JPH0655941A - Hybrid vehicle - Google Patents

Abstract

PURPOSE:To provide a hybrid type vehicle which can cope with a demand for large braking force without using a resistor to release overcharge or excessive electric power continuing to degradation of a battery when an electric motor or an engine is operated independently. CONSTITUTION:When a motor 15 is operated independently, a braking demand detecting part 30 detects a braking demand. Then, a battery residual quantity detecting part 26 carries out operation on a battery residual quantity from voltage, an electric current, a temperature, specific gravity and so on of a battery 21, and finds motor maximum regenerative torque from vehicle speed and the battery residual quantity by taking into consideration overcharge or rapid charge and so on to the battery 21. When a shift lever position is put in 'R' or 'D' range, regenerative braking is carried out according to a brake stepping-down quantity. On the other hand, when a larger braking demand like '2' or 'L' range is made, the regenerative braking by the motor maximum regenerative torque is carried out, and a clutch 13 is engaged, and braking by an engine brake is used at the same time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hybrid vehicle, and more particularly to a hybrid vehicle having an improved braking method.

[0002]

2. Description of the Related Art In recent years, interest in the environment of the earth has increased, and social demands such as destruction of the natural environment due to air pollution, global warming, and prevention of deterioration of living space due to noise have increased. Along with this, an electric vehicle that drives a vehicle with clean electric power without using an internal combustion engine such as an engine that causes exhaust gas as a drive source is drawing attention. An electric vehicle rotates an electric motor with electric power supplied from a large-capacity battery and uses it as a driving force for the vehicle. Then, the required torque value is calculated from the operation amount such as the accelerator depression amount or the brake depression amount, and the electric current corresponding to the calculated torque value is supplied to the electric motor, so that an appropriate amount according to the driver's request is obtained. Realize running.

However, this electric vehicle requires a battery, and there is a limit to the distance that can be traveled with the amount of electricity charged in this battery. Therefore, a hybrid vehicle that combines a conventional engine that can easily supply fuel and a motor that is clean as energy has also been developed. In this hybrid vehicle, the engine and the motor are connected by a clutch or the like, so that the motor and the engine as a drive source are appropriately switched and used according to various conditions such as a traveling speed and a traveling area ( USP
4,533,011, JP-A-56-132102). For example, when the internal combustion engine runs at low speed where the exhaust gas is large, the motor runs alone, and when running at high speed, both the motor and the engine run or the engine runs alone.

In order to effectively use the braking energy when braking such a hybrid type vehicle, a motor is generally used as a generator and converted into electric energy for regeneration to a battery. However, since the charging capacity of the battery has a certain limit, if a large amount of braking is required while the motor is running alone, regenerating all of that braking energy in the battery will cause overcharging or rapid charging, resulting in battery performance. It was a cause of deterioration. Therefore, conventionally, in such a case, the braking force due to regeneration is limited,
I tried to get most of the braking force by the brakes. In such a case, there is also a hybrid vehicle that uses dynamic braking. That is, a resistor for power consumption is connected to a part of the circuit, and surplus power exceeding the chargeable capacity of the battery is released as heat (Japanese Patent Laid-Open No. 63-2061).
01).

[0005]

However, the braking force generated by the regeneration of the motor is smaller than the braking force of a normal internal combustion engine type vehicle in the entire rotation range, especially on the high rotation side. For this reason, if the regenerative braking force is limited in consideration of the charging capacity of the battery, the braking force is greatly shared by the brakes, which may cause a brake fade phenomenon on a long downhill, for example. . On the other hand, in the case of radiating the surplus power that cannot be regenerated by the resistor, an expensive, heavy-weight and large-volume resistor is required. For this reason, not only the cost of the hybrid vehicle increases, but also the vehicle becomes heavy and heavy, and fuel consumption and power consumption increase as the heavy and heavy vehicles increase.

Therefore, the present invention is a hybrid type capable of responding to a demand for a large braking force without using a resistor for battery deterioration or surplus power discharge while the electric motor or engine is traveling alone. The purpose is to provide a vehicle.

