JP2022175744A - vehicle - Google Patents

Abstract

To provide a vehicle which can prevent a shift shock from occurring in the upshift of a gear shift of a transmission.SOLUTION: A transmission is controlled such that a gear shift gets to a target gear shift based on an accelerator operation quantity and a vehicle speed. A clutch is brought into a completely-engaged state when a target gear shift rotation number as the rotation number of an input shaft of the transmission corresponding to the target gear shift, and is brought into a slip engagement state when the target gear shift rotation number is less than the predetermined rotation number. In such a case, when the target gear shift rotation number is the predetermined rotation number or more, and when it is estimated that the upshift of the gear shift is performed within a predetermined time and the rotation number of the input shaft gets to less than the predetermined rotation number after the upshift, the clutch is brought into the slip engagement state.SELECTED DRAWING: Figure 3

Description

The present invention relates to vehicles.

Conventionally, a vehicle of this type has been proposed that includes an engine or motor as a drive source and a clutch provided between the drive source and the drive wheels (see, for example, Patent Document 1). In this vehicle, there is a transition between a first mode in which the drive source is controlled in rotational speed and the clutch is slip-engaged, and a second mode in which the drive source is torque-controlled and the clutch is fully engaged. , a value obtained by subtracting the torque related to the inertia component on the drive source side from the target drive torque set based on the accelerator opening is set as the transmission torque capacity of the clutch in the slip engagement state.

WO2012/053576

In such a vehicle, when the target gear rotation speed, which is the rotation speed of the input shaft of the transmission corresponding to the target gear speed of the transmission, is equal to or higher than a predetermined rotation speed, the clutch is fully engaged and the target gear rotation speed is reached. is less than a predetermined number of revolutions, the clutch is put into a slipping engagement state. In this case, when the clutch is in a fully engaged state, the upshift of the gear stage of the transmission is started, and the rotation speed of the input shaft of the transmission at the gear stage after the upshift becomes less than the predetermined rotation speed. Additionally, the clutch may be re-engaged during an upshift. Switching the clutch from a fully engaged state to a slip engaged state during an upshift may cause a shift shock.

A main object of the vehicle of the present invention is to suppress the occurrence of a shift shock upon upshifting of a gear stage of a transmission.

The vehicle of the present invention employs the following means in order to achieve the above main object.

The vehicle of the present invention is
engine and
a transmission connected to the drive wheels;
a clutch provided between the engine and the transmission;
The transmission is controlled so that the gear stage becomes a target gear stage based on the accelerator operation amount and the vehicle speed, and the clutch is controlled to be the target rotation speed of the input shaft of the transmission corresponding to the target gear stage. a control device that establishes a fully engaged state when the gear rotation speed is equal to or higher than a predetermined rotation speed, and engages a slip engagement state when the target gear rotation speed is less than the predetermined rotation speed;
A vehicle comprising
The control device predicts that an upshift of the gear stage will be performed within a predetermined time when the target gear stage rotation speed is equal to or higher than the predetermined rotation number, and the rotation number of the input shaft after the upshift is set to the above-described value. when it is predicted that the number of rotations will be less than a predetermined number, the clutch is put into a slip engagement state;
This is the gist of it.

In the vehicle of the present invention, the transmission is controlled so that the gear is the target gear based on the accelerator operation amount and the vehicle speed, and the clutch is controlled at the rotational speed of the input shaft of the transmission corresponding to the target gear. When a certain target shift speed rotation speed is equal to or higher than a predetermined speed, the complete engagement state is established, and when the target shift speed rotation speed is less than the predetermined rotation speed, the slip engagement state is established. In this case, when the target gear rotation speed is equal to or higher than the predetermined rotation speed, it is predicted that the gear upshift will be performed within a predetermined time, and that the rotation speed of the input shaft will be less than the predetermined rotation speed after the upshift. When the clutch is engaged, the clutch is brought into a slip engagement state. As a result, before the transmission upshifts, the clutch is switched from the slip engagement state to the fully engaged state when the target gear speed rotation speed rises from less than the predetermined rotation speed to the predetermined rotation speed or more, and then the clutch is switched from the slip engagement state to the full engagement state in a short time. It is possible to suppress the phenomenon that the clutch is switched to the slip engagement state again when the target gear rotation speed becomes less than the predetermined rotation speed due to the change to the upshift side of the gear. That is, it is possible to suppress switching of the clutch from the fully engaged state to the slip engaged state during upshifting of the gear stage. As a result, it is possible to suppress the occurrence of a gear shift shock when the gear is upshifted. In addition, it is possible to suppress switching of the clutch among the slip engagement state, the complete engagement state, and the slip engagement state in a short period of time. Here, the predetermined number of revolutions is set, for example, as the lower limit of the number of revolutions assumed not to cause an engine stall when the clutch is fully engaged. or a slightly lower number of revolutions may be used.

