The foregoing and further objects, features, and advantages of the invention will become apparent from the following description of preferred embodiments with reference to the accompanying drawing, wherein like numerals are used to represent like elements, and wherein:
Example embodiments of the present invention are described below with reference made to the accompanying drawings. In the description to follow, the same reference numerals and names are assigned to the same elements, and previously described elements are not repeatedly described.
Referring to
The vehicle shown in
The engine 1000 is an internal combustion engine that combusts a gas mixture of fuel injected from an injector (not illustrated) and air in a cylinder. The fuel combustion pushes a piston within the cylinder downward, causing rotation of the crankshaft. An electric motor may be used as a power source in place of, or in addition to, the engine 1000.
The automatic transmission 2000 is coupled to the engine 1000 via a torque converter 3200. The automatic transmission 2000 changes the rotational speed of the crankshaft to a desired rotational speed by forming a desired gear steps.
The output gear of the automatic transmission 2000 meshes with the differential gear 5000. The drive shaft 6000 is coupled to the differential gear 5000 by means of a spline fit or the like. Power is transmitted to the left and right front wheels 7000 via the drive shaft 6000.
A water temperature sensor 8002, a position switch 8006 of the gear shift lever 8004, an accelerator operation amount sensor 8010 of the accelerator pedal 8008, a pedal force sensor 8014 of the brake pedal 8012, a throttle opening sensor 8018 of the electronic throttle valve 8016, an engine speed sensor 8020, an input shaft rotational speed sensor 8022, an output shaft rotational speed sensor 8024, and an oil temperature sensor 8026 are connected to the ECU 8000 via a wiring harness.
The temperature sensor 8002 detects the temperature of the coolant of the engine 1000 (hereinafter coolant temperature), and sends a signal indicating the detection result to the ECU 8000. The position of the gear shift lever 8004 is detected by the position switch 8006, which sends a signal indicating the detection result to the ECU 8000. The gear step of the automatic transmission 2000 is selected in response to the position of the gear shift lever 8004. A configuration may be adopted in which it is possible to select a manual shift mode in which the gear step may be selected by an operation by the driver.
The accelerator operation amount sensor 8010 detects the operation of the accelerator pedal 8008, and sends a signal indicating the detection result to the ECU 8000. The pedal force sensor 8014 detects the pedal force of the brake pedal 8012 (force with which the driver presses on the brake pedal 8012) and sends a signal indicating the detection result to the ECU 8000.
The throttle-opening sensor 8018 detects the opening amount of the electronic throttle valve 8016, which is adjusted by an actuator, and sends a signal indicating the detection result to the ECU 8000. The electronic throttle valve 8016 adjusts the amount of air taken into the engine 1000 (output of the engine 1000).
In place of, or in addition to, the electronic throttle valve 8016, the amount of lift or the opening/closing phase of an intake valve (not illustrated) or exhaust valve (not illustrated) may be changed to adjust the amount of air taken into the engine 1000.
The engine speed sensor 8020 detects the rotational speed of the output shaft (crankshaft) of the engine 1000, and sends a signal indicating the detected rotational speed to the ECU 8000. The input shaft rotational speed sensor 8022 detects the rotational speed NI of the input shaft (turbine rpm NT of the torque converter 3200) and sends a signal indicating the detection result to the ECU 8000. The output shaft rpm sensor 8024 detects the rotational speed of the output shaft NO of the automatic transmission 2000 and sends a signal indicating the detection result to the ECU 8000.
The oil temperature sensor 8026 detects the temperature (oil temperature) of oil (automatic transmission fluid: ATF) used in the operation or lubrication of the automatic transmission 2000, and sends a signal indicating the detection result to the ECU 8000.
The ECU 8000 controls mechanisms to achieve a desired running condition of the vehicle, based on the signals sent from the coolant temperature sensor 8002, the position switch 8006, the accelerator operation amount sensor 8010, the pedal force sensor 8014, the throttle opening sensor 8018, the engine speed sensor 8020, the input shaft speed sensor 8022, the output shaft speed sensor 8024, the oil temperature sensor 8026 and the like, and also based on a map and a program stored in ROM.
In this embodiment, if the gear shift lever 8004 is in the D (drive) position, causing selection of the D (drive) shift range of the automatic transmission 2000, the ECU 8000 controls the automatic transmission 2000 to select an appropriate gear step from any of the first gear step to the sixth gear step. By selecting one of the first to sixth gear steps, the automatic transmission 2000 can transmit drive power to the front wheels 7000. In the D range, there may be additional gears, such as a seventh gear or a eighth gear, that are higher-speed gears than the sixth gear step. An appropriate gear step is formed based on a pre-established gear shift diagram determined experimentally using vehicle speed and accelerator operation amount as parameters.
As shown in
The ECU 8000 also has a traction control ECU, the TRC_ECU 8300, that controls the output torque when the vehicle is starting and accelerating, and a vehicle stability control ECU, the VSC_ECU 8400, which automatically controls the output torque of the engine 1000 to suppress skidding of the vehicle.
