JP2021030771A - Hybrid vehicle - Google Patents

Abstract

To achieve comfortable travel for a driver when an engine is driven in a hybrid vehicle in which a first wheel is driven by an engine and a second wheel is driven by a motor.SOLUTION: A hybrid vehicle 10 can execute at least one support among: regenerative support that uses a regenerative brake of a motor 22 during deceleration on a down-hill; slip support that returns from slip to a slip-free state with drive power of the motor when a first wheel slips; sudden acceleration support that adds drive power of the motor to drive power of an engine 21 and accelerates; slope support that drives the motor so that up-slope approach speed and upslope passage speed become equal.SELECTED DRAWING: Figure 2

Description

The present invention relates to a hybrid vehicle including an engine for driving a first wheel and a motor for driving a second wheel separated from the first wheel in the front-rear direction. And switching to the proper charging mode for the battery and / or both.

Conventionally, as described in Patent Document 1, a hybrid vehicle in which the front wheels are driven by an engine and the left and right rear wheels are driven by a pair of left and right motors has been described. In this vehicle, when the operation amount of the accelerator pedal (acceleration instruction unit) is 0 and the operation amount of the brake pedal is less than a predetermined value, the motor creeps the vehicle. If the operating amount of the accelerator pedal is other than 0, the driving force of the engine is assisted by the driving of the motor, and the assist by the motor ends as the operating amount of the accelerator pedal increases. It is said that this can minimize the use of areas with poor energy efficiency and contribute to the reduction of fuel efficiency.

Japanese Unexamined Patent Publication No. 10-75505

By the way, in a hybrid vehicle in which the first wheel is driven by an engine and the second wheel is driven by a motor, it is desired that the driver realize comfortable driving when the engine is driven. It is also desired that the battery that supplies power to the motor can be switched to an appropriate charging mode.

An object of the present invention is to enable a driver to drive comfortably when the engine is driven in a hybrid vehicle in which the first wheel is driven by an engine and the second wheel is driven by a motor, and to appropriately charge the battery. It is at least one of enabling switching to a mode.

The first hybrid vehicle according to the present invention includes an engine for driving the first wheel and a motor for driving the second wheel separated from the first wheel in the front-rear direction, and the motor during deceleration on a downhill. A regenerative support that utilizes the regenerative brake of the engine, a slip support that returns the slip to a non-slip state by the driving force of the motor when the first wheel slips, and a driving force of the motor added to the driving force of the engine. Of the sudden acceleration support that accelerates and the slope support that drives the motor so that the approach speed to the uphill and the passing speed of the uphill are equal, at least one support can be executed when the engine is driven. There is a hybrid vehicle.

Further, the second hybrid vehicle according to the present invention is driven by an engine that drives the first wheel, a motor that is connected to a battery and drives a second wheel that is separated from the first wheel in the front-rear direction, and the engine. A low-power charging mode in which the battery is charged and the battery is charged, a high-power charging mode in which the battery is charged and the charging speed of the battery is higher than that of the low-power charging mode, and the above. It is a hybrid vehicle that is configured to be switchable between a charge stop mode that stops charging the battery.

Further, the third hybrid vehicle according to the present invention is driven by an engine that drives the first wheel, a motor that is connected to a battery and drives a second wheel that is separated from the first wheel in the front-rear direction, and the engine. It is provided with a generator for charging the battery, and when the engine is driven and the vehicle is stopped, a low power charging mode for charging the battery and a charging speed for charging the battery and charging the battery are set. One of the high power charging modes higher than the low power charging mode can be executed, and when traveling, the regenerative support using the regenerative brake of the motor when decelerating downhill and the motor when the first wheel slips. Slip support that returns from slip to a slip-free state with the driving force of, sudden acceleration support that accelerates by adding the driving force of the motor to the driving force of the engine, approach speed to the uphill and passing speed of the uphill It is a hybrid vehicle capable of executing at least one support among the slope supports for driving the motor so that the two are substantially equal to each other.

According to the first and third hybrid vehicles according to the present invention, in a hybrid vehicle in which the first wheel is driven by an engine and the second wheel is driven by a motor, the driver can drive comfortably when the engine is driven. realizable. According to the second and third hybrid vehicles according to the present invention, in a hybrid vehicle in which the first wheel is driven by an engine and the second wheel is driven by a motor, the battery can be switched to an appropriate charging mode. Become.

FIG. 5 is a side view showing a part of the hybrid vehicle of the embodiment according to the present invention in cross section. It is a figure which shows the whole structure of the moving body drive unit mounted on the vehicle of FIG. FIG. 2 is a diagram showing a group of operating elements connected to the control device in FIG. FIG. 2 is an enlarged view of part A including a centrifugal clutch in FIG. It is a figure which shows the structure of the drive circuit of the electric motor, and the control device in the Embodiment which concerns on this invention. It is a figure which shows the 1st display area which has a plurality of traveling mode selection parts in the operation panel of FIG. It is a figure which shows the 2nd display area which has a plurality of support selection part in the operation panel of FIG. It is a figure which shows the 3rd display area which has a plurality of charge mode selection part in the operation panel of FIG. It is a figure which shows the state which the hybrid vehicle shifts from running on a flat road to running on a downhill, and the state where regenerative support is executed when running on a downhill. It is a figure which shows the relationship between the regenerative torque of an electric motor, the vehicle speed and the inclination angle of a downhill slope in the control when a regenerative support is selected. It is a figure which shows the relationship between the transition from the normal straight running state to the rear wheel slip state, the rear wheel grip restoration state, and the front wheel rotation speed and the rear wheel rotation speed in each state in the control when a slip support is selected. It is a figure which shows the relationship between the accelerator opening degree and engine torque in control at the time of slip support selection. It is a figure which shows the relationship between the elapsed time and the motor torque in control at the time of slip support selection. It is a figure which shows the relationship between the accelerator opening and the motor torque in control at the time of sudden acceleration support selection. It is a figure which shows the time passage of the vehicle driving force and the vehicle speed when the accelerator opening degree is constant in the control when a sudden acceleration support is selected. It is a figure which shows the vehicle position (a) when traveling on a flat road, the vehicle position (b) at the start of a slope support, and the vehicle position (c) when the target vehicle speed is reached by executing the slope support. In the embodiment, it is a flowchart which shows the switching method of the charge mode of a battery. It is a flowchart which shows the control method at the time of starting support selection in the Embodiment which concerns on this invention. In the embodiment of the present invention, it is a figure which shows the example of a plurality of switching between a slow start support, a sudden start support, and a smooth start support when a start support is selected. It is a figure which shows the switching condition of the support in FIG. It is a figure which shows the relationship between the accelerator opening degree and a motor torque in a slow start support. It is a figure which shows the relationship between the accelerator opening degree and engine torque in a sudden start support. It is a figure which shows the relationship between the accelerator opening degree and a motor torque in a sudden start support. It is a figure which shows the motor operation, the engine operation, and the switching timing to the next stage in smooth start support. It is a figure which shows the time passage of a vehicle driving force, a vehicle speed, and an engine rotation speed when the accelerator opening degree is constant in a smooth start support. It is a figure which shows the relationship between the accelerator opening and the motor torque at the initial stage of a start in a smooth start support. It is a figure which shows the relationship between the elapsed time, the vehicle speed, and the engine torque in the 1st stage of the mid-starting period in a smooth start support. It is a figure which shows the relationship between the accelerator opening degree and a vehicle speed, and a motor torque in the 2nd stage of a mid-starting period in a smooth start support. It is a flowchart which shows the switching method of the charge mode of a battery in another example of the Embodiment which concerns on this invention. It is a side view of the hybrid vehicle of another example of embodiment which concerns on this invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following, the case where the moving body equipped with the moving body driving unit is an off-road utility vehicle or a tractor having a loading platform and traveling on rough terrain such as forests, wastelands, and rocky mountains will be described. , A work vehicle having a work machine that performs any one or more of snow removal work, excavation work, civil engineering work, and agricultural work, or an All Terrain Vehicle (ATV) or a Recreational Vehicle (ROV). In the following, similar elements will be described with the same reference numerals in all drawings.

1 to 25 show embodiments. FIG. 1 is a side view showing a part of the hybrid vehicle 10 of the embodiment as a cross section. FIG. 2 is a diagram showing an overall configuration of a mobile body drive unit mounted on the hybrid vehicle 10. FIG. 3A is a diagram showing a group of operating elements connected to the control device in FIG. FIG. 3B is an enlarged view of part A including the centrifugal clutch in FIG. FIG. 4 is a diagram showing a configuration of a drive circuit and a control device of an electric motor.

The hybrid vehicle 10 shown in FIG. 1 is an off-road type multipurpose vehicle having a loading platform 19, and includes an engine 21 for driving two left and right rear wheels 16 and a motor 22 for driving two left and right front wheels 15. Will be done. Hereinafter, the hybrid vehicle 10 may be referred to as a vehicle 10. The motor 22 is an electric motor. The front wheels 15 are separated from the rear wheels 16 in the front-rear direction (left-right direction in FIG. 1). The rear wheel 16 corresponds to the first wheel, and the front wheel 15 corresponds to the second wheel. Specifically, the platform 12 which is a basic structure is fixed on the upper side of the frame 11 constituting the vehicle body, and the front cover 13 is fixed on the front side (right side in FIG. 1) of the frame 11. In the platform 12, the driver's seat 14 is fixed to the rear side of the front cover 13, and the loading platform 19 is fixed to the rear side of the driver's seat 14. The vehicle 10 includes two left and right front wheels 15 and two left and right rear wheels 16 which are wheels supported in the front and rear of the frame 11, an operating element group 18, and a moving body drive unit 20. As shown in FIG. 1, the battery 23 described later is located below the driver's seat 14 and inside the frame portion in the front-rear direction intermediate portion of the frame 11.