In the vehicle according to the present invention, the control device sets the target shift stage based on a shift line that is a relationship between the accelerator operation amount and the vehicle speed, and furthermore, the control device sets the current speed at the current accelerator operation amount. Whether or not the upshift of the gear position is to be performed within the predetermined time may be predicted based on the vehicle speed difference between the vehicle speed and the vehicle speed of the shift line for the upshift. In this case, the control device may predict, based on the vehicle speed difference and the acceleration of the vehicle, whether or not the upshift of the gear stage will be performed within the predetermined time. By doing so, it is possible to more appropriately predict whether or not the upshift of the gear stage will be performed within the predetermined time.

In the vehicle of the present invention, when the clutch is in the slipping engagement state, the control device selects one of the predetermined number of revolutions and a number of revolutions higher than the number of revolutions of the input shaft by a second predetermined number of revolutions. The engine may be controlled such that the engine rotates at the higher number of revolutions. In this way, when the clutch is in the slipping engagement state, it is possible to further suppress the number of engine revolutions from becoming less than the predetermined number of revolutions.

1 is a configuration diagram showing an outline of the configuration of a hybrid vehicle 20 as an embodiment of the invention; FIG. It is explanatory drawing which shows an example of a shift map. 4 is a flowchart showing an example of a clutch control routine executed by HVECU 70; 4 is a flowchart showing an example of an upshift prediction routine executed by HVECU 70; Target gear stage Gs* and gear stage Gs of the transmission 40 of the embodiment, an upshift prediction flag F1, a low rotation prediction flag F2, a command to the clutch 34, the rotation speed Ne of the engine 22, the rotation speed Ni of the input shaft 41, the target FIG. 4 is a time chart showing an example of a state of a shift speed Nitg; FIG. Time showing an example of the state of the target gear stage Gs*, the gear stage Gs, the command to the clutch 34, the rotation speed Ne of the engine 22, the rotation speed Ni of the input shaft 41, and the target gear rotation speed Nitg of the transmission 40 of the comparative example. Chart.

Next, a mode for carrying out the present invention will be described using examples.

FIG. 1 is a configuration diagram showing the outline of the configuration of a hybrid vehicle 20 as one embodiment of the present invention. As illustrated, the hybrid vehicle 20 of the embodiment includes an engine 22, a clutch 28, a motor 30, an inverter 32, a clutch 34, a transmission 40, a high voltage battery 60, a low voltage battery 62, A DC/DC converter 64 and a hybrid electronic control unit (hereinafter referred to as “HVECU”) 70 are provided.

The engine 22 is configured as an internal combustion engine that outputs power using fuel such as gasoline or light oil from a fuel tank. A crankshaft 23 of this engine 22 is connected to a rotor of a motor 30 via a clutch 28 . The operation of the engine 22 is controlled by an engine electronic control unit (hereinafter referred to as “engine ECU”) 24 .

The engine ECU 24 includes a microcomputer having a CPU, ROM, RAM, flash memory, input/output ports, and communication ports (not shown). The engine ECU 24 receives signals from various sensors necessary for controlling the operation of the engine 22, such as the crank angle θcr from a crank position sensor 23a for detecting the rotational position of the crankshaft 23 of the engine 22, via an input port. is entered. Various control signals for controlling the operation of the engine 22 are output from the engine ECU 24 through an output port. The engine ECU 24 is connected to the HVECU 70 via a communication port. The engine ECU 24 calculates the rotational speed Ne of the engine 22 based on the crank angle θcr of the crankshaft 23 from the crank position sensor 23a.

The clutch 28 is configured, for example, as a hydraulically driven friction clutch, and connects and disconnects the crankshaft 23 of the engine 22 and the rotary shaft of the motor 30 . The motor 30 is configured as, for example, a synchronous generator motor. The rotor of the motor 30 is connected to the crankshaft 23 of the engine 22 via the clutch 28 and to the input shaft 41 of the transmission 40 via the clutch 34 . The inverter 32 is used to drive the motor 30 and is connected to the high voltage power line 61 . Motor 30 is rotationally driven by HVECU 70 controlling switching of a plurality of switching elements of inverter 32 . The clutch 34 is configured, for example, as a hydraulically driven friction clutch, and connects and disconnects the rotating shaft of the motor 30 and the input shaft 41 of the transmission 40 .

The transmission 40 is configured as a four-speed automatic transmission, for example, and has an input shaft 41, an output shaft 42, a plurality of planetary gears, and a plurality of hydraulically driven friction engagement elements (clutches and brakes). The input shaft 41 is connected to the rotor of the motor 30 via the clutch 34 , and the output shaft is connected to the drive shaft 46 which is connected to the drive wheels 49 via the differential gear 48 . Each of the plurality of frictional engagement elements has a hydraulic servo including a piston, a plurality of frictional engagement plates (friction plates and separator plates), an oil chamber to which hydraulic oil is supplied, and the like. Transmission 40 transmits power between input shaft 41 and output shaft 42 by forming first to fourth forward gears and reverse gears by engaging and disengaging a plurality of friction engagement elements. The plurality of friction engagement elements of the clutch 28, the clutch 34, and the transmission 40 described above are operated by supplying and discharging hydraulic oil from a hydraulic control device (not shown).