[0007]

According to a first aspect of the present invention, there is provided a hybrid vehicle including an electric motor and an engine, which is driven by at least one driving force.
A battery that supplies electric power to the electric motor, a first braking unit that obtains a braking force by regenerating the battery, a second braking unit that obtains a braking force by engine braking, and a detection unit that detects a required braking force. And a braking control means for simultaneously performing braking by both the first braking means and the second braking means when the detection means detects a braking request of a predetermined amount or more while the electric motor is traveling alone. It is provided in a vehicle to achieve the above object.

[0008]

In the hybrid vehicle of the present invention, the strong braking request signal from the vehicle occupant while the electric motor is traveling alone, for example, the detection means that the vehicle occupant has changed the shift lever position to the "L" range. When detected,
The braking control means uses both regenerative braking and engine braking by engaging an electric motor and an engine with a clutch, for example. As a result, a large braking force can be obtained, a resistor for heat dissipation can be eliminated, and the vehicle can be made lightweight, compact, and low cost.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the hybrid vehicle of the present invention will be described in detail below with reference to FIGS. FIG. 1 shows a basic configuration of a hybrid vehicle. This hybrid vehicle has an engine (E
/ G) 11. Output shaft 1 of this engine 11
2 is connected to the input shaft of the clutch 13. The output shaft 14 of the clutch 13 is fixed to the rotor input side of a motor 15 that functions as an electric motor and a generator.
The clutch 13 is adapted to transmit the rotation of the output shaft 12 to the motor 15 side by engaging and disengaging the output shaft 12.

On the other hand, the rotor output side of the motor 15 is connected to one end of the drive system output shaft 16, and the drive system output shaft 16
The other end of is connected to the differential device 17.
The output of the differential device 17 is transmitted to the drive wheels 19 via the drive shaft 18. Various motors such as an induction motor and a DC motor are used as the motor 15. In this embodiment, a rotor including a 6-pole permanent magnet and an electromagnetic coil including a 3-phase winding, that is, a stator coil are provided. A brushless DC motor is used.

The hybrid vehicle is equipped with a battery 21 which supplies electric power for driving the motor 15.
As the battery 21, a lead acid storage battery, a nickel-cadmium battery, a sodium-sulfur battery, a lithium secondary battery,
Various secondary batteries such as hydrogen secondary batteries and redox type batteries are used. The battery 21 is, for example, 24 times by connecting a plurality of secondary batteries in series or in series / parallel.
It is configured to have a voltage of 0 [V]. The hybrid vehicle includes an engine control unit 22, a clutch drive unit 23, and a motor control unit 24 that control these units. Also, the motion vector detection device is
A battery remaining amount detection unit 26, a vehicle speed sensor 27, an engine rotation sensor 28, an accelerator sensor 29, and a braking request detection unit 30 that detect the state of each unit are provided.

The engine control unit 22 is adapted to perform various adjustments such as throttle valve opening adjustment and fuel injection adjustment according to the required output torque value. The clutch drive unit 23 selectively drives the driving force of the engine 11 and the driving force of the motor 15 according to the traveling mode.
The connection and disconnection of the clutch 13 are controlled so as to output to the clutch 6. The traveling modes include an I-th traveling mode in which the motor 15 alone travels, a II-th traveling mode in which the engine 11 alone travels, and a III-th traveling mode in which the motor 15 and the engine 11 travel together. It is automatically selected according to the opening degree, or is also selected by the driver.

The motor control unit 24 converts the current supplied from the battery 21 into a current value for generating the required torque and supplies the current value to the motor 15, and at the time of regenerative braking, all of the electromotive force generated by the motor 21. Alternatively, the battery 21 is charged by regenerating a part thereof. The battery remaining amount detection unit 26 detects the voltage, current, temperature, specific gravity, etc. of the battery 21, and obtains the battery remaining amount from these data. This battery residual quantity detection section 2
6 includes an analog-digital conversion circuit (not shown), which detects the voltage of the battery 21 and the like, converts each data into a digital value, and outputs the digital value. The vehicle speed sensor 27 detects the vehicle speed from the rotation speed of the output shaft 14, the engine rotation sensor 28 detects the rotation speed of the output shaft 12 of the engine 11, and the accelerator sensor 29 detects the opening degree of the accelerator 31. There is. The braking request detection unit 30 includes a brake sensor 33 that detects the amount of depression of the brake pedal 32, and a shift lever sensor 35 that detects the shift lever position of the shift lever 34.

