via the CAN 100.

The HEV-CU 80 comprehensively controls the drive of the engine 20, the second motor generator 12, and the first motor generator 11 based on these various acquired information. The HEV-CU 80 includes, for example, an accelerator pedal opening (driver's required driving force), a vehicle operating state (vehicle speed, etc.), a high-voltage battery (hereinafter, also simply referred to as “battery”) 90, and a state of charge (SOC). The required output of the engine 20 and the torque command values of the second motor generator 12 and the first motor generator 11 are obtained and output based on the above.

The ECU 81 adjusts, for example, the opening degree of the electronically controlled throttle valve based on the required output. Further, the power control unit (hereinafter referred to as “PCU”) 82 drives the second motor generator 12 and the first motor generator 11 based on the torque command value. Here, the PCU 82 has an inverter 82a that converts the DC power of the high voltage battery 90 into three-phase AC power and supplies it to the second motor generator 12 and the first motor generator 11. The PCU 82 drives the second motor generator 12 and the first motor generator 11 via the inverter 82a based on the torque command value received from the HEV-CU 80. On the other hand, the inverter 82a converts the AC voltage generated by the second motor generator 12 into a DC voltage at the time of regeneration to charge the high voltage battery 90.

Further, the HEV-CU 80 has a first gear stage based on, for example, an accelerator pedal opening (driver's required driving force), a vehicle operating state (vehicle speed, etc.), a high-voltage battery 90 charging state (SOC), and the like. The switching instruction information of the shift stage (gear ratio) of the switching mechanism 71 and the switching instruction information of the shift stage (gear ratio) of the second gear stage switching mechanism 72 are set and transmitted to the TCU 83. The TCU 83 drives the first actuator 714 based on the shift instruction information of the shift stage (gear ratio) of the first gear stage switching mechanism 71 transmitted from the HEV-CU 80, and also shifts the shift of the second gear stage switching mechanism 72. The second actuator 724 is driven based on the switching instruction information of the stage (gear ratio).

Each of the HEV-CU80 and TCU83 holds a microprocessor that performs an operation, an EEPROM that stores a program for causing the microprocessor to execute each process, a RAM that stores various data such as calculation results, and the stored contents thereof. It is configured to have a backup RAM, input / output I / F, and the like. The TCU 83 also includes a drive circuit (driver circuit) for driving the first actuator 714 and the second actuator 724.

In particular, the HEV-CU80 and TCU83 can increase the amount of regeneration during regeneration without lowering the drive torque during drive (without deteriorating drivability) (the overall efficiency of the vehicle (drive device) can be improved). It has a function to further improve the fuel consumption rate (fuel efficiency). Therefore, the HEV-CU 80 has a functional switching control unit 80a that sets switching instruction information for the shift stage (gear ratio) of the first gear stage switching mechanism 71 and the shift stage (gear ratio) of the second gear stage switching mechanism 72. Have in. In the HEV-CU80, the function of the switching control unit 80a is realized by executing the program stored in the EEPROM or the like by the microprocessor. Similarly, the TCU 83 functionally has a drive control unit 83a that controls the drive of the first actuator 714 and the second actuator 724. In the TCU 83, the function of the drive control unit 83a is realized by executing the program stored in the EEPROM or the like by the microprocessor. That is, the HEV-CU 80 (switching control unit 80a) and the TCU 83 (drive control unit 83a) function as the control means described in the claims.

The switching control unit 80a and the drive control unit 83a are the first actuator 714 (first switching means 713) and the second actuator based on the operating state of the vehicle (for example, drive required force (accelerator pedal operation), vehicle speed, SOC, etc.). It controls the drive of the actuator 724 (second switching mechanism 723).

For example, the switching control unit 80a and the drive control unit 83a have a plurality of (two pairs) of gear pairs 711 and 712 constituting the first gear stage switching mechanism 71 when the accelerator operation is off (during coasting). Among them, the first gear pair 711, which is higher gear (low gear when viewed from the second motor generator 12 (first motor generator 11) side) when viewed from the front wheel side, is switched (selected). Similarly, of the plurality (2 pairs) of gear pairs 721 and 722 constituting the second gear stage switching mechanism 72, the higher gear (second motor generator 12 (first motor generator 11)) is seen from the rear wheel side. ) Switch to (select) the first gear pair 721, which is low gear when viewed from the side. Details will be described later.