The high-voltage battery 60 is configured as, for example, a lithium-ion secondary battery or a nickel-hydrogen secondary battery, and is connected to the high-voltage side power line 61 together with the inverter 32 . The low-voltage battery 62 is configured as, for example, a lead-acid battery with a lower rated voltage than the high-voltage battery 60 and is connected to the low-voltage side power line 63 . High voltage battery 60 and low voltage battery 62 are housed in the same case. DC/DC converter 64 is connected to high-voltage power line 61 and low-voltage power line 63 . The DC/DC converter 64 is controlled by the HVECU 70 to supply the power of the high-voltage power line 61 to the low-voltage power line 63 with a stepped-down voltage.

The HVECU 70 includes a microcomputer having a CPU, ROM, RAM, flash memory, input/output ports, and communication ports (not shown). Signals from various sensors are input to the HVECU 70 through input ports. Signals input to the HVECU 70 include, for example, the rotational position θm of the rotor of the motor 30 from a rotational position sensor (for example, a resolver) 30a that detects the rotational position of the rotor of the motor 30, and the position of the input shaft 41 of the transmission 40. The rotation speed Ni of the input shaft 41 from the rotation speed sensor 41a that detects the rotation speed, and the rotation speed No of the output shaft 42 from the rotation speed sensor 42a that detects the rotation speed of the output shaft 42 of the transmission 40 can be mentioned. . The voltage Vb1 of the high voltage battery 60 from the voltage sensor attached between the terminals of the high voltage battery 60, the current Ib1 of the high voltage battery 60 from the current sensor attached to the output terminal of the high voltage battery 60, and the low voltage battery The voltage Vb2 of the low voltage battery 62 from the voltage sensor 67a attached between the terminals of the low voltage battery 62 and the current Ib2 of the low voltage battery 62 from the current sensor attached to the output terminals of the low voltage battery 62 can also be mentioned. A start signal from the start switch 80 and a shift position SP from a shift position sensor 82 that detects the operating position of the shift lever 81 can also be used. Accelerator opening Acc from accelerator pedal position sensor 84 that detects the amount of depression of accelerator pedal 83, brake pedal position BP from brake pedal position sensor 86 that detects the amount of depression of brake pedal 85, vehicle speed V from vehicle speed sensor 88, Vehicle acceleration α from acceleration sensor 89 can also be mentioned.

Various control signals are output from the HVECU 70 through an output port. Signals output from the HVECU 70 include, for example, a control signal to the clutch 28, a control signal to the inverter 32, a control signal to the clutch 34, a control signal to the transmission 40, and a control signal to the DC/DC converter 64. can be mentioned. The HVECU 70 is connected to the engine ECU 24 via a communication port. The HVECU 70 calculates the rotational speed Nm of the motor 30 based on the rotational position θm of the rotor of the motor 30 from the rotational position sensor 30a, and calculates the rotational speed Nm of the frictional engagement elements based on the engaged frictional engagement elements among the plurality of frictional engagement elements. , the shift stage Gs of the transmission 40 is calculated.

The hybrid vehicle 20 of the embodiment thus configured runs in a hybrid running (HV running) mode or an electric running (EV running) mode. The HV driving mode is a mode in which the clutch 28 and the clutch 34 are engaged and the engine 22 is operated while driving. The EV driving mode is the clutch 28 released and the clutch 34 engaged. This is a mode in which the vehicle travels without the engine 22 being operated. The engaged state of the clutches 28, 34 includes not only the fully engaged state but also the slip engaged state.

In the HV travel mode, the following HV travel control is performed by cooperative control of HVECU 70 and engine ECU 24 . In the control of the transmission 40 in the HV running control, the target gear stage Gs* of the transmission 40 is set based on the accelerator opening Acc, the vehicle speed V, and the shift map, and the gear stage Gs and the target gear stage Gs* are set. When they match, the gear stage Gs is held, and when the gear stage Gs and the target gear stage Gs* are different, gear shift processing (upshift or downshift) is performed so that the gear stage Gs matches the target gear stage Gs*. . FIG. 2 is an explanatory diagram showing an example of a shift map. In the figure, solid lines are shift lines for upshifting, and dashed lines are shift lines for downshifting.