The engine ECU 8100, the ECT_ECU 8200, the TRC_ECU 8300, and the VSC_ECU 8400 are configured to enable mutual sending and receiving of signals. In this embodiment, a signal indicating the accelerator operation amount and a signal indicating the coolant temperature in the engine 1000 are sent to the ECT_ECU 8200 from the engine ECU 8100. A signal indicating the demanded torque amount established by the torque to be output from the engine 1000 is sent to the engine ECU 8100 from the ECT_ECU 8200. A signal indicating the torque demanded from the engine 1000 to achieve stable vehicle behavior is sent to the ECT_ECU 8200 from the TRC_ECU 8300 and the VSC_ECU 8400.
Referring to
The first set 3300 is a single-pinion type planetary gear mechanism. The first set 3300 includes a sun gear S (UD) 3310, a pinion gear 3320, a ring gear R (UD) 3330, and a carrier C (UD) 3340.
The sun gear S (UD) 3310 is coupled to the output shaft 3210 of the torque converter 3200. The pinion gear 3320 is supported by the carrier C (UD) 3340 to permit free rotation. The pinion gear 3320 meshes with the sun gear S (UD) 3310 and the ring gear R (UD) 3330.
The ring gear R (UD) 3330 is fixed to the gear case 3600 by the B3 brake 3630. The carrier C (UD) 3340 is fixed to the gear case 3600 by the B1 brake 3610.
The second set 3400 is a Ravigneaux-type planetary gear mechanism. The second set 3400 includes a sun gear S (D) 3410, a short pinion gear 3420, a carrier C (1) 3422, a long pinion gear 3430, a carrier C (2) 3432, a sun gear S (S) 3440, and ring gear R (1) (R (2)) 3450.
The sun gear S (D) 3410 is coupled to the carrier C (UD) 3340. The short pinion gear 3420 is supported by the carrier C (1) 3422 to permit free rotation. The short pinion gear 3420 meshes with the sun gear S (D) 3410 and the long pinion gear 3430. The carrier C (1) 3422 is coupled to the output gear 3500.
The long pinion gear 3430 is supported by the carrier C (2) 3432 to permit free rotation. The long pinion gear 3430 meshes with the short pinion gear 3420, the sun gear S (S) 3440, and the ring gear R (1) (R(2)) 3450. The carrier C (2) 3432 is coupled to the output gear 3500.
The sun gear S (S) 3440 is coupled to the output shaft 3210 of the torque converter 3200 by the C1 clutch 3640. The ring gear R(1) (R(2)) 3450 is fixed to the gear case 3600 by the B2 brake 3620, and is coupled to the output shaft 3210 of the torque converter 3200 by the C2 clutch 3650. The ring gear R(1) (R(2)) 3450 is coupled to the one-way clutch F 3660, and becomes unrotatable at the time of driving at the first gear step.
The one-way clutch F 3660 is provided in parallel with the B2 brake 3620. That is, the outer race of the one-way clutch F 3660 is fixed to the gear case 3600, and the inner race thereof is coupled via a rotating shaft to the ring gear R(1) (R(2)) 3450.
Referring to
The hydraulic circuit 4000 includes an oil pump 4004, a primary regulator valve 4006, a manual valve 4100, a solenoid modulator valve 4200, an SL1 linear solenoid (hereinafter referred to as SL(1)) 4210, an SL2 linear solenoid (hereinafter referred to as SL(2)) 4220, an SL3 linear solenoid (hereinafter referred to as SL(3)) 4230, an SL4 linear solenoid (hereinafter referred to as SL(4)) 4240, an SLT linear solenoid (hereinafter referred to as SLT) 4300, and a B2 control valve 4500.
The oil pump 4004 is coupled to the crankshaft of the engine 1000. The rotation of the crankshaft drives the oil pump 4004 and generates hydraulic pressure. The hydraulic pressure generated by the oil pump 4004 is adjusted by the primary regulator valve 4006, and line pressure is generated.
The primary regulator valve 4006 operates with the throttle pressure adjusted by the SLT 4300 as the pilot pressure. The line pressure is supplied to the manual valve 4100 via the line pressure oil passage 4010.
The manual valve 4100 includes a drain port 4105. The hydraulic pressure of the D range pressurized oil path 4102 or the R range pressurized oil path 4104 is discharged from the drain port. If the spool of the manual valve 4100 is in the D position, the line pressure oil path 4010 and the D range pressurized oil path 4102 are caused to communicate, so that hydraulic pressure is supplied to the D range pressurized oil path 4102. When this occurs, the R range pressurized oil path 4104 and the drain port 4105 are caused to communicate, so that the R range pressure of the R range pressurized oil path 4104 is discharged from the drain port.
If the spool of the manual valve 4100 is in the R position, the line pressure oil path 4010 and the R range pressurized oil path 4104 are caused to communicate, so that hydraulic pressure is supplied to the R range oil path 4104. When this occurs, the D range pressure oil path 4102 and the drain port 4105 are caused to communicate, so that the D range pressure of the D range pressurized oil path 4102 is discharged from the drain port 4105.