The switching control unit 80a and the drive control unit 83a move the first sleeve 713b to switch the gear pair connected to the front drive pinion shaft 50 among the plurality of (2 pairs) gear pairs 711 and 712. The second motor generator 12 (first motor) is set so that the first switching means 713 is temporarily in the neutral state and the rotation speed of the connected gear pair is matched with the rotation speed of the front drive pinion shaft 50. -It is preferable to control the rotation speed of the generator 11). Similarly, when the switching control unit 80a and the drive control unit 83a move the second sleeve 723b to switch the gear pair connected to the rear drive pinion shaft 62 among the plurality (2 pairs) of gear pairs 721 and 722. , The second motor generator 12 (first) so that the second switching mechanism 723 is temporarily set to the neutral state and the rotation speed of the connected gear pair is matched with the rotation speed of the rear drive pinion shaft 62. It is preferable to control the rotation speed of the motor / generator 11).

Here, each traveling mode realized by the configuration as described above will be described with reference to FIGS. 2 to 9. FIG. 2 is a list showing the traveling modes that can be taken in the drive device 1 of the hybrid vehicle. 3 to 6 are diagrams showing torque transmission paths (thick lines) via the first gear stage switching mechanism 71 and the second gear stage switching mechanism 72 in each of the traveling modes 1 to 4. Similarly, FIGS. 7 to 10 are diagrams showing torque transmission paths (thick lines) via the first gear stage switching mechanism 71 and the second gear stage switching mechanism 72 in each of the traveling modes 6 to 9. The torque transmission path (thick line) in the traveling mode 4 is shown in FIG.

(1) Mode 1
In mode 1, as shown in FIG. 3, the first gear stage switching mechanism 71 is set to low gear (first gear pair 711 is selected), and the second gear stage switching mechanism 72 is set to low gear (first gear pair 721). Is selected), and it is an AWD (all-wheel drive) mode in which all wheels are driven. This mode is selected, for example, during normal starting, low-speed driving, acceleration, and the like. Then, for example, when the speed increases (during high-speed driving), the mode 2 is switched to the mode 2 described later. On the other hand, at the time of deceleration, the rotation speed of the second motor generator 12 (first motor generator 11) can be increased to perform regeneration as compared with the mode 2 described later. However, for example, considering the operating state (running state) of the vehicle, the operating efficiency of each of the engine 10, the first motor, the generator 11, the second motor, and the generator 12, and the drag loss of the drive system, etc., the total vehicle The driving mode may be switched to modes 2, mode 5, modes 6, 7, and modes 8 and 9, which will be described later, so as to maximize efficiency.

(2) Mode 2
In mode 2, as shown in FIG. 4, the first gear stage switching mechanism 71 is set to high gear (second gear pair 712 is selected), and the second gear stage switching mechanism 72 is set to high gear (second gear pair 722). Is selected), and it is an AWD (all-wheel drive) mode in which all wheels are driven. This mode is selected, for example, when traveling at high speed. Then, for example, when the speed is reduced (during low speed running) or when the accelerator pedal is greatly depressed (during sudden acceleration), the mode 1 can be switched to the above-mentioned mode 1. On the other hand, during deceleration, regeneration may be performed in this mode, but when the rotation speed of the second motor generator 12 (first motor generator 11) is increased, the mode is switched to the above-mentioned mode 1. However, for example, considering the operating state (running state) of the vehicle, the operating efficiency of each of the engine 10, the first motor, the generator 11, the second motor, and the generator 12, and the drag loss of the drive system, etc., the total vehicle The driving mode may be switched to modes 5, modes 6, 7, and modes 8 and 9, which will be described later, so as to maximize efficiency.