Shift processing (upshift and downshift) is performed as follows. First, among the plurality of frictional engagement elements, the hydraulic pressure of the disengagement side element that switches from the engaged state to the disengaged state is lowered by one step, and the stroke control of the engagement side element that is switched from the disengaged state to the engaged state is performed. In stroke control, fast fill to close the gap between the piston of the engagement side element and the friction engagement plate (stroke the piston) and low pressure standby to maintain the hydraulic pressure of the engagement side element at a relatively low standby pressure are performed. . Subsequently, the hydraulic pressure of the disengagement side element is gradually decreased and the hydraulic pressure of the engagement side element is gradually increased to change torque transmission from the disengagement side element to the engagement side element (torque phase). Then, the hydraulic pressure of the disengagement side element is gradually decreased and the hydraulic pressure of the engagement side element is gradually increased, so that the rotational speed Ni of the input shaft 41 of the transmission 40 is adjusted to the rotational speed corresponding to the changed gear stage Gs. change (inertia phase). When the rotation speed Ni of the input shaft 41 reaches the rotation speed corresponding to the changed gear stage Gs, the oil pressure of the engagement side element is further increased to complete the shift process.

In the control of the engine 22 and the motor 30 in the HV running control, the required torque Tin* of the input shaft 41 of the transmission 40 is set based on the accelerator opening Acc, the vehicle speed V, and the gear stage Gs of the transmission 40, and the required torque Tin* is set. Operation control of the engine 22 (intake air amount control, fuel injection control, ignition control, etc.) and motor 30 control (switching control of a plurality of switching elements of the inverter 32) are performed so that Tin* is output to the input shaft 41. .

In the EV travel mode, the following EV travel control is performed by cooperative control of HVECU 70 and engine ECU 24 . The control of transmission 40 in the EV travel control is similar to the control of transmission 40 in the HV travel mode. In the control of the motor 30 in the EV travel control, the required torque Tin* of the input shaft 41 is set as in the HV travel mode, and the motor 30 is controlled so that the required torque Tin* is output to the input shaft 41 .

Next, the operation of the hybrid vehicle 20 of the embodiment configured as described above, particularly the control of the clutch 34 will be described. FIG. 3 is a flow chart showing an example of a clutch control routine executed by the HVECU 70. As shown in FIG. This routine is executed repeatedly.

When the HV driving mode clutch control routine of FIG. 3 is executed, the HVECU 70 first inputs the driving mode Md (step S100). Here, as the driving mode Md, the current driving mode (HV driving mode or EV driving mode) is input. Subsequently, it is determined whether the driving mode Md is the HV driving mode or the EV driving mode (step S110). (step S160), and the routine ends. This full engagement command causes clutch 34 to be fully engaged or held in full engagement.

When the driving mode Md is the HV driving mode in step S110, the target shift stage rotation speed Nitg which is the rotation speed of the input shaft 41 corresponding to the target shift stage Gs* of the transmission 40, the upshift prediction flag F1, the low rotation speed A prediction flag F2 is input (step S120). Here, the target gear stage rotation speed Nitg is a value obtained as a product of the rotation speed No of the output shaft 42 of the transmission 40 detected by the rotation speed sensor 42a and the gear ratio ρ at the target gear stage Gs*. is entered. Note that the target gear speed Nitg is the input shaft speed detected by the speed sensor 41a when the gear Gs of the transmission 40 and the target gear Gs* match (when the speed change process is not being performed). 41 rotation speed Ni.

The upshift prediction flag F1 is a flag indicating a prediction result as to whether or not an upshift of the gear stage of the transmission 40 will be performed within a predetermined time T1 (for example, about several seconds to 10 seconds). The value set by the routine is entered. The low speed prediction flag F2 is a flag indicating a prediction result as to whether or not the rotation speed Ni of the input shaft 41 will become less than the predetermined rotation speed Ni1 after the gear position of the transmission 40 is upshifted. The value set by the routine is entered. The predetermined rotation speed Ni1 causes an engine stall when the clutch 34 is fully engaged in the HV driving mode (when the rotation speed of the engine 22 and the rotation speed of the input shaft 41 of the transmission 40 are made the same). It is set as the lower limit of the rotation speed range in which it is assumed that it will not occur, and for example, the same rotation speed as the idle rotation speed Nidl of the engine 22 or a rotation speed slightly lower than that is used. Hereinafter, the description of the clutch control routine of FIG. 3 will be suspended, and the upshift prediction routine of FIG. 4 will be described. This routine is repeatedly executed when the running mode Md is the HV running mode.

When the upshift prediction routine of FIG. 4 is executed, the HVECU 70 first inputs data such as accelerator opening Acc, vehicle speed V, and vehicle acceleration α (step S200). Here, a value detected by the accelerator pedal position sensor 84 is input as the accelerator opening Acc. A value detected by the vehicle speed sensor 88 is input as the vehicle speed V. FIG. A value detected by the acceleration sensor 89 is input as the vehicle acceleration α.

When the data is input in this manner, the upshift vehicle speed Vup, which is the vehicle speed of the upshift line of the transmission 40 at the current accelerator opening Acc, is set (step S210). This processing can be performed by applying the current accelerator opening Acc to the shift map of FIG. For example, when the current gear stage Gs is 1st gear, the vehicle speed V at the intersection of the current accelerator opening Acc and the upshift line from 1st gear to 2nd gear in the gear shift diagram of FIG. 2 is set as the upshift vehicle speed Vup. .