The hybrid vehicle also includes a control unit 40.
The control unit 40 includes a CPU for performing various controls.
It has a (central processing unit) 41. A ROM (Read Only Memory) 43, a RAM (Random Access Memory) 44, an output I / F (Interface) 4 are provided to the CPU 41 via a bus line 42 such as a data bus.
5 and the input I / F 46 are respectively connected. ROM
43 stores various programs and data for the CPU 41 to determine the traveling state and the like based on various signals input from the input I / F 46 and to appropriately control each unit. The RAM 44 is a working memory for the CPU 41 to perform processing in accordance with the programs and data stored in the ROM 43, and temporarily stores various signals input from the input I / F 46 and control signals output from the output I / F 45. It is supposed to be done.

The output I / F 45 of the control unit 40 has a clutch drive unit 23, an engine control unit 22, and a motor control unit 24.
Are connected to each other, and a control signal is supplied from the CPU 41 in accordance with traveling conditions and the like.
On the other hand, the input I / F 46 has a battery remaining amount detection unit 26,
The vehicle speed sensor 27, the engine rotation sensor 28, the accelerator sensor 29, and the brake sensor 33 are connected, and the CPU 41 reads the respective detection signals and the like.

Next, the braking operation of the hybrid type vehicle thus constructed will be described. The braking operation when the driver issues a braking request while the motor 15 is traveling alone or the engine 11 is traveling alone is peculiar to each embodiment. The braking operation in this case will be described. Outline of Braking Operation When the braking request detection unit 30 detects a braking request while the motor 15 or the engine 11 is traveling alone, the battery remaining amount is calculated from the battery voltage, current, temperature, specific gravity, etc., and the vehicle speed and the battery remaining amount are calculated. The motor maximum regenerative torque T _{bm max} is _calculated . This T _{bm max} is determined in consideration of overcharging or rapid charging of the battery 21. The regenerative braking is performed when the shift lever position is outside the "P" (parking) range and the "N" (neutral) range. That is, when the position of the shift lever 34 is in the "2" (second) range, only regenerative braking according to the brake depression amount is performed. On the other hand, in the case of a larger braking request such as in the "L" range, regenerative braking is performed by the motor maximum regenerative torque, and the clutch 13 is engaged and engine braking is also used.

Details of Braking Operation FIGS. 2 and 3 show the flow of the braking operation by the hybrid vehicle. As shown in this figure, CP
The U41 fetches data such as an accelerator opening degree, a brake depression amount, a shift lever position, a battery remaining amount, and a vehicle speed from each sensor and stores them in the RAM 44 (step 1). Then, the motor maximum regenerative torque T _{bm max} is calculated from the _loaded vehicle speed, remaining battery level, temperature, etc. (step 2). As the maximum motor regeneration torque T _{bm max} , the maximum value that can be regenerated without deteriorating the battery 21 is calculated.

When the motor maximum regenerative torque T _{bm max} is calculated, the shift lever position taken from the shift lever sensor 35 is determined (step 3). When the shift lever position is not in the "P" (parking) range or the "N" (neutral) range (step 3; N), it is determined whether the accelerator opening is larger than the throttle play θf (step 4). When the accelerator opening is larger than θf (step 4; Y), and when it is determined in step 3 that the shift lever position is in the "P" or "N" range (step 3; Y), the process is returned. Let

On the other hand, when the accelerator opening is equal to or less than θf (step 4; N), the CPU 41 determines the shift lever position, and the range other than "2" (second) range or "L" (low) range, that is, "R". If it is in the "," D range (FIG. 3, step 5; N), the regenerative torque T _b corresponding to the depression amount of the brake 32 is calculated (step 6). When the calculated regenerative torque T _b is equal to or less than the motor maximum regenerative torque T _{bm max} calculated in step 2 (step 7; N), the CPU 41 sets the motor regenerative torque T _bm to T _b (step 8). And the CPU 41
Drives and controls the clutch drive unit 23 via the output I / F 45 to release the clutch 13 (step 9).