The moving body drive unit 20 has two power sources, an engine 21 and a motor 22, a battery 23 (FIGS. 1 and 2) as a power source, and two for generating electricity driven by the engine 21 and stored in the battery 23. Generators GE1 and GE2 (FIG. 2), rear power transmission unit 25 (FIG. 2), front power transmission unit 41 (FIG. 2), sensor switch group 50 (FIG. 2), and control device 70 (FIG. 2). including. As shown in FIG. 2, the generator GE1 has a rotor fixed to the output shaft 21a of the engine 21 and a stator facing the rotor. The generator GE2 is connected so that the power of the engine 21 is transmitted via the output shaft 21b extending to the side opposite to the CVT 26 of the engine 21 and the belt pulley mechanism 21c. The generators GE1 and GE2 are controlled by the inverter 24b, and the generated electric power is charged into the battery 23. One of the two generators GE1 and GE2 may be omitted. A battery monitoring module (BCM) 65 that detects the temperature and voltage of the battery 23 is attached to the battery 23. The battery monitoring module 65 corresponds to a charge monitoring unit. The battery monitoring module 65 also has a function of detecting the charge amount which is the remaining charge of the battery 23. The charge amount detection signal from the battery monitoring module 65 is transmitted to the control device 70. Further, the vehicle 10 is provided with an inclination angle sensor 66 to detect the inclination angle of the road surface on which the vehicle 10 is located with respect to the horizontal plane. The detection signal of the tilt angle sensor 66 is also transmitted to the control device 70.

Further, the vehicle 10 has (1) slow start support, (2) sudden start support, and (3) smooth start support. (1) The slow start support drives the vehicle 10 only with the motor 22 as a drive source at the time of starting. (2) The sudden start support drives the vehicle 10 by the engine 21 and the motor 22 as a drive source at the time of starting. (3) For smooth start support, the vehicle 10 is driven only by the motor 22 as a drive source in the initial stage of starting, the vehicle 10 is driven by the engine 21 and the motor 22 as drive sources in the middle stage, and only the engine 21 is driven as a drive source in the latter stage. Drives the vehicle 10. When the operation amount of the accelerator pedal 60, which will be described later, is not 0, the vehicle 10 can be either (1) slow start support, (2) sudden start support, or (3) smooth start support depending on the operation status of the accelerator pedal 60. Is configured to be executed. Even when the operation amount of the accelerator pedal 60 is 0, either (1) slow start support or (2) sudden start support may be executed. The accelerator pedal 60 corresponds to an acceleration indicator. As a result, when the small motor 22 is used in the vehicle 10, it is possible to realize a starting performance close to the driver's intention according to the driving situation, and to improve the energy efficiency and the durability of the motor 22.

Further, the vehicle 10 can execute at least one of (A) regenerative support, (B) slip support, (C) sudden acceleration support, and (D) slope support when the engine 21 is driven. Is. (A) The regenerative support uses the regenerative brake of the motor 22 when decelerating the downhill of the vehicle 10. (B) The slip support returns the slip to a slip-free state by the driving force of the motor 22 when the rear wheels 16 slip. (C) The sudden acceleration support accelerates by adding the driving force of the motor 22 to the driving force of the engine 21. (D) The slope support drives the motor 22 so that the approach speed to the uphill and the passing speed of the uphill are equal to each other. For example, (A) regenerative support, (B) slip support, (C) sudden acceleration support, and (D) slope support are selected and instructed by the driver by touching the operation panel 52 described later. be able to. This makes it easier for the driver to realize comfortable driving when the engine 21 is driven in the vehicle 10.

The operation element group 18 includes an accelerator pedal 60 provided on the front side of the driver's seat 14, a brake pedal 63 (FIG. 3A) which is a braking instruction unit, and a steering operator which is a turning instruction unit provided on the front side of the driver's seat 14. It has a 61, a forward / backward lever 62 (FIG. 3A), and an operation panel 52.

The steering operator 61 is composed of a steering wheel fixed to a steering shaft protruding diagonally rearward on the upper side of the front cover 13. The steering operator 61 is connected to the two left and right front wheels 15 so as to be able to steer the front wheels 15 via an Ackermann-type steering mechanism.

As shown in FIG. 3A, the forward / backward lever 62 has four positions: a low-speed forward position (L position), a high-speed forward position (H position), a neutral position (N position), and a reverse position (R position). The operation position can be switched between. The low-speed forward position is a position for selecting a shift stage suitable for low-speed travel, and the high-speed forward position is a position for selecting a shift stage suitable for high-speed travel. The forward / backward lever 62 is supported by the vehicle body so as to be able to swing in the front-rear direction (vertical direction in FIG. 3A). The forward / backward lever 62 may be configured so that the operating position can be switched between the three positions of the forward position, the neutral position, and the reverse position.

As shown in FIG. 1, the engine 21 is fixed to the lower side of the loading platform 19 on the rear side of the driver's seat 14 in the frame 11. The engine 21 is started at an idle speed by turning on a start switch (not shown). As the engine 21, any one of a plurality of types including a gasoline engine and a diesel engine can be used. The power of the engine 21 is transmitted to the two left and right rear wheels 16 via the rear power transmission unit 25, so that the two rear wheels 16 are driven.

The motor 22 is arranged inside the front case 40 (FIG. 2), which will be described later, fixed to the front side of the driver's seat 14 in the frame 11. A battery 23 (FIG. 2) is electrically connected to the motor 22 via an inverter 24a (FIG. 2). The battery 23 may be arranged inside the front cover 13 or below the driver's seat 14 or the loading platform 19. The start switch (not shown) provided on the front side of the driver's seat 14 of the motor 22 is turned on, and the operation panel 52 (FIG. 5A) described later gives an instruction to constantly drive the front wheels 15 and the rear wheels 16. It is started by selecting the always 4WD mode, which represents the always four-wheel drive, or the EV mode.

As the motor 22, various types of motors such as a DC motor, a permanent magnet type motor, and an induction motor can be used. The power of the motor 22 is transmitted to the two left and right front wheels 15 via the front power transmission unit 41, so that the two front wheels 15 are driven. As a result, the motor 22 drives the front wheels 15.

The rear power transmission unit 25 and the front power transmission unit 41 will be described. As shown in FIG. 2, the rear power transmission unit 25 includes a belt-type continuously variable transmission CVT 26, a gear transmission 30, a differential device 36, an output shaft 37, and a rear axle 38. The rear power transmission unit 25 is connected between the engine 21 and the rear wheels 16 so that power can be transmitted from the engine 21 to the rear wheels 16. Therefore, the rear wheels 16 and the engine 21 are connected via the CVT 26.

The CVT 26 is configured by engaging the drive pulley 27 and the driven pulley 28 so that the belt 29 is wound around. The drive pulley 27 is supported by a first fixed sheave 27a connected to the output shaft 21a of the engine 21 via a centrifugal clutch 80 (FIG. 3B) and axially movable to the output shaft 21a, and is supported by the first fixed sheave 27a. It has a first movable sheave 27b that faces the sea. The first fixed sheave 27a is supported only by rotation on the output shaft 21a by a bearing or the like, and does not move in the axial direction.

As shown in FIG. 3B, the centrifugal clutch 80 has an output shaft 21a and a first fixed sheave 27a when the engine speed per minute, which is the rotation speed of the engine 21, is less than the belt gripping speed N1 described later. Block the connection. On the other hand, when the engine speed is belt gripping speed N1 or higher, the centrifugal clutch 80 connects the output shaft 21a and the first fixed sheave 27a via the centrifugal clutch 80. As a result, the power of the output shaft 21a is transmitted to the first fixed sheave 27a. For example, in the centrifugal clutch 80, one end of a rotating shaft provided at one end in the circumferential direction of a plurality of clutch weights 80b is supported by a clutch plate 80a fixed to an output shaft 21a, and the other end of the rotating shaft of each clutch weight 80b is supported. , Supported by the side plate 80c. The plurality of clutch weights 80b are arranged side by side in the circumferential direction between the clutch plate 80a and the side plate 80c, and are urged inward in the radial direction by the spring 80d. A clutch shoe 80e is provided at the other end of the clutch weight 80b in the circumferential direction, and the other end of the clutch weight 80b in the circumferential direction is displaced outward in the radial direction by a centrifugal force generated when the output shaft 21a rotates, so that the clutch shoe 80e becomes the first The output shaft 21a and the first fixed sheave 27a rotate integrally with the inner peripheral surface of the fixed sheave 27a by frictional engagement.