Subsequently, the vehicle speed difference ΔV between the upshift vehicle speed Vup and the current vehicle speed V is calculated (step S220), and based on the vehicle speed difference ΔV and the vehicle acceleration α, the upshift of the gear stage of the transmission 40 is performed for a predetermined time T1. It is predicted whether or not to perform in the future (steps S230, S232). This processing is performed, for example, as follows. When the vehicle acceleration α is equal to or less than 0, it is predicted that the gear position of the transmission 40 will not be upshifted within the predetermined time T1. When the vehicle acceleration α is greater than 0, the vehicle speed difference ΔV is divided by the vehicle acceleration α to calculate the required arrival time Trq until the vehicle speed V reaches the upshift vehicle speed Vup, and the required arrival time Trq is a predetermined time. When it is equal to or less than T1, it is predicted that an upshift of the gear stage of the transmission 40 will be performed within the predetermined time T1. Predict that it will not be performed within time T1.

When it is predicted in steps S230 and S232 that the gear position of transmission 40 will not be upshifted within predetermined time T1, upshift prediction flag F1 is set to a value of 0 (step S240). At this time, for the sake of convenience, the rotation speed Ni of the input shaft 41 does not become less than the predetermined rotation speed Ni1 after the upshift of the gear stage of the transmission 40 (the engine stall does not occur when the clutch 34 is fully engaged). , the low rotation prediction flag F2 is set to 0 (step S280), and the routine ends.

When it is predicted in steps S230 and S232 that the gear position of transmission 40 will be upshifted within predetermined time T1, upshift prediction flag F1 is set to a value of 1 (step S250), and upshift vehicle speed Vup and vehicle acceleration α are set. , the post-upshift input rotation speed Niupf, which is the rotation speed of the input shaft 41 when the upshift of the gear position of the transmission 40 is completed, is predicted (step S260). Here, the process of step S260 is performed, for example, as follows. First, based on the upshift vehicle speed Vup, the vehicle acceleration α, and the time required for the upshift, the post-upshift vehicle speed Vupf, which is the vehicle speed when the upshift of the gear stage is completed, is predicted. Subsequently, the post-upshift vehicle speed Vupf is multiplied by the conversion coefficient kv to predict the post-upshift output rotation speed Noupf, which is the rotation speed of the output shaft 42 when the upshift of the gear stage is completed. Then, the product of the post-upshift output rotation speed Noupf and the gear ratio ρ in the gear position after the upshift is estimated as the post-upshift input rotation speed Niupf. As the time required for upshifting, a time determined in advance by experiment or analysis is used.

After the post-upshift input rotation speed Niupf is thus predicted, the predicted post-upshift input rotation speed Niupf is compared with the predetermined rotation speed Ni1 (step S270). This processing determines whether or not the rotation speed Ni of the input shaft 41 after the upshift of the gear stage of the transmission 40 is less than the predetermined rotation speed Ni1 (engine stall may occur if the clutch 34 is fully engaged). It is a process of prediction.

When the post-upshift input rotation speed Niupf is equal to or greater than the predetermined rotation speed Ni1 in step S270, the rotation speed Ni of the input shaft 41 does not become less than the predetermined rotation speed Ni1 after the gear stage of the transmission 40 is upshifted (the clutch 34 is fully engaged). engine stall will not occur when the engine is engaged), the low speed prediction flag F2 is set to 0 (step S280), and the routine ends.

When the post-upshift input rotation speed Niupf is less than the predetermined rotation speed Ni1 in step S270, the rotation speed Ni of the input shaft 41 becomes less than the predetermined rotation speed Ni1 after the upshift of the transmission 40 (the clutch 34 is fully engaged). If the engine is engaged, the engine may stall), the low speed prediction flag F2 is set to 1 (step S290), and the routine ends.

The upshift prediction routine of FIG. 4 has been described. Returning to the description of the clutch control routine in FIG. When the target shift speed Nitg, the upshift prediction flag F1, and the low speed prediction flag F2 are input in step S120, the target shift speed Nitg is compared with the predetermined speed Ni1 (step S130). This process is a process for determining whether an engine stall can occur when the clutch 34 is fully engaged.

When the target shift speed Nitg is less than the predetermined speed Ni1 in step S130, it is determined that the engine stall may occur if the clutch 34 is fully engaged, and a slip engagement command is output to the clutch 34 ( Step S170), the routine ends. This slip engagement command causes the clutch 34 to enter or be held in slip engagement. As a result, it is possible to prevent the rotation speed Ne of the engine 22 from becoming less than the predetermined rotation speed Ni1, thereby suppressing the occurrence of engine stall. In the embodiment, as the control of the engine 22 and the motor 30 at this time, the predetermined rotation speed Ni1, the rotation speed (Ni+ΔNi) higher than the rotation speed Ni of the input shaft 41 of the transmission 40 by the predetermined rotation speed ΔNi, The operation of the engine 22 and the motor 30 are controlled so that the required torque Tin* is output to the input shaft 41 while the engine 22 rotates at the larger number of revolutions. Such control can further suppress the rotation speed Ne of the engine 22 from becoming less than the predetermined rotation speed Ni1, thereby further suppressing the occurrence of engine stall.