On the other hand, when the shift lever position is in the "2" range or the "L" range in step 5 (step 5; Y), and in the "R" and "D" ranges, T _b is greater than T _{bm max.} If it is larger (step 7;
Y), the CPU 41 sets the motor regeneration torque T _bm to T _{bm max.}
(Step 10). That is, when the regenerative torque T _b required for the brake depression amount is larger than the motor maximum regenerative torque T _{bm max} , this T
_{If b} is the motor regenerative torque T _bm , the allowable charging range will be exceeded, causing deterioration of the battery 21. Therefore, the maximum motor regenerative torque T _{bm max,} which is the maximum value at which the battery 21 can be charged, is set as the motor regenerative torque T _bm (step 10).

Then, when the shift lever position detected by the shift lever sensor 35 is in the "L" range (step 11; Y), the CPU 41 drives and controls the clutch drive unit 23 through the output I / F 45, and the clutch 13 is engaged (step 12). If the shift lever position is not in the "L" range, that is, in the "R" range,
In the case of "D" range and "2" range, the CPU 41 proceeds to step 9 to release the clutch. After the clutch is released in step 9 or the clutch is engaged in step 12, the CPU 41 commands the motor control unit 24 to output the motor torque via the output I / F 45 (step 13). Further, the CPU 41 causes the engine control unit 22 to fully close the throttle via the output I / F 45,
Output an engine control command such as fuel injection (step 1
4), the process is returned.

As described above, when the shift lever position is in the "D" range with respect to the accelerator opening of 0, regeneration is not performed, and when the shift lever position is in the "2" range, braking is performed only by regeneration.
In the "L" range, regenerative braking and engine braking are performed.

Next, a second embodiment will be described. The structure of the hybrid vehicle according to the second embodiment is
Same as the first embodiment, but different in braking operation. Therefore, the braking operation will be described. Outline of Braking Operation In the second embodiment, in a hybrid type vehicle,
As engine control, the engine brake is controlled by opening and closing the throttle valve while stopping the fuel injection device and igniter. As a result, a smooth combination of engine braking and regeneration is performed while always performing maximum regeneration over the entire vehicle speed range, and a substantially constant braking force can be obtained. That is, the sum of the regenerative torque of the motor 15 and the torque of the engine brake is set as the maximum braking torque. Then, the ratios R (ratio) ₁ , R ₂ , R _o determined by the shift lever position of the shift lever 34.
The braking torque is determined by, and the amount of energy that cannot be recovered by regeneration of the braking torque is absorbed by the engine brake.
The control of the engine brake amount is performed by opening and closing the throttle with the fuel injection device and the igniter stopped. Various maps can be used to determine the braking torque.

Details of Braking Operation FIGS. 4 and 5 show the flow of the braking operation according to the second embodiment. As shown in this figure, the CPU 41
Data such as the accelerator opening, the amount of brake depression, the shift lever position, the remaining battery level, and the vehicle speed are fetched from each sensor and stored in the RAM 44 (step 1). Figure 6
_Represents the relationship between the vehicle speed when the fuel injection is stopped, the motor maximum regenerative torque T _{bm max} , and the maximum engine brake torque T _{be max} . The CPU 41 calculates the motor maximum regenerative torque T _{bm max} and the maximum engine brake torque T _{be max,} which are the maximum values that can be regenerated in the battery 21, from the vehicle speed and the remaining battery amount taken in step 1 according to the relationship shown in this figure. ,decide. Then, a value obtained by adding both the torques T _{bm max} and T _{be max} is set as the total maximum control torque T _{b max} (step 2).

Then, the CPU 41 determines the shift lever position taken from the shift lever sensor (step 3). When the shift lever position is not in the "P" range or the "N" range (step 3; N), it is determined whether the accelerator opening is larger than the throttle play θf (step 4). If the accelerator opening is larger than θf (step 4; Y), and if it is determined in step 3 that the shift lever position is in the "P" range or "N" range (step 3; Y), the processing is executed. To return.

On the other hand, when the accelerator opening is less than θf (step 4; N), the CPU 41 further determines the shift lever position (step 5, step 6, step 7), and depending on each shift lever position. The braking request T _sh by the shift lever is determined (step 8 to step 1).
1). That is, when the shift lever position is "L" range, the step to the maximum control torque T _{b max} of the calculated total by 2 the value obtained by multiplying the R _1/100, a braking request T _sh by the shift lever (Step 8), also , When the shift lever position is in the “2” range, T _{b max} is R ₂ /
The value multiplied by 100 is set as T _sh (step 9).