As shown in FIG. 2, the driven pulley 28 is supported by the second fixed sheave fixed to the input shaft 31 of the gear transmission 30 and the input shaft 31 so as to be movable in the axial direction, and faces the second fixed sheave. It has a second movable sheave. The gear transmission 30 corresponds to a wheel-side power transmission unit. The first movable sheave 27b (FIG. 3B) of the drive pulley 27 is moved in the axial direction by the actuator 26a (FIG. 3B) including the motor. The second movable sheave of the driven pulley 28 is elastically urged by a spring (not shown) so as to approach the second fixed sheave. The actuator 26a brings the first movable sheave 27b of the drive pulley 27 closer to the first fixed sheave 27a as the rotation speed of the engine 21 increases. As a result, when the rotation speed of the engine 21 is low, the width between the first movable sheave 27b and the first fixed sheave 27a (width between sheaves) becomes large as shown in FIG. Therefore, the CVT 26 is continuously changed, and the ratio (Na / Nb) of the rotation speed Na of the drive pulley 27 and the rotation speed Nb of the driven pulley 28, which is the reduction ratio of the CVT 26, becomes large. On the contrary, when the rotation speed of the engine 21 is increased, the width between sheaves of the drive pulley 27 is reduced, so that the CVT 26 is continuously variable-shifted and the reduction ratio (Na / Nb) of the CVT 26 is reduced. As a result, the torque of the input shaft 31 during low-speed running can be increased, and fuel efficiency during high-speed running can be improved.

The gear transmission 30 includes a rear case 35 fixed to the rear side of the engine 21 in the frame 11, and an input shaft 31, a transmission shaft 32, and a final shaft 33 rotatably arranged in the rear case 35. There is. The gear transmission 30 enables power to be transmitted from the input shaft 31 to the final shaft 33 via a gear mechanism and slide gears provided around the transmission shaft. The slide gear is connected to the forward / backward lever 62. In response to the operation of the forward / backward lever 62, the slide gear moves in the axial direction, and the engaging gear is switched, so that the relationship between the rotation direction of the input shaft 31 and the rotation direction of the final shaft 33 is switched. The power transmitted to the final shaft 33 is transmitted to the transmission gear 36a of the differential device 36 via the gear mechanism. Two left and right output shafts 37 are differentially connected to the differential device 36. The differential device 36 is arranged inside the rear case 35. A rear wheel 16 is connected to the output shaft 37 via a universal joint and a rear axle 38. As a result, the rear wheels 16 are driven by the engine 21.

When the forward position is selected by the forward / backward lever 62 (FIG. 3A), the vehicle 10 can move forward. When the reverse position is selected by the forward / backward lever 62, the vehicle 10 can move backward. When the neutral position is selected by the forward / backward lever 62, the width between the sheaves of the drive pulley 27 is widened to prevent power transmission between the output shaft 21a of the engine 21 and the belt 29 of the CVT 26.

As shown in FIG. 2, the front power transmission unit 41 includes a gear mechanism 42, a differential device 43, an output shaft 44, and a front axle 45. The front power transmission unit 41 is connected between the motor 22 and the front wheels 15 so that power can be transmitted from the motor 22 to the front wheels 15. The power of the rotating shaft of the motor 22 is transmitted to the transmission gear 43a of the differential device 43 via the gear mechanism 42. Two left and right output shafts 44 are differentially connected to the differential device 43. A front wheel 15 is connected to the output shaft 44 via a universal joint and a front axle 45. The motor 22, the gear mechanism 42, and the differential device 43 are arranged inside the front case 40. The front case 40 is fixed to the front side of the frame 11 (FIG. 1). As a result, the front wheels 15 are driven by the motor 22.

As shown in FIGS. 2 and 3A, the sensor switch group 50 includes a steering sensor 51, a lever sensor 53, a first pedal sensor 54, a second pedal sensor 64, a rear axle speed sensor 55, a front axle speed sensor 56, and an engine. It includes a speed sensor 57.

The steering sensor 51 detects the operating angle of the steering operator 61 and transmits the detection signal to the control device 70 described later. The steering sensor 51 may be omitted.

The lever sensor 53 detects the position of the forward / backward lever 62 and transmits the detection signal to the control device 70 described later. When the control device 70 determines from the detection signal of the lever sensor 53 that the forward / backward lever 62 is in the neutral position, the first movable sheave 27b of the drive pulley 27 is largely separated from the first fixed sheave 27a, and the belt 29 The deflection may be controlled so that the power of the drive pulley 27 is not transmitted to the belt 29.

The first pedal sensor 54 detects the amount of operation of the accelerator pedal 60 as the accelerator opening degree, and transmits the detection signal to the control device 70. The accelerator opening degree corresponds to the accelerator operating amount, and when the maximum depression is made, the fully opened state is set to 100%, and the ratio of the depressed amount to the fully opened state is represented. The control device 70 has an engine control unit 71 (FIG. 4). The engine control unit 71 controls the throttle valve so that the opening degree of the throttle valve (not shown) of the engine 21 increases as the opening degree of the accelerator corresponding to the operation amount of the accelerator pedal 60 increases. A valve drive motor controlled by the engine control unit 71 may be provided to drive the throttle valve. The opening degree of the throttle valve changes according to the drive of the valve drive motor. The rotation speed of the engine 21 is adjusted by the opening degree of the throttle valve, and the larger the opening degree of the throttle valve, the higher the rotation speed of the engine 21. The meaning of "rotation speed" also includes the number of rotations, which is the rotation speed per unit time, for example, per minute.

The drive unit of the throttle valve may be connected to the accelerator pedal 60 via a link or a cable, and the opening degree of the throttle valve may be increased as the amount of operation of the accelerator pedal 60 increases. In this case, the first pedal sensor does not directly detect the pedal position of the accelerator pedal 60, but is provided near the throttle valve to detect the opening degree of the throttle valve, so that the pedal position of the accelerator pedal 60 is indirectly detected. May be detected in.

The brake pedal 63 is connected to a hydraulic pressure generating mechanism (not shown) via a link. Brake discs (not shown) are fixed to one or both of the front wheels 15 and the rear wheels 16, and two brake pads (not shown) inside and outside the vehicle are arranged on both sides of the brake discs. .. The hydraulic pressure generating mechanism applies an hydraulic pressure to one of the two brake pads to generate a braking force that sandwiches the brake disc.

A signal from the operation panel 52 (FIG. 3A) is also input to the control device 70 (FIG. 2). The operation panel 52 is provided, for example, on the driver's seat 14 side of the front cover 13 so as to be operable by the driver, and indicates the drive mode of the vehicle 10 by operation. The operation panel 52 is, for example, a touch panel type display, and includes six display areas having first, second, and third display areas 81, 83, and 85. FIG. 5A is a diagram showing a first display area 81 having a plurality of traveling mode selection units on the operation panel 52. The plurality of travel mode selection units include an EV mode selection unit 82a, an engine travel mode selection unit 82b, a constant 4WD mode selection unit 82c, and an OFF mode selection unit 82d. The "EV mode" is a mode in which the engine 21 is constantly stopped and the vehicle travels using only the motor 22 as a drive source of the vehicle, and a signal indicating an EV mode instruction by touching the EV mode selection unit 82a is a control device 70. Will be sent to. The "engine running mode" is a mode in which the motor 22 is constantly stopped and the vehicle runs using only the engine 21 as a driving source of the vehicle, and a signal indicating an instruction of the engine running mode is sent by touching the engine running mode selection unit 82b. It is transmitted to the control device 70. The "always 4WD mode" is a mode in which both the engine 21 and the motor 22 are used as the drive source of the vehicle to drive the vehicle in four wheels at all times, and a signal indicating the instruction of the 4WD mode at all times by touching the 4WD mode selection unit 82c. Is transmitted to the control device 70. The "OFF mode" is a mode in which one of the EV mode, the engine running mode, and the 4WD mode is not always fixed and selected, and a signal indicating an OFF mode instruction by touching the OFF mode selection unit 82d is a control device. It is transmitted to 70. For example, the OFF mode is selected before selecting any of the support modes shown in FIG. 5B, which will be described later. When any of the support modes is selected, the control device 70 may automatically select the OFF mode.

Further, the vehicle 10 has a drive changeover switch or a drive changeover lever capable of switching between EV mode, engine running mode, constant 4WD mode, and OFF mode, and by the changeover, a signal indicating an instruction of the corresponding mode is sent to the control device 70. It may be sent to.

Further, the control device 70 has a motor control unit 72 (FIG. 4). The motor control unit 72 controls the motor 22 so that the rotational speed of the motor 22 increases as the amount of operation of the accelerator pedal 60 increases while the EV mode or the 4WD mode is always instructed.

Further, when the 4WD mode is always executed, the electric power corresponding to the output generated by the motor 22 may be generated by the generators GE1 and GE2 by driving the engine 21. For example, the total of the generated torque, which is the torque for generating the generators GE1 and GE2, is the torque corresponding to the output of the motor 22, and can be (output of the motor 22) × 60 / (2π × engine rotation speed). As a result, the vehicle can be driven by four-wheel drive while suppressing a decrease in the charge amount of the battery 23.

The rear axle speed sensor 55 detects the rotational speed of the transmission gear 36a (FIG. 2) of the differential device 36. The transmission gear 36a is fixed to the rear differential case of the differential device 36. The rear differential case rotates at the average rotation speed of the two rear axles 38 on the left and right. As a result, the rear axle speed sensor 55 can detect the average rotational speed of the two rear axles 38 on the left and right. The detection signal of the rear axle speed sensor 55 is input to the control device 70 as the rear wheel rotation speed.