When the target shift speed Nitg is equal to or higher than the predetermined speed Ni1 in step S130, it is determined that the engine stall will not occur when the clutch 34 is fully engaged, and the value of the upshift prediction flag F1 is checked (step S130). S140). When the upshift prediction flag F1 is 0, that is, when it is predicted that the upshift of the gear stage of the transmission 40 will not be performed within the predetermined time T1, a complete engagement command is output to the clutch 34 (step S160). ) to end the routine.

When the upshift prediction flag F1 is 1 in step S140, that is, when it is predicted that the upshift of the gear stage of the transmission 40 will be performed within the predetermined time T1, the value of the low revolution prediction flag F2 is checked (step S150). ). When the low speed prediction flag F2 is 0, that is, after the upshift of the gear stage of the transmission 40, the rotation speed Ni of the input shaft 41 does not become less than the predetermined rotation speed Ni1 (when the clutch 34 is fully engaged). When it is predicted that the engine stall will not occur immediately, a complete engagement command is output to the clutch 34 (step S160), and this routine ends. On the other hand, when the low speed prediction flag F2 is 1, that is, after the upshift of the gear stage of the transmission 40, the rotation speed Ni of the input shaft 41 becomes less than the predetermined rotation speed Ni1 (the clutch 34 is fully engaged). Then, when it is predicted that the engine may stall), a slip engagement command is output to the clutch 34 (step S170), and this routine ends.

FIG. 5 shows the target gear stage Gs* and gear stage Gs of the transmission 40 of the embodiment, an upshift prediction flag F1, a low rotation prediction flag F2, a command to the clutch 34, the rotation speed Ne of the engine 22, and the rotation of the input shaft 41. 4 is a time chart showing an example of the state of the number Ni and the target speed Nitg; FIG. 6 shows the target gear stage Gs* of the transmission 40 of the comparative example, the gear stage Gs, the command to the clutch 34, the rotation speed Ne of the engine 22, the rotation speed Ni of the input shaft 41, and the target gear rotation speed Nitg. It is a time chart which shows an example. In the comparative example, in the clutch control routine of FIG. 3, the target shift stage rotation speed Nitg is less than the predetermined rotation speed Ni1 in the HV driving mode without considering the upshift prediction flag F1 and the low rotation prediction flag F2. Sometimes, the slip engagement command is output to the clutch 34, and the full engagement command is output to the clutch 34 when the target shift speed Nitg is equal to or greater than the predetermined speed Ni1. 5 and 6, when the gear stage Gs of the transmission 40 and the target gear stage Gs* match (when not upshifting) (other than times t12 to t13 in FIG. 5, time in FIG. 6 Except for t22 to t23), the rotation speed Ni of the input shaft 41 and the target shift stage rotation speed Nitg match.

In the comparative example, as shown in FIG. 6, when the target gear stage Gs* and the gear stage Gs of the transmission 40 are 1st gear and the target gear stage rotation speed Nitg increases to reach or exceed the predetermined rotation speed Ni1 (time t21 ), switching the command to the clutch 34 from the slip engagement command to the full engagement command. After that, when the target gear stage Gs* is switched from the 1st gear to the 2nd gear (time t22), an upshift of the gear stage is started. At this time, since the target shift stage rotation speed Nitg is less than the predetermined rotation speed Ni1, the command for the clutch 34 is switched from the complete engagement command to the slip engagement command. In this case, there is a possibility that the clutch 34 is switched from the fully engaged state to the slip engaged state during the upshift, causing a shift shock. For example, as shown in FIG. 6, when the clutch 34 is switched from the fully engaged state to the slip engaged state in the inertia phase (when the rotational speed Ni of the input shaft 41 is changing toward the target gear stage rotational speed Nitg), , the influence of the inertia of the mass body (the engine 22, the motor 30, etc.) on the input shaft 41 may change, and the change in the rotational speed Ni of the input shaft 41 may be disturbed, resulting in shift shock. Also, in the comparative example, the clutch 34 may be switched between the slip engagement state, the complete engagement state, and the slip engagement state in a short period of time. Then, when the upshift of the gear stage is completed (time t23), the gear stage Gs matches the target gear stage Gs*. After that, when the target gear position Gs* of the transmission 40 is the 2nd speed and the target gear position rotation speed Nitg increases to reach a predetermined rotation speed Ni1 or higher (time t24), the command to the clutch 34 is changed from the slip engagement command. Switch to full engagement command.