(3) Mode 3
In mode 3, as shown in FIG. 5, the first gear stage switching mechanism 71 is set to low gear (first gear pair 711 is selected), and the second gear stage switching mechanism 72 is set to high gear (second gear pair 722). Is selected), and it is an AWD (all-wheel drive) mode in which all wheels are driven. This mode is not used in normal driving, and is selected when traveling by utilizing the differential rotation and the differential torque of the front and rear wheels, for example, on an uphill road or when turning.

(4) Mode 4
In mode 4, as shown in FIG. 6, the first gear stage switching mechanism 71 is set to high gear (second gear pair 712 is selected), and the second gear stage switching mechanism 72 is set to low gear (first gear pair 721). Is selected), and it is an AWD (all-wheel drive) mode in which all wheels are driven. This mode is not used in normal driving, and is selected when traveling by utilizing the differential rotation and the differential torque of the front and rear wheels, for example, on an uphill road or when turning.

(5) Mode 5
As shown in FIG. 1, the mode 5 is a mode in which the first gear stage switching mechanism 71 is set to neutral (neutral) and the second gear stage switching mechanism 72 is set to neutral (neutral). This mode is selected, for example, to reduce the drag loss during deceleration. In particular, this mode is selected during coasting, for example, where the SOC of the high voltage battery 90 is sufficient and regeneration cannot be achieved.

(6) Mode 6
In mode 6, as shown in FIG. 7, the first gear stage switching mechanism 71 is set to low gear (first gear pair 711 is selected), and the second gear stage switching mechanism 72 is set to neutral (neutral). This is an FF (front wheel drive) mode in which the front wheels are driven. This mode is selected, for example, when starting, traveling at low speed, accelerating, and the like. Then, for example, when the speed increases (during high-speed driving), the mode is switched to the mode 7 described later. On the other hand, during deceleration, regeneration can be performed by increasing the rotation speed of the second motor generator 12 (first motor generator 11) while reducing the drag loss on the rear wheel side.

(7) Mode 7
In mode 7, as shown in FIG. 8, the first gear stage switching mechanism 71 is set to high gear (second gear pair 712 is selected), and the second gear stage switching mechanism 72 is set to neutral (neutral). This is an FF (front wheel drive) mode in which the front wheels are driven. This mode is selected, for example, when traveling at high speed. Then, for example, when the speed decreases (during low speed running) or when the vehicle accelerates suddenly, the mode 6 can be switched to the above-mentioned mode 6. On the other hand, during deceleration, regeneration can be performed while reducing the drag loss on the rear wheel side. When the rotation speed of the second motor generator 12 (first motor generator 11) is increased during regeneration, the mode 6 is switched to the above-mentioned mode 6.

(8) Mode 8
In mode 8, as shown in FIG. 9, the first gear stage switching mechanism 71 is set to neutral (neutral), and the second gear stage switching mechanism 72 is set to low gear (first gear pair 721 is selected). This is the FR (rear wheel drive) mode in which the rear wheels are driven. This mode is selected, for example, when starting, traveling at low speed, accelerating, and the like. Then, for example, when the speed increases (during high-speed driving), the mode 9 is switched to the mode 9 described later. On the other hand, during deceleration, regeneration can be performed by increasing the rotation speed of the second motor generator 12 (first motor generator 11) while reducing the drag loss on the front wheel side.

(9) Mode 9
In the mode 9, as shown in FIG. 10, the first gear stage switching mechanism 71 is set to neutral (neutral), and the second gear stage switching mechanism 72 is set to high gear (second gear pair 722 is selected). This is the FR (rear wheel drive) mode in which the rear wheels are driven. This mode is selected, for example, when traveling at high speed. Then, for example, when the speed decreases (during low speed running) or when the vehicle accelerates suddenly, the mode 8 can be switched to the above-mentioned mode 8. On the other hand, during deceleration, regeneration can be performed while reducing the drag loss on the front wheel side. When the rotation speed of the second motor generator 12 (first motor generator 11) is increased during regeneration, the mode 8 is switched to the above-mentioned mode 8.