The front axle speed sensor 56 detects the rotational speed of the transmission gear 43a (FIG. 2) of the differential device 43. The transmission gear 43a is fixed to the front differential case of the differential device 43. The front differential case rotates at the average rotation speed of the two left and right front axles 45. As a result, the front axle speed sensor 56 can detect the average rotational speed of the two left and right front axles 45. The detection signal of the front axle speed sensor 56 is input to the control device 70 as the front wheel rotation speed. As the vehicle speed detection value described later, the vehicle speed calculated from the average value of the rear wheel rotation speed, the front wheel rotation speed, or both of them can be used.

The engine speed sensor 57 detects the engine speed as the rotation speed of the output shaft 21a of the engine 21 and transmits the detection signal to the control device 70. The control device 70 controls the actuator 26a so as to move the first movable sheave 27b (FIG. 3B) of the drive pulley 27 of the CVT 26 according to the detected value of the engine speed sensor 57.

In the above, the case where the CVT 26 is an electric type including an actuator 26a having a motor has been described, but the CVT is a hydraulic type in which a movable sheave is moved by a hydraulic device, or a machine that moves a movable sheave by a pressing force generating mechanism including a torque cam. It may be an expression.

The control device 70 is called an ECU (Electronic Control Unit), and includes, for example, a microcomputer, a CPU which is an arithmetic processing unit, a storage unit including a memory such as a RAM and a ROM, and an input / output port. The CPU has a function of reading and executing a control program stored in advance in the storage unit. Generally, the function of each means of the control device 70 is realized by executing a control program. The control device 70 includes the engine control unit 71 (FIG. 4) that controls the engine 21 and a motor control unit 72 (FIG. 4) that controls the motor 22.

As shown in FIG. 4, the battery 23 is connected to the motor 22 via the inverter 24a. The inverter 24a converts the direct current output from the battery 23 into alternating current, which is the drive current of the motor 22.

The motor control unit 72 controls the drive of the motor 22 by controlling the inverter 24a in a state where the EV mode or the 4WD mode is always instructed. The forward position of the motor control unit 72 is selected by the forward / backward lever 62 (FIG. 3A) by the detection signal from the lever sensor 53, and the accelerator pedal 60 (FIG. 3A) is operated by the detection signal from the first pedal sensor 54. If it is determined that the motor 22 is present, the motor 22 is controlled to rotate in the direction corresponding to the forward movement. At this time, the drive current is supplied from the battery 23 to the motor 22.

On the other hand, when the motor control unit 72 determines that the neutral position is selected by the forward / backward lever 62, the motor control unit 72 stops the current supply from the battery 23 to the motor 22.

The motor control unit 72 sets the rotation speed of the rear wheels 16 to the front wheels 15 based on the detection signals of the rear axle speed sensor 55 and the front axle speed sensor 56 (FIG. 2) when the EV mode or the constant 4WD mode is instructed. The motor 22 is controlled so as to match the rotation speeds of the motors 22.

Further, the control device 70 controls the actuator 26a so as to change the width between sheaves of the drive pulley 27 of the CVT 26 according to the rotation speed of the engine 21. Further, the centrifugal clutch 80 (FIG. 3B) connected to the CVT 26 cuts off the connection between the output shaft 21a and the drive pulley 27 when the rotation speed of the engine 21 is less than the predetermined speed, and the output shaft 21a and the drive pulley 27 when the rotation speed is equal to or higher than the predetermined speed. Is connected via the centrifugal clutch 80. The predetermined speed is higher than the speed corresponding to the idle speed. As a result, when the accelerator pedal 60 is not depressed and the engine 21 is rotating at an idle speed, the power of the engine 21 is not transmitted to the drive pulley 27.

Further, the control device 70 also has a function of executing any of slow start support, sudden start support, and smooth start support according to the selection of the start support selection unit 84a (FIG. 5B) in the plurality of support selection units described later. Have.

FIG. 5B is a diagram showing a second display area 83 having a plurality of support selection units on the operation panel 52. The plurality of support selection units include a start support selection unit 84a, a regenerative support selection unit 84b, a slip support selection unit 84c, a sudden acceleration support selection unit 84d, and a slope support selection unit 84e. When the start support selection unit 84a is selected by touch, slow start support, sudden start support, and smooth start support, sudden start support, and smoothness based on the operation status of the accelerator pedal 60 (FIG. 3A), the vehicle speed detection value, and the engine speed detection value. Switch the start support. This switching will be described in detail later.

When any of the regenerative support selection unit 84b, the slip support selection unit 84c, the sudden acceleration support selection unit 84d, and the slope support selection unit 84e is selected by touch, a signal indicating the selected support instruction is a control device. It is transmitted to 70. The control device 70 causes the corresponding support to be executed in response to the input of the signal. The vehicle 10 is capable of performing regenerative support, slip support, sudden acceleration support, and slope support when the engine 21 is being driven and traveling.

FIG. 5C is a diagram showing a third display area 85 having a plurality of charging mode selection units on the operation panel 52. The plurality of charge mode selection units include a low power charge mode selection unit 86a, a high power charge mode selection unit 86b, and a charge stop mode selection unit 86c. Both the low power charging mode and the high power charging mode are modes for charging the battery 23. The high power charging mode is a mode in which the charging speed of the battery 23 is higher than that of the low power charging mode. The charge stop mode is a mode for stopping charging of the battery 23. When any of the low power charge mode selection unit 86a, the high power charge mode selection unit 86b, and the charge stop mode selection unit 86c is selected by touch, a signal indicating the selected mode is sent to the control device 70. Will be sent. The vehicle 10 can execute either the low power charging mode or the high power charging mode when the engine 21 is being driven and the vehicle is stopped. More specifically, the vehicle 10 is configured to be switchable between a low power charging mode, a high power charging mode, and a charging stop mode. The method of switching the charging mode will be described later with reference to FIG.

The control at the time of selection of the regeneration support, the slip support, the sudden acceleration support, and the slope support will be described in order with reference to FIGS. 6 to 13. FIG. 6 is a diagram showing a state in which the vehicle 10 shifts from traveling on a flat road 91 to traveling on a downhill 90, and a state in which regenerative support is executed during traveling on a downhill.

When the regenerative support is selected, the control device 70 enters the downhill 90 when the vehicle 10 is driven by the engine 21, and when the accelerator pedal 60 is turned from on to off, that is, when the vehicle is not operated, the vehicle As the braking force of, the engine brake and the braking force due to the regenerative torque of the motor 22 are generated. For example, in the control device 70, a regenerative support selection instruction is input, the forward / backward lever 62 is in a position other than the neutral position, the engine 21 is driven, the accelerator pedal 60 is turned off, the vehicle speed detection value is in a predetermined range, and the brake is applied. The regenerative support may be executed when the regenerative support execution condition in which the pedal 63 is turned off is satisfied. When the regenerative support is executed, the control device 70 controls the inverter 24a connected to the motor 22 so as to generate the regenerative torque. As a result, the vehicle speed can be reduced more quickly than when braking only with the engine brake. Therefore, it becomes easy for the driver to realize comfortable driving.

Further, in addition to the above-mentioned regeneration support execution conditions, the control device 70 executes regeneration support only when the inclination angle θ of the downhill 90 detected by the inclination angle sensor 66 is equal to or greater than a predetermined regeneration support determination inclination angle. It may be configured to be used. As a result, it is possible to prevent sudden deceleration from occurring due to frequent generation of regenerative torque on a downhill with a small inclination angle. For example, as shown in FIG. 6A, when the accelerator pedal 60 is turned on and the vehicle 10 is traveling on a flat road 91 driven by an engine, the regenerative support is not executed because the inclination angle of the road surface is 0. As shown in FIG. 6B, if the accelerator pedal 60 is still on when the vehicle 10 enters the downhill 90 having an inclination angle θ equal to or greater than the regenerative support determination inclination angle, the regenerative support is not executed. .. On the other hand, as shown in FIG. 6C, when the accelerator pedal 60 is turned off and the regenerative support execution condition is satisfied while the vehicle 10 is traveling downhill 90, the regenerative support is executed and the motor 22 executes the regenerative support. Regenerative torque is generated. As a result, the braking force due to the regenerative torque is added to the braking force due to the engine brake, and the vehicle speed can be reduced more quickly.

FIG. 7 is a diagram showing the relationship between the regenerative torque of the motor 22 and the vehicle speed and the inclination angle of the downhill slope in the control when the regenerative support is selected. When the vehicle speed is within a predetermined range, the regenerative torque gradually increases as the vehicle speed increases, and above the predetermined value, the regenerative torque decreases as the vehicle speed increases. Further, the larger the inclination angle of the downhill, the larger the regenerative torque. The control device 70 may calculate the regenerative torque from the relationship shown in FIG. 7 and the vehicle speed detection value and the inclination angle detection value, and control the inverter 24a so as to output the calculated regenerative torque. As a result, it is possible to prevent the driver from being subjected to an impact force at a high deceleration due to the generation of a large regenerative torque when the vehicle speed is high and one or both when the inclination angle is small.