On the other hand, in the embodiment, as shown in FIG. 5, it is predicted that the target gear stage Gs* and the gear stage Gs of the transmission 40 are 1st gear, and that the upshift of the gear stage is performed within the predetermined time T1. When it is predicted that the rotation speed Ni of the input shaft 41 will be less than the predetermined rotation speed Ni1 after the upshift of the gear stage (time t10), the upshift prediction flag F1 and the low rotation prediction flag F2 are switched from the value 0 to the value 1. Then, when the upshift prediction flag F1 and the low speed prediction flag F2 are at a value of 1, when the target shift stage rotation speed Nitg increases and reaches a predetermined rotation speed Ni1 or higher (time t11), the command to the clutch 34 is slipped. Hold with an engagement command. After that, when the target gear stage Gs* is switched from 1st to 2nd (time t12), an upshift of the gear is started and an upshift of the gear (from 2nd to 3rd) is performed within a predetermined time T1. Since the upshift prediction flag F1 and the low revolution prediction flag F2 are not predicted to be performed, they are switched to the value 0. When the target gear stage Gs* is switched from the 1st gear to the 2nd gear, the target gear stage rotation speed Nitg is less than the predetermined rotation speed Ni1, so the command to the clutch 34 is held at the slip engagement command. As a result, it is possible to suppress the clutch 34 from switching between the fully engaged state and the slip engaged state during the upshift, thereby suppressing the occurrence of shift shock. In addition, switching the clutch 34 between the slip engagement state, the complete engagement state, and the slip engagement state in a short period of time can be suppressed. Then, when the upshift of the gear stage is completed (time t13), the gear stage Gs matches the target gear stage Gs*. After that, it is predicted that the target gear stage Gs* of the transmission 40 is 2nd and that the gear stage will be upshifted within a predetermined time T1, and the rotational speed Ni of the input shaft 41 after the gear stage upshift is reduced to a predetermined rotational speed. When it is predicted that it will not be less than Ni1 (time t14), the upshift prediction flag F1 is switched to the value 1 and the low revolution prediction flag F2 is held at the value 0. Then, when the upshift prediction flag F1 has a value of 1 and the low speed prediction flag F2 has a value of 0, when the target shift speed Nitg increases and reaches a predetermined speed Ni1 or higher (time t15), the clutch 34 is switched from a slip engagement command to a full engagement command.

In the embodiment, when the target gear stage Gs* and the gear stage Gs match, when the target gear stage rotation speed Nitg changes from less than the predetermined rotation speed Ni1 to the predetermined rotation speed Ni1 or more (time t11 , t15), when the upshift prediction flag F1 and the low speed prediction flag F2 are at a value of 1 (time t11), the command to the clutch 34 is held as a slip engagement command, and the upshift prediction flag F1 is at a value of 0. When the upshift prediction flag F1 has a value of 1 and the low speed prediction flag F2 has a value of 0 (time t15), the command to the clutch 34 is switched to the complete engagement command. Therefore, it is necessary to make it possible to predict that the gear position will be upshifted within a predetermined time T1 before the target gear speed Nitg reaches a predetermined speed Ni1 or more. Specifically, it is necessary to set the predetermined time T1. There is

In the hybrid vehicle 20 of the embodiment described above, when the target gear stage rotation speed Nitg, which is the rotation speed of the input shaft 41 corresponding to the target gear stage Gs* of the transmission 40, is less than the predetermined rotation speed Ni1, the clutch 34 Output a slip engagement command. Further, when the target gear stage rotation speed Nitg is equal to or greater than the predetermined rotation speed Ni1 and it is predicted that the upshift of the gear stage of the transmission 40 will not be performed within the predetermined time T1, or the upshift of the gear stage will not be performed for the predetermined time period. When it is predicted to be performed within T1 and when it is predicted that the rotation speed Ni of the input shaft 41 will not fall below the predetermined rotation speed Ni1 after the upshift of the gear stage, a complete engagement command is output to the clutch 34 . Further, when the target speed Nitg is equal to or higher than the predetermined speed Ni1, it is predicted that the upshift of the speed will be performed within the predetermined time T1, and the speed Ni of the input shaft 41 after the upshift of the speed is set to the predetermined value. When it is predicted that the rotation speed will be less than Ni1, a slip engagement command is output to the clutch 34 . As a result, the clutch 34 is switched from the slip engaged state to the fully engaged state when the target gear stage rotation speed Nitg reaches from less than the predetermined rotation speed Ni1 to the predetermined rotation speed Ni1 or more before the upshift of the gear stage. With time, the target gear speed Nitg becomes less than the predetermined rotation speed Ni1 due to a change of the target gear Gs* on the upshift side (for example, a change from 1st to 2nd), and the clutch 34 is switched again to the slip engagement state. , can be suppressed from occurring. That is, it is possible to suppress switching of the clutch from the fully engaged state to the slip engaged state during upshifting of the gear stage. As a result, it is possible to suppress the occurrence of a gear shift shock when the gear is upshifted. In addition, switching the clutch 34 between the slip engagement state, the complete engagement state, and the slip engagement state in a short period of time can be suppressed.