On the other hand, when the shift lever position is in the "D" (drive) range and the OD (overdrive) switch of the shift lever 34 is off (step 7; N), T _{b max} is R _o / 100. The value multiplied by is T _sh . Also, the shift lever position is "R" (back)
If it is a range (step 5; Y), and "D"
When the OD switch is turned on in the range (step 7; Y), the braking request T _sh by the shift lever is set to 0 (step 11). Where R ₁ is the “L” range and R ₂
Is "2" range, _Ro is "D" when OD switch is OFF
Each braking required value (%) in the range, R ₁ > R
₂ > R _o . Subsequently, the CPU 41 calculates the braking request T _br based on the brake depression amount (step 1
2) The braking demand T _sh by the shift lever is added to this T _br to obtain the regenerative torque T _b (step 13).

In this way, steps 5 to 13 are performed.
In each of the above processes, the braking torque is determined according to the ratios R ₁ , R ₂ , R _o determined by the shift lever position. Then, as described below, the engine brake absorbs energy that cannot be recovered only by regenerating the braking torque.

The CPU 41 compares the regenerative torque T _b determined in step 13 with the motor maximum regenerative torque T _{bm max} calculated in step 2 (step 14) and whether or not the shift lever position is in the "R" range. By (step 15), the motor regeneration torque T _bm and the engine brake torque T _be are determined (steps 16-18). That is, when regenerative torque T _b ≦ motor maximum regenerative torque T _{bm max} (step 14; N), motor regenerative torque T _bm = regenerative torque T _b and engine brake torque T _be = 0 (step 16). And CPU
41 drives and controls the clutch drive unit 23 via the output I / F 45 to release the clutch 13 (step 1
9).

On the other hand, when the regenerative torque T _{b is} greater than the motor maximum regenerative torque T _{bm max} (step 14; Y) and is in the "R" range (step 15; Y), T _bm = T _{bm max} ,
T _be = 0 is set (step 17), the process proceeds to step 19 and the clutch 13 is released. In step 15,
When the range is other than “R” (step 15; N), T _bm =
T _{bm max} , while the engine braking torque T _be is T
_be = T _b −T _bm (T _bmmax ) (step 18).
That is, the amount of energy that cannot be recovered only by the motor regenerative torque T _bm is set as the engine brake torque T _be .

FIG. 7 shows the relationship between the vehicle speed and the engine brake torque T _be depending on the throttle opening. When the engine brake torque T _be is determined in step 18, the CPU 41 calculates the throttle opening that is the determined T _be from the relationship shown in FIG. 7 (step 20). Then, the CPU 41 controls the engine control unit 22 to stop the fuel injection (step 21) and also controls the drive of the throttle to the throttle opening calculated in step 20 (step 22). Then CP
U41 is the clutch drive unit 23 via the output I / F 45.
Is controlled to engage the clutch 13 (step 2
3). After releasing the clutch in step 19 or engaging the clutch in step 23, the CPU 41
The motor regenerative torque T _bm is output as a motor command value to the motor control unit 24 via the output I / F 45 (step 2
4), the process is returned.

Next, a third embodiment will be described. FIG. 8 shows the basic configuration of the third embodiment. In this hybrid vehicle, a transmission is arranged in the route from the engine to the engine drive wheels. That is,
A second speed transmission 20 is arranged between the clutch 13 and the motor 15. The hybrid vehicle includes the transmission actuator 25 connected to the output I / F 45 of the control unit 40, and drives the transmission 20 based on a control signal from the CPU 41 to drive the first speed, the second speed, or the second speed. It is designed to perform speed change control. In this figure, parts other than the transmission 20 and the transmission actuator 25 are similar to those of the first embodiment shown in FIG.

Next, the braking operation according to the third embodiment will be described. Outline of Braking Operation In this embodiment, a braking method is defined as follows for each shift lever position in a hybrid vehicle having a two-stage transmission. In the "D" range and ODon, regenerative braking is not performed. "D" range, ODoff
In case of, only regenerative braking is performed. In case of “2” range,
Use regenerative braking and engine braking in 2nd speed.
In the case of "L" range, regenerative rotation and engine braking at 1st speed (low gear) are used.