FIG. 8 shows that the vehicle 10 shifts from the normal straight-ahead state to the rear wheel slip state and the rear wheel grip recovery state in the control when the slip support is selected, and the front wheel rotation speed Vf and the rear wheel rotation speed Vr in each state. It is a figure which shows the relationship. When the slip support is selected, when the vehicle 10 drives the engine 21 in the engine running mode or the like and the motor 22 is stopped and running, the rear wheels 16 enter the low friction portion 92 such as muddy and slip. When the rotation speed Vr of the rear wheels 16 exceeds the rotation speed Vf of the front wheels 15, the control device 70 drives the motor 22 and returns the motor 22 from slip to slip-free state by the driving force.

At this time, the forward force can be increased by driving the motor 22 during forward movement, and when the rear wheel 16 escapes from the low friction portion 92 and the rear wheel rotation speed Vr becomes high so as to match the front wheel rotation speed Vf. , The motor 22 is stopped to end the slip support. For example, as shown in FIG. 8A, the front wheel rotation speed Vf and the rear wheel rotation speed Vr coincide with each other when the engine 21 is driven and the motor 22 is stopped to move forward in a normal straight direction. On the other hand, when the rear wheel 16 enters the low friction portion 92 and slips as shown in FIG. 8B, the rear wheel rotation speed Vr exceeds the front wheel rotation speed Vf, so that the motor 22 is driven. Then, when the rear wheel 16 escapes from the low friction portion 92 as shown in FIG. 8C, the grip of the rear wheel 16 is restored and the rear wheel rotation speed Vr matches the front wheel rotation speed Vf, so that the slip support is provided. finish. Even when the slip support is executed in this way, it becomes easy for the driver to realize comfortable driving.

Further, the control device 70 can also generate electric power corresponding to the output generated by the motor 22 by the generators GE1 and GE2 when the slip support is executed. In this case, for example, in the control device 70, a slip support selection instruction is input, the forward / backward lever 62 is in a position other than the neutral position, the engine 21 is driven, the charge amount of the battery 23 is less than a predetermined amount, and the accelerator pedal. Slip when 60 is turned on, the value obtained by subtracting the front wheel rotation speed Vf from the rear wheel rotation speed Vr is equal to or higher than the predetermined value, the brake pedal 63 is turned off, and the slip support execution condition during which the regeneration support is not being executed is satisfied. Perform support. When the slip support is executed, the control device 70 can drive the motor 22 and generate electric power corresponding to the output generated by the motor 22 by the generators GE1 and GE2. For example, the output of the motor 22 is represented by (required motor) × 2π × (motor rotation speed) / 60. At this time, the total of the power generation torque, which is the torque for generating the generators GE1 and GE2, can be obtained by (output of the motor 22) × 60 / (engine rotation speed × 2π). When the vehicle is provided with only one of the generators GE1 and GE2, the generated torque can be obtained by (output of motor 22) × 60 / (engine rotation speed × 2π). As a result, it is possible to suppress a decrease in the charge amount of the battery 23.

FIG. 9 is a diagram showing the relationship between the accelerator opening degree and the engine torque in the control when the slip support is selected. The control device 70 generates engine torque according to the accelerator opening degree when the slip support is executed. At this time, as shown in FIG. 9, the engine torque can be linearly increased according to the increase in the accelerator opening degree.

FIG. 10 is a diagram showing the relationship between the elapsed time and the motor torque in the control when the slip support is selected. As shown in FIG. 10, when the slip support is executed, the control device 70 increases the elapsed time from the start of driving the motor 22 until the motor torque reaches the allowable torque for a short period of time, which is higher than the continuous rated torque. The torque can be increased to maintain ta for a predetermined time. The predetermined time permissible torque is a torque at which the output is permissible from the aspect of motor protection only when the predetermined time is within a short time ta. Then, the control device 70 can then reduce the motor torque to the continuous rated torque and maintain it. This makes it easier to shift to a slip-free state by rapidly increasing the motor torque.

When turning in either direction when the engine is driven forward, the rotation speed Vf of the front wheels 15 becomes higher than the rotation speed Vr of the rear wheels 16 due to the steering of the front wheels 15, so that slip during engine drive In other cases, it is possible to prevent the motor 22 from being unnecessarily driven.

FIG. 11 is a diagram showing the relationship between the accelerator opening degree and the motor torque in the control when the sudden acceleration support is selected. FIG. 12 is a diagram showing the passage of time of the vehicle driving force and the vehicle speed when the accelerator opening degree is constant in the control when the sudden acceleration support is selected. When the sudden acceleration support is selected, when the vehicle 10 is driven by the engine 21, the control device 70 adds the driving force of the motor 22 to the driving force of the engine 21 to accelerate the vehicle. For example, in the control device 70, a sudden acceleration support selection instruction is input, the forward / backward lever 62 is in a position other than the neutral position, the engine 21 is driven, and the charge amount of the battery 23 is equal to or greater than the predetermined sudden acceleration support determination amount. The detected accelerator opening is equal to or greater than the predetermined sudden acceleration support determination opening, the accelerator change speed, which is the time change rate of the accelerator opening, is equal to or greater than the predetermined sudden acceleration support determination speed, the brake pedal 63 is turned off, and the brake pedal 63 is turned off. Sudden acceleration support is not being executed for regeneration support, slip support, or start support. Sudden acceleration support is executed when the execution conditions are met. By executing this sudden acceleration support, the engine 21 is driven, but the speed of the vehicle 10 can be increased more rapidly than when the motor 22 is stopped, so that it becomes easier for the driver to realize comfortable driving. ..

For example, as shown in FIG. 11, the control device 70 rapidly increases the motor torque until the motor rated torque is reached in accordance with the increase in the accelerator opening degree by starting the execution of the sudden acceleration support, and the accelerator opening degree increases. Can also maintain its motor torque. As a result, as shown in FIG. 12A, in the running of the vehicle 10 driven by the engine, the driving of the motor 22 can be started by depressing the accelerator pedal 60 at time t1. As a result, the overall driving force of the vehicle can be increased in addition to the increase in the driving force of the engine 21. Therefore, as shown in FIG. 12B, the vehicle speed can be rapidly increased after the accelerator pedal 60 is depressed. At this time, the relationship between the accelerator opening degree and the engine torque is the same as in FIG. 9, and the engine torque can be increased according to the increase in the accelerator opening degree.

FIG. 13 shows the vehicle position (a) when traveling on the flat road 91, the vehicle position (b) at the start of the slope support, and the vehicle position (c) when the target vehicle speed is reached by executing the slope support. It is a figure. When the slope support is selected, when the vehicle 10 is driven by the engine 21, the control device 70 has a vehicle speed V1a which is the approach speed to the uphill 93 and a vehicle speed Vm which is the passing speed of the uphill 93. Drive the motors 22 so that they are equal. For example, in the control device 70, a slope support selection instruction is input, the forward / backward lever 62 is in a position other than the neutral position, the engine 21 is driven, the charge amount of the battery 23 is equal to or more than a predetermined slope support determination amount, and the vehicle is tilted. When the inclination angle θ detected by the angle sensor 66 is equal to or greater than the predetermined slope support inclination angle, the accelerator pedal 60 is turned on, the brake pedal 63 is turned off, and regeneration support, slip support, sudden acceleration support, or start support is being executed. Slope support is not executed. Slope support is executed when the execution condition is satisfied. For example, as shown in FIG. 13A, when the vehicle 10 is driven by an engine and is traveling on a flat road 91, the slope support is not executed because the inclination angle of the road surface is 0. As shown in FIG. 13B, when the vehicle 10 enters the uphill 93 having an inclination angle θ equal to or greater than the slope support inclination angle, the execution of the slope support is started and the motor 22 is driven. The control device 70 stores the vehicle speed V1a at the start of execution of the slope support in the storage unit. The control device 70 controls the motor 22 with the vehicle speed V1a as the target vehicle speed while the vehicle 10 is traveling uphill 93. For example, the vehicle speed Vm when the vehicle 10 is at the position shown in FIG. 13C is made to match the vehicle speed V1a. As a result, the driver can drive the vehicle while automatically maintaining the same vehicle speed as the approach speed to the uphill 93, which makes it easier for the driver to realize comfortable driving. Therefore, any of the regenerative support, the slip support, the sudden acceleration support, and the slope support described with reference to FIGS. 6 to 13 makes it easier for the driver to realize comfortable driving.

FIG. 14 is a flowchart showing a method of switching the charging mode of the battery 23 in the embodiment. Steps S1 to S8 are executed by the control device 70. In step S1, it is determined whether or not the forward / backward lever 62 is in the neutral position by the detection signal of the lever sensor 53. If step S1 is an affirmative determination (YES), it is determined that the vehicle is stopped, the process proceeds to step S2, and the vehicle stop charging process of steps S2 to S7 is executed. If step S1 is a negative determination (NO), the process proceeds to step S8, and the traveling process is executed. For example, when the condition that only the engine 21 is driven as the drive source is satisfied, the traveling time processing by the engine drive is executed.

On the other hand, in step S2, it is determined whether or not the charging stop mode is selected by touching the operation panel 52. If step S2 is affirmative, the charge stop mode is executed in step S3. In the charge stop mode, for example, the engine is driven by the idle torque at the idle speed as the required engine torque. At this time, the power generation in the generators GE1 and GE2 is stopped, and the charging from the generators GE1 and GE2 to the battery 23 is stopped.