As described in detail above, according to the present embodiment, the front drive pinion shaft 50 is interposed, has a plurality of (2 pairs) gear pairs 711,712, and converts the input torque / rotation speed. It is interposed in the first gear stage switching mechanism 71 and the rear drive pinion shaft 62, and has a plurality of (2 pairs) gear pairs 721 and 722, and converts the input torque / rotation speed to output. The front drive pinion shaft 50 is provided among the plurality (2 pairs) of gear pairs 711 and 712 constituting the first gear stage switching mechanism 71 based on the operating state of the vehicle. The gear pairs to be connected are switched, and among the plurality (2 pairs) of gear pairs 721 and 722 constituting the second gear stage switching mechanism 72, the gear pair connected to the rear drive pinion shaft 62 is switched. Therefore, for example, the gear ratios of the first gear stage switching mechanism 71 and the second gear stage switching mechanism 72 can be switched between driving and regeneration. That is, during driving (acceleration), a gear pair with a gear ratio suitable for driving (acceleration) can be used, and during regeneration, a gear pair with a gear ratio suitable for regeneration (good regeneration efficiency) can be used. As a result, the amount of regeneration during regeneration can be increased without reducing the driving torque during driving, and fuel efficiency can be further improved.

According to the present embodiment, the gear ratio of each gear pair 711,712 included in the first gear stage switching mechanism 71 and the gear ratio of each gear pair 721,722 included in the second gear stage switching mechanism 72. However, they are set to be the same. Therefore, it is possible to prevent an unnecessary rotation difference from occurring between the front wheels and the rear wheels.

According to the present embodiment, by moving the first sleeve 713b and switching the gear pair connected to the first hub 713a, a plurality of (two pairs) of gear pairs 711,712 constituting the first gear stage switching mechanism 71 are used. Of these, the gear pair connected to the front drive pinion shaft 50 is switched. Therefore, by driving the first actuator 713 and sliding the first sleeve 713b, the gear ratio (final gear ratio) on the front wheel side can be switched. Similarly, by moving the second sleeve 723b and switching the gear pair connected to the second hub 723a, the rear of the plurality (two pairs) of the gear pairs 721 and 722 constituting the second gear stage switching mechanism 72. The gear pair connected to the drive pinion shaft 62 is switched. Therefore, by driving the second actuator 724 and sliding the second sleeve 723b, the gear ratio (final gear ratio) on the rear wheel side can be switched.

According to the present embodiment, when the accelerator operation is turned off, among the plurality (2 pairs) of gear pairs 711 and 712 constituting the first gear stage switching mechanism 71, the higher gear is seen from the front wheel side. It can be switched to the gear pair 711, and can be switched to the higher gear pair 721 when viewed from the rear wheel side among the plurality (2 pairs) of the gear pairs 721 and 722 constituting the second gear stage switching mechanism 72. Therefore, for example, when the vehicle is in the coasting state, the rotation speed of the second motor generator 12 (first motor generator 11) can be increased, that is, the regeneration efficiency can be increased to execute the regeneration operation. ..

According to the present embodiment, the first switching mechanism 713 is in a neutral state in which the front drive pinion shaft 50 is not connected to any of the gear pairs 711 and 712, thereby blocking the torque transmission with the front wheels ( The front wheel can be separated) to reduce drag loss. Further, by setting the second switching mechanism 723 in a neutral state in which the rear drive pinion shaft 62 is not connected to any of the gear pairs 721 and 722, the torque transmission with the rear wheels is cut off (the rear wheels are separated). ), The drag loss can be reduced. Further, for example, when the charge / charge state (SOC) of the battery 90 is sufficient (that is, the battery 90 cannot be charged) and regeneration cannot be performed, all the front wheels and the rear wheels are separated to reduce the drag loss. You can also do it. That is, the vehicle is driven in an AWD (all-wheel drive) state, an FF (front wheel drive) state in which the rear wheels are separated, an FR (rear wheel drive) state in which the front wheels are separated, and N in which all wheels are separated. You can switch between (neutral: neutral) states. Therefore, the drive type and front drive pinion so that the efficiency of the vehicle (drive device) is the best as a whole according to the driving state of the vehicle (for example, required driving force (accelerator opening), vehicle speed, SOC, etc.). It is possible to switch the gear ratio (final gear ratio) of the shaft 50 and the gear ratio (final gear ratio) of the rear drive pinion shaft 62.