Details of Braking Operation FIG. 9 shows the flow of the braking operation according to the third embodiment. Note that the processing starting from step 5 and before this FIG. 9 is the same as the processing shown in FIG. 2, so a description thereof will be omitted. When the accelerator opening is not more than θf (FIG. 2, step 4; N), the CPU 41 determines the shift lever position (FIG. 9, step 5). If the shift lever position is other than the "2" range or the "L" range (step 5; N) and is in the "R" range (step 6; Y), or if the OD switch is in the "D" range in the ON state. In this case (step 7; Y), the regenerative torque T _b corresponding to the depression amount of the brake 32 is calculated (step 8). When the calculated regenerative torque T _b is equal to or more than the motor maximum regenerative torque T _{bm max} calculated in step 2 (FIG. 2) (step 9; N), the CPU 41 sets the motor regenerative torque T _bm to T _b ( Step 10). And C
The PU 41 outputs the clutch drive unit 2 via the output I / F 45.
3 is controlled and the clutch 13 is released (step 1
1).

On the other hand, when the shift lever position is in the "2" range or the "L" range (step 5; Y),
When the OD switch is in the "D" range in the off state (step 7; N), and when the "R" range and the "D" range in which the OD switch is in the on state are T _b > T _{bm max} (step 9; Y), the CPU 41 controls the motor regeneration torque T _{bm
Is the} motor maximum regenerative torque T _{bm max} (step 1
2). When the motor regenerative torque T _bm is determined, the CPU 41
Determines the shift lever position detected by the shift lever sensor 35 (steps 13 and 14). If the shift lever position is in the "R" range, or if it is in the "D" range when the OD switch is on and off (step 1
3; N), the process proceeds to step 11 to release the clutch 13.

On the other hand, if the CPU 41 is in the "L" range (step 14; N), the CPU 41 drives and controls the transmission actuator 25 to set the transmission 20 to the first speed (step 1).
5) If it is in the "2" range (step 14; Y), the transmission 20 is set to the second speed (step 16). Transmission 20
When the setting is made, the CPU 41 drives and controls the clutch drive unit 23 via the output I / F 45 to engage the clutch 13 (step 17). After the clutch is disengaged in step 11 or the clutch is engaged in step 17, the CPU 41 commands the motor controller 24 to output the motor torque via the output I / F 45 (step 18). Further, the CPU 41 outputs a control command to the engine control unit 22 via the output I / F 45 (step 1
9), the process is returned. As the engine command, a command to turn off the fuel injection or a command to cut off the fuel injection above Andring is output.

Next, a fourth embodiment will be described. The basic structure of the hybrid vehicle according to the fourth embodiment is the same as that of the third embodiment. The braking operation is shown in FIG.
As shown in FIG. 0, the throttle control is performed while the fuel injection is stopped, and the basic operation is substantially the same as the braking operation in the second embodiment described with reference to FIGS. Therefore, in FIG. 10, the same operations as those in the second embodiment are designated by the same step numbers, the description thereof will be omitted as appropriate, and the operations unique to this embodiment will be described.

In step 18, of the regenerative torque T _b determined according to the ratios R ₁ , R ₂ and R _o determined by the shift lever position, the motor regenerative torque T
T _bm and T _be are determined so that the engine braking torque T _be absorbs the energy that cannot be recovered only by _bm . Then, the CPU 41 selects the first speed gear or the second speed gear according to the engine brake torque T _be . That is, the CPU 41 calculates from the engine braking torque T _be , and when T _be cannot be covered by the second speed, selects the first speed gear (step 18-2).

Then, the CPU 41 calculates the throttle opening which becomes the determined T _be from the relationship of FIG. 7 (step 20), and after stopping the fuel injection (step 21), drives and controls the transmission actuator 25. The gear of the transmission 20 is set to the selected gear selected in step 18-2 (step 21-2). Thereafter, as in the second embodiment, the operations after step 22 are performed and the process returns.

Next, a fifth embodiment will be described. FIG. 5 shows the structure of a hybrid vehicle in the fifth embodiment. In this embodiment, the output shaft 12 of the engine 11 is connected to the transmission 52 via the torque converter 51 and the clutch C. The output shaft of the transmission 52 is fixed to the rotor input side of the motor 15. The transmission 52 includes a planetary gear unit 53 of a single planetary type, a brake B, and a one-way clutch F. The planetary gear unit 53 is composed of a ring gear R, a pinion P, a carrier CR and a sun gear S.