On the other hand, when the negative determination is made in step S2, it is determined in step S4 whether or not the low power charging mode is selected by touching the operation panel 52. If step S4 is affirmative, the low power charging mode is executed in step S5. In the low power charging mode, the engine 21 is driven with, for example, the required engine torque (idle torque + predetermined low power charging torque). The low power charging torque is lower than the high power charging torque described later. Further, the generators GE1 and GE2 are generated with a low power charging torque as the required generator torque. As a result, the generators GE1 and GE2 generate low power charging to the battery 23 at a low charging speed.

If the negative determination is made in step S4, it is determined in step S6 whether or not the high power charging mode is selected by touching the operation panel 52. If step S6 is affirmative, the high power charging mode is executed in step S7. In the high power charging mode, the engine 21 is driven with, for example, the required engine torque (idle torque + predetermined high power charging torque). The high power charging torque is higher than the low power charging torque. Further, the generators GE1 and GE2 are generated with a low power charging torque as the required generator torque. As a result, the power generation of the generators GE1 and GE2 executes high-power charging in which the charging speed of the battery 23 is higher than that in the low-power charging mode. In any of the execution of the charge stop mode, the low power charge mode, and the high power charge mode in steps S3, S5, and S7, the required motor torque of the motor 22 is 0 Nm, and the required motor rotation speed is 0 min ^-1 . On the other hand, when the negative determination is made in step S6, the control of switching the charging mode ends. The control of switching the charging mode also ends when the execution of steps S3, S5, and S7 ends.

Since the charging mode can be switched between the low power charging mode and the high power charging mode as described above, the battery 23 can be switched to an appropriate charging mode. For example, by allowing the user to switch the charging mode, it is possible to select an appropriate charging mode from the viewpoint of efficiency or battery protection according to the stop time of the vehicle.

Next, a control method when starting support is selected will be described. FIG. 15 is a flowchart showing a control method when starting support is selected in the embodiment. Hereinafter, the reference numerals in FIGS. 1 to 5C will be used as appropriate for description. The processing of steps S11 to S16 is executed by the control device 70. In step S11, it is determined by touching on the operation panel 52 whether or not the start support is selected. If the determination in step S11 is affirmative (yes), the process proceeds to step S12. If step S11 is a negative determination (NO), the process of step S11 is repeated.

In step S12, it is determined whether or not the slow start support condition is satisfied. For example, when the vehicle speed detection value is equal to or less than the maximum vehicle speed V1 for slow start, which is a predetermined speed, and the detected accelerator opening is less than the first predetermined value, it is determined that the slow start support condition is satisfied. For example, when the accelerator opening degree is (predetermined slow start maximum opening AO1-α) or less, it is determined that the slow start support condition is satisfied. At this time, α is a predetermined margin amount other than 0, for example. The slow start maximum opening degree AO1 is a first predetermined value. If step S12 is an affirmative determination, "slow start support" is executed in step S13.

If step S12 is a negative determination, it is determined in step S14 whether or not the sudden start support condition is satisfied. For example, when the change speed, which is the time change rate of the detected accelerator opening, is the predetermined sudden start determination change speed VA1 or more, and the detected accelerator opening is (predetermined sudden start determination opening AO2 + α) or more. It is determined that the sudden start support condition is satisfied. The sudden start determination change speed VA1 corresponds to a predetermined time change rate. The sudden start determination opening degree AO2 is a second predetermined value larger than the first predetermined value. If step S14 is an affirmative determination, "sudden start support" is executed in step S15.

If the negative determination is made in step S14, the remaining start support "smooth start support" is executed in step S16. Each of the above starting supports may be executed when the accelerator pedal 60 is continuously depressed.

When the start support is selected on the operation panel 52, the start support may be switched by the processes shown in FIGS. 16 and 17. FIG. 16 is a diagram showing an example of a plurality of switchings between a slow start support, a sudden start support, and a smooth start support when the start support is selected in the embodiment. FIG. 17 is a diagram showing support switching conditions in FIG.

In the examples of FIGS. 16 and 17, the slow start support, the sudden start support, and the smooth start support are switched from the current or previous support when the condition corresponding to the number of the arrow is satisfied. The numbers on the arrows in FIG. 16 correspond to the numbers in the table in FIG. For example, switching from the slow start support to the smooth start support is executed when the detected accelerator opening degree is (low speed maximum opening degree + α) or more, as shown in the column 1 of FIG.

To switch to the slow start support, as shown in columns 2 and 5 of FIG. 17, the vehicle speed detection value is equal to or less than the slow start maximum vehicle speed V1, and the detected accelerator opening is (slow start maximum opening AO1). −α) Executed in the following cases.

To switch to the sudden start support, as shown in columns 3 and 6 of FIG. 17, the detected change speed of the accelerator opening is equal to or higher than the sudden start judgment change speed VA1, and the accelerator opening is (sudden start judgment open). It is executed when the degree is AO2 + α) or higher.

In switching from sudden start support to smooth start support, as shown in column 4 of FIG. 17, the detected accelerator opening is (sudden start determination opening AO2-α) or less, and the vehicle speed detection value is It is executed when the predetermined engine drive start vehicle speed V2 or less and the engine rotation speed detection value is the predetermined belt grip rotation speed N1 or less. The engine drive start vehicle speed V2 is a vehicle speed that switches from traveling driven only by the motor 22 to traveling driven by both the motor 22 and the engine 21 with smooth start support. The belt grip rotation speed N1 is the engine rotation speed when the rotation speed of the engine 21 increases, the centrifugal clutch 80 is connected, and the transmission of the driving force of the engine 21 to the belt 29 of the CVT 26 is started.

A method of executing the slow start support will be described with reference to FIG. FIG. 18 is a diagram showing the relationship between the accelerator opening degree and the motor torque in the slow start support. The slow start support controls the vehicle to be driven only by the motor 22 as a drive source. When the slow start support is executed, the drive of the motor 22 is controlled using the relationship shown in FIG. The slow start support can be executed even when the accelerator opening is 0. The relationship between the torque of the motor 22 and the accelerator opening degree when the slow start support is executed is a relationship in which a predetermined torque T1 is generated when the accelerator opening degree is 0. The torque T1 is maintained when the accelerator opening degree is from 0 to AOA, and the motor torque increases linearly when the accelerator opening degree is from AOA to AOb. At the accelerator opening AOb, the motor torque is torque T2 equivalent to the maximum vehicle speed V1 for slow start in terms of traveling on level ground, and the torque is maintained even if the accelerator opening is further increased. The maximum vehicle speed V1 for slow start can be empirically set to the optimum vehicle speed from, for example, the actual driving of the vehicle. In addition, when the vehicle driving force obtained from the vehicle conditions such as motor torque, wheel radius, reduction ratio, etc., and the running resistance of the vehicle, which fluctuates according to the vehicle speed and the inclination (gradient) of the road surface, match, it is constant. The maximum vehicle speed is obtained. As a result, the torque T2 of the motor 22 for obtaining the maximum vehicle speed V1 for slow start can be calculated from the vehicle speed V1 and the vehicle conditions when traveling on level ground.

Further, in the slow start support, the engine torque becomes the idle torque at the idle speed, and the inverter 24b connected to the generators GE1 and GE2 is controlled so that the generated torque of the generators GE1 and GE2 becomes zero. With the above slow start support, you can start smoothly in the low speed range.

A method of executing the sudden start support will be described with reference to FIGS. 19 and 20. FIG. 19 is a diagram showing the relationship between the accelerator opening degree and the engine torque in the sudden start support. FIG. 20 is a diagram showing the relationship between the accelerator opening degree and the motor torque in the sudden start support. The sudden start support controls the vehicle to be driven by the engine 21 and the motor 22 as drive sources. When the sudden start support is executed, the drive of the engine 21 is controlled using the relationship shown in FIG. When the accelerator opening is 0, the engine 21 generates idle torque at the idle speed. The engine torque increases linearly as the accelerator opening increases.

When the sudden start support is executed, the drive of the motor 22 is controlled using the relationship shown in FIG. The solid line L1 in FIG. 20 shows the motor torque when the sudden start support is executed, and the alternate long and short dash line L2 in FIG. 20 shows the motor torque when the slow start support is executed. The relationship between the torque of the motor 22 and the accelerator opening degree when the sudden start support is executed is a relationship in which a predetermined torque T1 is generated when the accelerator opening degree is 0. As the accelerator opening increases from 0, the motor torque increases linearly until it reaches the motor rated torque, after which the motor torque is maintained at the motor rated torque. When the sudden start support is executed, the degree to which the motor torque increases as the accelerator opening increases until the motor rated torque is reached. When the slow start support is executed, the motor torque increases as the accelerator opening increases. Greater than the degree of torque. As a result, a torque that increases sharply can be obtained even with only the motor 22 as compared with the case of slow start. Further, since the vehicle is driven by adding the torque of the engine 21 to the torque of the motor 22, a sudden start can be realized.