According to the present embodiment, between the driven gear 711b (spline 711c) and the first sleeve 713b included in the first gear stage switching mechanism 71, and between the driven gear 712b (spline 712c) and the first sleeve 713b. Since a synchro mechanism that synchronizes both rotations is provided, the first hub 713a (first sleeve 713b) is used when the first sleeve 713b is fitted with the splines 711c and 712c provided on the driven gears 711b and 712b. And even when the rotational speeds of the driven gears 711b and 712b are different, the first sleeve 713b and the splines 711c and 712c provided on the driven gears 711b and 712b can be connected more smoothly. Similarly, the rotation of both of the driven gear 721b (spline 721c) and the second sleeve 723b included in the second gear stage switching mechanism 72 and between the driven gear 722b (spline 722c) and the second sleeve 723b. When the second sleeve 723b is fitted with the splines 721c and 722c provided on the driven gears 721b and 722b, the second hub 723a (second sleeve 723b) and the driven gear 721b, Even when the rotation speeds of the 722b are different, the second sleeve 723b and the splines 721c and 722c provided on the driven gears 721b and 722b can be connected more smoothly.

According to the present embodiment, when the first sleeve 713b is moved to switch the gear pair connected to the front drive pinion shaft 50, the first switching mechanism 713 is temporarily set to the neutral state, and the connected gear pair is set. The rotation speed of the second motor generator 12 (first motor generator 11) is controlled so as to match the rotation speed of the front drive pinion shaft 50 with the rotation speed of the front drive pinion shaft 50. Therefore, it is possible to reduce the shock (switching shock) when switching the gear pairs 711 and 712. Similarly, when the second sleeve 723b is moved to switch the gear pair connected to the rear drive pinion shaft 62, the second switching mechanism 723 is temporarily in the neutral state, and the rotation speed of the connected gear pair is set. , The rotation speed of the second motor generator 12 (first motor generator 11) is controlled so as to match the rotation speed of the rear drive pinion shaft 62. Therefore, it is possible to reduce the shock (switching shock) when switching between the gear pairs 721 and 722.

Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment and can be modified in various ways. For example, in the above embodiment, the case where the power regenerative device 1 according to the present invention is applied to a series parallel hybrid electric vehicle (HEV) has been described as an example, but it can also be applied to a different type of hybrid vehicle. ..

Further, in the above embodiment, two electric motors (first motor generator 11 and second motor generator 12) are provided, but the number of electric motors is not limited to two (two motors), and one. It may be one (1 motor) or three (3 motors) or more. Similarly, the configuration of the hybrid system is not limited to the above embodiment.

In the above embodiment, the case of two-speed shifting having two pairs of gear pairs 711,712 (721,722) as the first gear stage switching mechanism 71 and the second gear stage switching mechanism 72 has been described as an example. The first gear stage switching mechanism 71 and the second gear stage switching mechanism 72 are not limited to the two-speed shift (two pairs of gear pairs), and may have a configuration of three-speed shift or more having three or more pairs of gears. ..

In the above embodiment, as the first actuator 714 and the second actuator 724, an electric motor (electric motor) is used, but a hydraulic actuator can also be used. Further, for example, the HEV-CU80 and the TCU83 may be integrated.

1 Hybrid vehicle drive device 11 1st motor generator 12 2nd motor generator 20 engine 30 driving force splitting mechanism 32 motor reduction gear 40 output shaft 50 front drive pinion shaft 53 front differential 60 propeller shaft 61 center differential unit 62 rear Drive pinion shaft 63 Rear differential 71 1st gear stage switching mechanism 711 1st gear pair 712 2nd gear pair 713 1st switching mechanism 713a 1st hub 713b 1st sleeve 714 1st actuator 72 2nd gear stage switching mechanism 721 1st Gear pair 722 Second gear pair 723 Second switching mechanism 723a Second hub 723b Second sleeve 724 Second actuator 80 HEV-CU
80a Switching control unit 81 ECU
82 PCU
83 TCU
83a Drive control unit 85VDCU
90 High voltage battery 91 Accelerator pedal sensor 92 Throttle opening sensor 93 G sensor (accelerometer)
94 Vehicle speed sensor (wheel speed sensor)
95 rpm sensor 100 CAN