The output shaft of the clutch C and the carrier C
R is connected, and the rotation of the engine 11 is input to the carrier CR via the torque converter 51 and the clutch C. Then, the rotation of the transmission 52 is output from the ring gear R. A one-way clutch F is connected between the sun gear S and the carrier CR, and a brake B that selectively engages the sun gear S is connected between the sun gear S and the case 54 of the hybrid vehicle.

In the hybrid vehicle thus constructed, the speed is changed by connecting and disconnecting the brake B which is a speed change element. With the function of the one-way clutch F, the brake B is disengaged to stop the engine brake while the clutch C is still engaged, and the brake B is connected to operate the engine brake. That is, according to the fifth embodiment, by shifting the speed with the transmission 52, it is possible to operate and stop the engine brake without disconnecting the clutch C that connects the engine and the vehicle. Therefore, the first and second embodiments are performed.
The braking control can be performed as in the above embodiment.

In the embodiment described above, the coaxial type hybrid vehicle has been described, but the present invention is not limited to this, and as shown in FIG.
5 and the driving force by the engine 11 front and rear drive wheels 1
It is also possible to use a hybrid type vehicle in which front and rear wheels are separated from each other, which is transmitted to 9, 19 ', and to perform the braking operation described in each embodiment.

[0044]

According to the hybrid type vehicle of the present invention, when a strong braking request signal from the vehicle occupant is detected while the electric motor or the engine is traveling alone, for example, the electric motor and the engine are operated by the clutch. By engaging both the regenerative braking and the engine braking by engaging them, a large braking force can be obtained and at the same time, a resistor for heat radiation and the like can be dispensed with, and the weight, compactness and cost of the vehicle can be reduced. it can.

[Brief description of drawings]

FIG. 1 is a basic configuration diagram of a first embodiment of a hybrid vehicle of the present invention.

FIG. 2 is a flowchart showing a part of the braking operation in the first embodiment.

FIG. 3 is a flowchart showing another part of the braking operation in the first embodiment.

FIG. 4 is a flowchart showing a part of the braking operation in the second embodiment.

FIG. 5 is a flowchart showing another part of the braking operation according to the second embodiment.

FIG. 6 is an explanatory diagram showing a relationship between a vehicle speed when fuel injection is stopped, a motor maximum regenerative torque T _{bm max} , and a maximum engine brake torque T _{be max} .

FIG. 7 is an explanatory diagram showing the relationship between the vehicle speed and the engine brake torque T _be depending on the throttle opening.

FIG. 8 is a basic configuration diagram of a hybrid vehicle according to the third embodiment.

FIG. 9 is a flowchart showing a part of the braking operation in the third embodiment.

FIG. 10 is a flowchart showing a part of the braking operation of the fourth embodiment.

FIG. 11 is a basic configuration diagram of a hybrid vehicle according to the fifth embodiment.

FIG. 12 is a basic configuration diagram of a hybrid vehicle according to another embodiment of the invention.

[Explanation of symbols]

 11 engine 13 clutch 15 motor 19 drive wheel 20 transmission 21 battery 22 engine control unit 23 clutch drive unit 24 motor control unit 25 transmission actuator 26 battery remaining amount detection unit 27 vehicle speed sensor 28 engine rotation sensor 29 accelerator sensor 30 braking request detection Part 31 Accelerator 32 Brake 33 Brake sensor 34 Shift lever 35 Shift lever sensor 40 Control part 41 CPU 43 ROM 44 RAM 45 Output interface 46 Input interface

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Hideki Hisada 2-19-12 Sotokanda, Chiyoda-ku, Tokyo Equus Research Co., Ltd.

Claims (1)

[Claims] 1. A hybrid vehicle including an electric motor and an engine, which is driven by at least one driving force, wherein a battery supplies electric power to the electric motor, and a braking force is obtained by regeneration of the battery. 1 braking means, second braking means for obtaining braking force by engine braking, detection means for detecting required braking force, and detection of a braking request of a predetermined amount or more by the detection means while the electric motor is traveling alone The first braking means and the second braking means
A hybrid vehicle, comprising: a braking control unit that uses braking by both of the braking units.