A method of executing the smooth start support will be described with reference to FIGS. 21 to 25. FIG. 21 is a diagram showing motor operation, engine operation, and switching timing to the next stage in smooth start support. FIG. 22 is a diagram showing the passage of time of the vehicle driving force, the vehicle speed, and the engine speed when the accelerator opening degree is constant in the smooth start support. In FIG. 22A, the total driving force of the vehicle is the sum of the driving force of the motor 22 and the driving force of the engine 21.

In the smooth start support, the vehicle 10 is driven only by the motor 22 as a drive source in the initial stage of starting, the vehicle 10 is driven by the engine 21 and the motor 22 as a drive source in the middle stage, and the vehicle 10 is driven only by the engine 21 as a drive source in the latter stage. Is controlled to drive. Smooth start support can be executed, for example, when the accelerator opening is constant. Smooth start support realizes initial drive, medium-term drive, and late-stage drive when the accelerator pedal 60 is continuously depressed, so if the accelerator pedal 60 is turned off during that execution, any of the early, middle, and late stages will be realized. Execution is stopped in that state.

As shown in FIGS. 21 and 22, when the smooth start support is executed, the control device 70 outputs the motor torque according to the detected increase in the accelerator opening at the initial stage of starting when the accelerator pedal 60 is started to be turned on. Let me. FIG. 23 is a diagram showing the relationship between the accelerator opening degree and the motor torque at the initial stage of starting in the smooth starting support. As shown in FIG. 23, the motor torque is maintained at torque T1 when the accelerator opening degree is 0 to AOc, and the motor torque linearly increases as the accelerator opening degree increases when the accelerator opening degree is AOc to AOd. After the accelerator opening AOd, the motor torque is maintained even if the accelerator opening is increased. The vehicle driving force shown in FIG. 22A is realized by the motor torque. At this time, the engine speed in FIG. 22 (c) is an idle speed less than the belt gripping speed N1, and the power of the engine 21 is not transmitted to the belt 29 of the CVT 26. As shown in FIG. 22B, when the vehicle speed reaches the engine drive start vehicle speed V2 due to the increase in the motor torque, the running state is switched to the first stage in the next mid-starting period.

FIG. 24 is a diagram showing the relationship between the elapsed time, the vehicle speed, and the engine torque in the first stage of the mid-starting period in the smooth starting support. In the first stage of the middle stage of starting, the control device 70 increases the engine speed as the accelerator opening increases, as shown in FIG. 22 (c), and increases the elapsed time and vehicle speed as shown in FIG. 24. The corresponding engine torque is output. Specifically, the engine torque increases linearly as the elapsed time from the time of switching to the middle start period increases, and the slope of the straight line increases as the vehicle speed increases. The motor torque in the first stage in the middle stage of starting is the same as in FIG. 24. Then, after the time when the engine speed when the power of the engine 21 is transmitted to the belt 29 of the CVT 26 reaches the belt gripping speed N1, the driving force of the entire vehicle is the driving force of both the engine 21 and the motor 22. It is realized by. Then, as shown in the column of the first stage in the middle stage of starting in FIG. 21, the belt grip determination time (FIG. 22), in which the engine speed is continuously equal to or higher than the belt grip speed N1 for a predetermined time, has elapsed. In that case, the running state is switched to the second stage in the next mid-starting period.

FIG. 25 is a diagram showing the relationship between the accelerator opening degree and the vehicle speed and the motor torque in the second stage of the mid-starting period in the smooth starting support. The control device 70 controls the drive of the motor 22 by using the relationship shown in FIG. 25 in the second stage in the middle stage of starting. Specifically, the motor torque decreases linearly as the vehicle speed increases. Further, a plurality of straight lines representing the relationship between the vehicle speed and the motor torque are set according to the accelerator opening degree, and a straight line in which the motor torque increases as the accelerator opening degree increases is set. On the other hand, the engine 21 outputs the engine torque according to the accelerator opening degree. For example, similar to the engine torque of the sudden start support shown in FIG. 19, the engine torque increases linearly as the accelerator opening degree increases. As a result, as shown in FIG. 22 (a), in the second stage of the middle stage of starting, the driving force of the vehicle by the motor 22 gradually decreases rather than suddenly reaches 0, and the driving force of the vehicle by the motor 22 becomes The driving force of the engine 21 increases in response to the decrease so as to exceed the decrease, whereby the driving force of the vehicle can be increased. Further, when the smooth start support is executed, the control device 70 raises and then lowers the output of the motor 22 according to the passage of time, and sets the output of the engine 21 from the time when the output of the motor 22 is near the maximum value. Increase over time. As a result, as shown by the arrow β in FIG. 22A, the output of the motor 22 can be reduced while smoothly increasing the driving force of the vehicle in the middle stage of starting. Further, in the middle stage of starting, the torque of the motor 22 is reduced after a predetermined belt grip determination time elapses after the engine speed reaches the belt grip speed N1, so that the driving force of the vehicle can be increased more smoothly.

According to the vehicle 10, when the operation amount of the accelerator pedal 60 is not 0 in the vehicle 10 in which the rear wheels 16 are driven by the engine 21 and the front wheels 15 are driven by the motor 22, the operation status of the accelerator pedal 60 is changed. Depending on the situation, either slow start support, sudden start support, or smooth start support is executed. As a result, slow start support is realized when the driver wants a smooth start in the low speed range by operating the accelerator pedal 60, and sudden start support is realized when he wants to reach the high speed range quickly. The vehicle is accelerated by the motor 22 and the engine 21. As a result, it is possible to realize a starting performance close to the driver's intention according to the driving situation, and when a small motor 22 is used, it is possible to prevent an excessive load from being applied to the motor 22 in the high speed range. Durability can be improved. Further, in the execution of the smooth start support, the driving force of the motor 22 can be reduced in the high speed range and accelerated only by the engine 21, so that the energy efficiency can be improved.

Note that the support selection in FIG. 5B is not performed on the operation panel 52, and the support may be selected by one or more switches.

FIG. 26 is a flowchart showing a method of switching the charging mode of the battery 23 in another example of the embodiment. In the configurations of FIGS. 1 to 25, as described with reference to FIG. 14, it has been described that the battery charging mode can be switched by selecting the operation panel 52. On the other hand, in the case of this example, the battery charging mode is automatically switched by the control device 70. Specifically, according to the charge amount of the battery 23 detected by the battery monitoring module 65, when the charge amount is less than the predetermined charge allow amount, the high power charge mode is executed and the charge amount is equal to or more than the predetermined charge allow amount. In the case of, the low power charging mode is executed. The high power charging mode and the low power charging mode are the same as in the case of the configuration described with reference to FIG.

Specifically, the processes of steps S1a to S7a of FIG. 26 are executed by the control device 70. In step S1a, it is determined whether or not the forward / backward lever 62 is in the neutral position by the detection signal of the lever sensor 53. If step S1a is affirmative (YES), the process proceeds to step S2a, and the stop charging process of steps S2a to S6a is executed. If step S1a is a negative determination (NO), the process proceeds to step S7a, and the traveling process is executed.

On the other hand, in step S2a, it is determined whether or not the charge amount of the battery 23 is equal to or more than the predetermined upper limit charge amount. The predetermined upper limit charge amount is a charge amount higher than the predetermined charge allow amount described later, and is set to protect the battery 23 by preventing overcharging of the battery 23. If step S2a is affirmative, the charge stop mode is executed in step S3a. The charge stop mode is the same as in the case of the configuration described with reference to FIG.

If the negative determination is made in step S2a, it is determined in step S4a whether or not the charge amount of the battery 23 is less than the predetermined charge allow amount. When step S4a is affirmative, that is, when the charge amount of the battery 23 is less than the predetermined charge allow amount, there is a large margin until the charge amount reaches full charge, so that the high power charge mode is executed in step S5a. Will be done. When the negative determination is made in step S4a, that is, when the charge amount of the battery 23 is equal to or more than the predetermined charge allow amount, the margin of the charge amount until full charge becomes small, so that the low power charge mode is executed in step S6a. .. When the execution of steps S3a, S5a, and S6a ends, the control of switching the charging mode ends.

In the case of this example as well, as in the configuration of FIGS. 1 to 25, the charging mode can be switched between the low power charging mode and the high power charging mode, so that the battery 23 can be switched to an appropriate charging mode. .. Further, in the case of this example, since the charging mode is automatically switched by the control device 70 according to the charging amount, an appropriate charging mode is executed from the viewpoint of efficiency or battery protection according to the charging amount. In this example, other configurations and operations are the same as those of FIGS. 1 to 25.

In each of the above embodiments, the hybrid vehicle is driven by an engine, and during traveling, one or one of regenerative support, slip support, rapid acceleration support, and slope support. It may be configured so that support for two or any three can be performed.

Further, in each of the above embodiments, the case where the regeneration support, the slip support, the sudden acceleration support, and the slope support are executed when selected on the operation panel 52 has been described. On the other hand, the hybrid vehicle can execute at least two of the regenerative support, the slip support, the sudden acceleration support, and the slope support, and one of the supports is executed according to the traveling condition of the vehicle. May be good.