Claims (7)

In the drive unit of a hybrid vehicle equipped with an engine and a motor generator
A front wheel axle that transmits torque between the engine, the motor generator, and the front wheels.
A rear wheel axle that transmits torque between the engine, the motor generator, and the rear wheels.
A center differential unit provided between the motor generator and the rear wheel and absorbing a rotational difference between the front wheel axle and the rear wheel axle.
A first gear stage switching mechanism that is interposed on the front wheel axle, has a plurality of gear pairs, converts the input torque, and outputs the torque.
The second gear stage switching, which is interposed in the rear wheel axle and has a plurality of gear pairs having the same number as the plurality of gear pairs constituting the first gear stage switching mechanism, converts the input torque and outputs it. Mechanism and
A first switching means for switching a gear pair connected to the front wheel axle among a plurality of gear pairs constituting the first gear stage switching mechanism.
A second switching means for switching a gear pair connected to the rear wheel axle among a plurality of gear pairs constituting the second gear stage switching mechanism.
A driving device for a hybrid vehicle, comprising: a control means for controlling the driving of the first switching means and the second switching means based on the driving state of the vehicle. A claim characterized in that the gear ratio of each gear pair included in the first gear stage switching mechanism and the gear ratio of each gear pair included in the second gear stage switching mechanism are all set to be the same. Item 1. The drive device for a hybrid vehicle according to item 1. When the accelerator operation is turned off, the control means switches to a gear pair having a higher gear when viewed from the front wheel side among the plurality of gear pairs constituting the first gear stage switching mechanism, and the second gear pair. The drive device for a hybrid vehicle according to claim 1 or 2, wherein the gear pair is switched to a gear pair having a higher gear when viewed from the rear wheel side among a plurality of gear pairs constituting the gear stage switching mechanism. The first switching means is
A first hub that rotates integrally with the front wheel axle,
A first sleeve provided on the outer periphery of the first hub so as to be slidable in the axial direction,
Among the plurality of gear pairs, there is a first actuator that switches the gear pair connected to the front wheel axle by sliding the first sleeve and switching the gear pair connected to the first hub. death,
The second switching means is
A second hub that rotates integrally with the rear wheel axle,
A second sleeve provided on the outer periphery of the second hub so as to be slidable in the axial direction,
A second actuator that switches the gear pair connected to the rear wheel axle among the plurality of gear pairs by sliding the second sleeve and switching the gear pair connected to the second hub. The drive device for a hybrid vehicle according to any one of claims 1 to 3, wherein the hybrid vehicle is provided. The first switching means is configured to take a neutral state in which the front wheel axle is not connected to any gear pair.
The driving device for a hybrid vehicle according to claim 4, wherein the second switching means is configured so that the rear wheel axle can take a neutral state in which the rear wheel axle is not connected to any gear pair. A synchro mechanism for synchronizing the rotation of both gears is provided between one of the gears constituting each gear pair included in the first gear stage switching mechanism and the first hub.
The claim is characterized in that a synchro mechanism for synchronizing the rotations of both gears and the second hub, which form one gear pair included in the second gear stage switching mechanism, is provided. 4. The drive device for a hybrid vehicle according to 4. The control means is
When the first sleeve is moved to switch the gear pair connected to the front wheel axle, the first switching means is temporarily set to the neutral state, and the rotation speed of the connected gear pair is set to the rotation speed of the front wheel axle. The rotation speed of the motor / generator is controlled so as to match the number.
When the second sleeve is moved to switch the gear pair connected to the rear wheel axle, the second switching means is temporarily set to the neutral state, and the rotation speed of the connected gear pair is set to the rear wheel axle. The drive device for a hybrid vehicle according to claim 5 or 6, wherein the rotation speed of the motor / generator is controlled so as to match the rotation speed of the motor / generator.

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