In the hybrid vehicle 20 of the embodiment, it is predicted whether or not the gear position of the transmission 40 will be upshifted within the predetermined time T1 based on the vehicle speed difference ΔV and the vehicle acceleration α. However, it may be possible to predict whether or not to perform an upshift of the gear stage of transmission 40 within predetermined time T1 based only on vehicle speed difference ΔV without considering vehicle acceleration α. In this case, when the vehicle speed difference ΔV is equal to or less than the threshold value ΔVref, it is predicted that the gear position of the transmission 40 will be upshifted within the predetermined time T1. It may be predicted that the stage upshift will not be performed within the predetermined time T1. Here, for example, several km/h to 10 km/h are used as the threshold value ΔVref.

In the hybrid vehicle 20 of the embodiment, the transmission 40 is configured as a four-speed automatic transmission. However, the transmission 40 may be configured as an automatic transmission with 3-speed, 5-speed, 6-speed, or the like.

The hybrid vehicle 20 of the embodiment is provided with the engine ECU 24 and the HVECU 70 . However, they may also be configured as a single electronic control unit.

In the embodiment, a hybrid vehicle 20 having an engine 22, a clutch 28, a motor 30, an inverter 32, a clutch 34, a transmission 40, a high voltage battery 60, a low voltage battery 62, and a DC/DC converter 64 is used. However, the hardware configuration of the hybrid vehicle 20 may be configured such that the clutch 28, the motor 30, the inverter 32, the high-voltage battery 60, and the DC/DC converter 64 are removed.

The correspondence relationship between the main elements of the embodiments and the main elements of the invention described in the column of Means for Solving the Problems will be described. In the embodiment, the engine 22 corresponds to the "engine", the transmission 40 corresponds to the "transmission", the clutch 34 corresponds to the "clutch", and the HVECU 70 and the engine ECU 24 correspond to the "control device".

Note that the correspondence relationship between the main elements of the examples and the main elements of the invention described in the column of Means for Solving the Problems is the Since it is an example for specifically explaining the mode for solving the problem, it does not limit the elements of the invention described in the column of the means for solving the problem. That is, the interpretation of the invention described in the column of Means to Solve the Problem should be made based on the description in that column, and the Examples are based on the description of the invention described in the column of Means to Solve the Problem. This is only a specific example.

Although the embodiments for carrying out the present invention have been described above, the present invention is not limited to such embodiments at all, and can be modified in various forms without departing from the scope of the present invention. Of course, it can be implemented.

INDUSTRIAL APPLICABILITY The present invention is applicable to the vehicle manufacturing industry and the like.

20 hybrid vehicle, 22 engine, 23 crankshaft, 23a crank position sensor, 24 engine ECU, 28 clutch, 30 motor, 30a rotation position sensor, 32 inverter, 34 clutch, 40 transmission, 41 input shaft, 41a rotation speed sensor, 42 output shaft, 42a rotation speed sensor, 46 drive shaft, 48 differential gear, 49 drive wheel, 60 high voltage battery, 61 high voltage side power line, 62 low voltage battery, 63 low voltage side power line, 64 DC/DC converter , 67a voltage sensor, 70 HVECU, 80 start switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 86 brake pedal position sensor, 88 vehicle speed sensor, 89 acceleration sensor.

Claims (4)

engine and
a transmission connected to the drive wheels;
a clutch provided between the engine and the transmission;
The transmission is controlled so that the gear stage becomes a target gear stage based on the accelerator operation amount and the vehicle speed, and the clutch is controlled to be the target rotation speed of the input shaft of the transmission corresponding to the target gear stage. a control device that establishes a fully engaged state when the gear rotation speed is equal to or higher than a predetermined rotation speed, and engages a slip engagement state when the target gear rotation speed is less than the predetermined rotation speed;
A vehicle comprising
The control device predicts that an upshift of the gear stage will be performed within a predetermined time when the target gear stage rotation speed is equal to or higher than the predetermined rotation number, and the rotation number of the input shaft after the upshift is set to the above-described value. when it is predicted that the number of rotations will be less than a predetermined number, the clutch is put into a slip engagement state;
vehicle. A vehicle according to claim 1,
The control device sets the target shift stage based on a shift line that is a relationship between the accelerator operation amount and the vehicle speed,
Further, the control device determines whether or not to perform the upshift of the gear stage within the predetermined time based on the vehicle speed difference between the current vehicle speed at the current accelerator operation amount and the vehicle speed on the shift line for the upshift. Predict,
vehicle. A vehicle according to claim 2,
The control device predicts, based on the vehicle speed difference and the acceleration of the vehicle, whether or not to perform an upshift of the gear stage within the predetermined time.
vehicle. A vehicle according to any one of claims 1 to 3,
When the clutch is in the slip engagement state, the control device controls the rotation speed, whichever is greater, between the predetermined rotation speed and a rotation speed higher than the rotation speed of the input shaft by a second predetermined rotation speed. controlling the engine so that it rotates;
vehicle.

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