For example, the hybrid vehicle may be configured to be capable of all of regenerative support, slip support, rapid acceleration support, and slope support. At this time, in the configuration of FIGS. 1 to 25, the control device may execute the regenerative support when the condition excluding the input of the selection instruction of the regenerative support is satisfied from the regenerative support execution conditions. Further, in the configuration of FIGS. 1 to 25, the control device may execute the slip support when the condition excluding the input of the slip support selection instruction from the slip support execution conditions is satisfied. Further, in the configuration of FIGS. 1 to 25, when the condition excluding the input of the sudden acceleration support selection instruction from the sudden acceleration support execution condition is satisfied, the control device executes the sudden acceleration support. You may. Further, in the configuration of FIGS. 1 to 25, the control device may execute the slope support when the condition excluding the input of the slope support selection instruction from the slope support execution condition is satisfied.

FIG. 27 is a side view of another example hybrid vehicle 10a of the embodiment. In the configuration of each of the above examples, the case where the vehicle 10 (FIG. 1) is an off-road type multipurpose vehicle having a loading platform has been described, but in this example, the hybrid vehicle 10a is a working machine (not shown) on the rear side. ) Is a connectable tractor. For example, the hybrid vehicle 10a is an agricultural tractor having a working machine for performing agricultural work. The hybrid vehicle 10a includes front wheels 15 and rear wheels 16a supported on the front and rear of the frame 111, and an engine 21 and a motor 22 supported on the front side of the frame 111. The front wheels 15 are driven by the motor 22, and the rear wheels 16a are driven by the engine 21. The engine 21 is covered with a front cover 13a having a bonnet and a side cover. A work machine can be connected to the rear part of the vehicle, and a PTO shaft 112 for driving the work machine protrudes from the rear end of the case 113 having a power transmission unit for transmitting power from the engine 21. Further, an accelerator pedal 60 is arranged on the front side of the driver's seat 14, and a detection signal of the accelerator opening degree is transmitted from the first pedal sensor 54 (see FIG. 3A) to the control device 70 (see FIG. 3A).

In such a hybrid vehicle 10a as well, the vehicle has slow start support, sudden start support, and smooth start support, as in the configuration of each of the above examples, and the above support is provided according to the operation status of the accelerator pedal 60. Is configured to be executed. In this example, other configurations and operations are the same as those of FIGS. 1 to 25 or 26.

In each of the above examples, the rear wheels 16 and 16a may be driven by the motor, and the front wheels 15 may be driven by the engine. At this time, the first wheel becomes the front wheel 15, and the second wheel becomes the rear wheels 16, 16a.

Further, the acceleration instruction unit is not limited to the accelerator pedal, and the acceleration instruction unit may be configured by, for example, a pair of operation levers oscillating in the front-rear direction on each of the left and right sides of the driver's seat. For example, the right front wheel is driven by the right motor and the left front wheel is driven by the left motor. By tilting the left and right operating levers forward, the front wheels corresponding to the operating levers can be rotated in the forward direction, and by tilting them backward, they can be rotated in the backward direction.

Further, in each of the above examples, the case where either the start support is executed when the start support is selected by the operation panel 52 or the switch has been described, but the operation panel is omitted and the operation status of the acceleration indicator is omitted. Depending on the situation, one of the start support may be executed.

Further, in each of the above examples, the starting support may not be provided.

10,10a hybrid vehicle, 11 frames, 12 platforms, 13,13a front cover, 14 driver's seat, 15 front wheels, 16, 16a rear wheels, 18 operating elements, 19 loading platform, 20 moving body drive unit, 21 engine, 22 motors , 22a rotating shaft, 23 battery, 24a, 24b inverter, 25 rear power transmission unit, 26 CVT, 26a actuator, 27 drive pulley, 28 driven pulley, 29 belt, 30 gear transmission, 31 input shaft, 32 transmission shaft, 33 Final Axle, 35 Rear Case, 36 Differential Device, 37 Output Shaft, 38 Rear Axle, 40 Front Axle, 41 Front Axle, 42 Gear Mechanism, 43 Differential Device, 44 Output Shaft, 45 Front Axle, 50 Sensor Switch Group, 51 Steering sensor, 52 Operation panel, 53 Lever sensor, 54 First pedal sensor, 55 Rear axle speed sensor, 56 Front axle speed sensor, 57 Engine speed sensor, 60 Accelerator pedal, 61 Steering operator, 62 Forward / backward lever , 63 Brake pedal, 64 Second pedal sensor, 65 Battery monitoring module, 66 Tilt angle sensor, 70 Control device, 71 Engine control unit, 72 Motor control unit, 80 Centrifugal clutch, 81 First display area, 82a EV mode selection Unit, 82b engine running mode selection unit, 82c constant 4WD mode selection unit, 82d OFF mode selection unit, 83 second display area, 84a start support selection unit, 84b regeneration support selection unit, 84c slip support selection unit, 84d sudden acceleration Support selection unit, 84e slope support selection unit, 85 third display area, 86a low power charge mode selection unit, 86b high power charge mode selection unit, 86c charge stop mode selection unit, 90 downhill, 91 flat road, 92 low Friction part, 93 uphill, 111 frame, 112 PTO shaft, 113 case.

Claims (14)

The engine that drives the first wheel and
A motor for driving a second wheel separated from the first wheel in the front-rear direction is provided.
Regenerative support that uses the regenerative brake of the motor when decelerating downhill, slip support that returns from slip to a slip-free state by the driving force of the motor when the first wheel slips, and the driving force of the engine. Of the sudden acceleration support that accelerates by applying the driving force of the motor and the slope support that drives the motor so that the approach speed to the uphill and the passing speed of the uphill are equal, at least when the engine is driven. One support is feasible,
Hybrid vehicle. At least two of the regeneration support, the slip support, the sudden acceleration support, and the slope support can be executed, and any one of the supports is executed according to the traveling condition of the vehicle.
The hybrid vehicle according to claim 1. The regeneration support is performed only when the downhill is equal to or greater than a predetermined inclination angle.
The hybrid vehicle according to claim 1 or 2. Equipped with a generator driven by the engine
Execution of the slip support is stopped when the first wheel and the second wheel reach the same speed, and when the slip support is executed, electric power corresponding to the output generated by the motor is generated by the generator.
The hybrid vehicle according to claim 1. A control device for controlling the motor is provided.
When the slip support is executed, the control device increases the torque of the motor as the elapsed time increases from the start of driving the motor until the torque of the motor reaches a predetermined time allowable torque higher than the continuous rated torque. After that, the torque is reduced to the continuous rated torque and maintained.
The hybrid vehicle according to claim 4. The first wheel driven by the engine is the rear wheel, and the second wheel driven by the motor is the front wheel.
The hybrid vehicle according to claim 3 or 5. The generator driven by the engine and
A control device for controlling the motor is provided.
Execution of the slip support is stopped when the first wheel and the second wheel reach the same speed, and when the slip support is executed, electric power corresponding to the output generated by the motor is generated by the generator.
When the slip support is executed, the control device increases the torque of the motor as the elapsed time increases from the start of driving the motor until the torque of the motor reaches a predetermined time allowable torque higher than the continuous rated torque. After that, the torque is reduced to the continuous rated torque and maintained.
The first wheel driven by the engine is the rear wheel, and the second wheel driven by the motor is the front wheel.
The hybrid vehicle according to claim 3. The engine that drives the first wheel and
A motor that is connected to the battery and drives the second wheel that is separated from the first wheel in the front-rear direction.
A generator driven by the engine and charging the battery.
Between the low power charging mode for charging the battery, the high power charging mode for charging the battery and the charging speed for the battery is higher than the low power charging mode, and the charging stop mode for stopping the charging of the battery. Configured to be switchable,
Hybrid vehicle. A charge monitoring unit for detecting the charge amount of the battery is provided.
When the charge amount of the battery is less than the predetermined charge allow amount, the high power charge mode is executed.
When the charge amount of the battery is equal to or more than the predetermined charge allow amount, the low power charge mode is executed.
The hybrid vehicle according to claim 8. The first wheel driven by the engine is the rear wheel, and the second wheel driven by the motor is the front wheel.
The hybrid vehicle according to claim 8. When the four-wheel drive is executed, the electric power corresponding to the output generated by the motor is generated by the generator by driving the engine.
The hybrid vehicle according to claim 10. The first wheel driven by the engine is a rear wheel, and the second wheel driven by the motor is a front wheel.
When the four-wheel drive is executed, the electric power corresponding to the output generated by the motor is generated by the generator by driving the engine.
The hybrid vehicle according to claim 9. An off-road versatile vehicle or tractor that has a loading platform and travels on rough terrain.
The hybrid vehicle according to any one of claims 1 to 12. The engine that drives the first wheel and
It includes a motor that drives a second wheel that is connected to a battery and is separated from the first wheel in the front-rear direction, and a generator that is driven by the engine and charges the battery.
Either a low-power charging mode in which the battery is charged when the engine is driven and the vehicle is stopped, or a high-power charging mode in which the battery is charged and the charging speed of the battery is higher than that of the low-power charging mode. When traveling, the regenerative support that uses the regenerative brake of the motor when decelerating downhill and the driving force of the motor restore the slip to a slip-free state when the first wheel slips. A slip support, a rapid acceleration support that accelerates by adding the driving force of the motor to the driving force of the engine, and a slope that drives the motor so that the approach speed to the uphill and the passing speed of the uphill are substantially equal to each other. Of the support, at least one support is feasible,
Hybrid vehicle.

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