If the spool of the manual valve 4100 is in the N position, both the D range pressurized oil path 4102 and the R range pressurized oil path 4104 are caused to communicate with the drain port 4105, so that the D range pressure of the D range pressurized oil path 4102 and the R range pressure of the R range pressurized oil path 4104 are discharged from the drain port 4105.
The hydraulic pressure supplied to the D range pressurized oil path 4102 ultimately is supplied to the B1 brake 3610, the B2 brake 3620, the C1 clutch 3640, and the C2 clutch 3650. The hydraulic pressure supplied to the R range pressurized oil path 4104 is ultimately supplied to the B2 brake 3620.
The solenoid modulator valve 4200, taking the line pressure as the base pressure, adjusts the hydraulic pressure (solenoid modulator pressure) supplied to the SLT 4300 to a constant pressure.
The SL (1) 4210 adjusts the hydraulic pressure supplied to the C1 clutch 3640. The SL (2) 4220 adjusts the hydraulic pressure supplied to the C2 clutch 3650. The SL (3) 4230 adjusts the hydraulic pressure supplied to the B1 brake 3610. The SL (4) 4240 adjusts the hydraulic pressure supplied to the B3 brake 3630.
In response to a control signal from the ECU 8000 based on the accelerator operation amount detected by the accelerator operation amount sensor 8010, the SLT 4300 adjusts the solenoid modulator pressure and generates the throttle pressure. The throttle pressure is supplied to the primary regulator valve 4006 via the SLT oil path 4302. The throttle pressure is used as the pilot pressure for the primary regulator valve 4006.
The SL (1) 4210, the SL (2) 4220, the SL (3) 4230, the SL (4) 4240, and the SLT 4300 are controlled by control signals send from the ECU 8000.
The B2 control valve 4500 selectively supplies one of the hydraulic pressure from one of the D range pressurized oil path 4102 and the R range pressurized oil path 4104 to the B2 brake 3620. The R range pressurized oil path 4102 and the R range pressurized oil path 4104 are connected to the B2 control valve 4500. The B2 control valve 4500 is controlled by hydraulic pressure supplied from an SL solenoid valve (not illustrated) and the SLU solenoid valve (not illustrated), and by the impelling force of a spring.
With the SL solenoid valve off and the SLU solenoid valve on, the B2 control valve 4500 is in the left side condition shown in
With the SL solenoid valve on and the SLU solenoid valve off, the B2 control valve 4500 is in the right side condition shown in
Referring to
The engine ECU 8100 of the ECU 8000 includes a torque control section 8110. The torque control section 8110, upon receiving a demanded torque amount output from the ECT_ECU 8200, controls the degree of throttle opening of the electronic throttle valve 8016 and the ignition timing of the ignition plugs to output a torque corresponding to the demanded torque amount.
The ECT_ECU 8200 of the ECU 8000 includes a vehicle speed detection section 8210, an engaging force control section 8220, a driver demanded torque-setting section 8230, a torque demand section 8240, a torque-boost control section 8250, and a limiting section 8260.
The vehicle speed detection section 8210 calculates (detects) the vehicle speed from the output shaft rotational speed NO of the automatic transmission 2000. During and after completion of a gear shift the engaging force control section 8220 controls the engaging force of the B1 brake 3610, the B2 brake 3620, the B3 brake 3630, the C1 clutch 3640, and the C2 clutch 3650.
The driver demanded torque amount setting section 8230, based on the accelerator operation amount and the like, sets the driver demanded torque, which is the torque demanded by the driver. The driver demanded torque is set in response to the accelerator operation amount, so that it is greater the greater is the accelerator operation amount.
The torque demand section 8240 sets the demanded torque amount based on the driver demanded torque and the like, which is the torque demanded from the engine 1000. In steady-state running and the like, in which gear shifting is not done, the driver demanded torque is set as the demanded torque amount.
The torque boost control section 8250 executes the torque-boost control to increase the torque during the torque phase when up-shifting. The torque-boost control section 8250 includes a torque-boost setting section 8252 and a demanded torque-boost amount setting section 8254.
The torque boost setting section 8252 sets the amount of torque boost demanded from the engine 1000 in performing the torque-boost control. The torque-boost amount is set in response to the driver demanded torque, that is, to the accelerator operation amount.
The demanded torque-boost amount setting section 8254, during the torque phase when up-shifting, sets the demanded torque amount to increase to the torque-boosted amount pre-established in this embodiment. That is, the value that the demanded torque amount finally reaches is the torque-boosting amount.
When executing the torque-boost control, the torque demand section 8240 sets the demanded torque amount as the torque obtained by adding the demanded torque-boost amount to the demanded torque amount. That is, in performing the torque-boost control, torque-boosting is performed using the demanded drive torque as the reference.
When the shift lever 8004 is changed from the N (neutral) position to the D (drive) position, if the driver depresses the accelerator, the control section 8260 sets a torque that is different from the driver demanded torque that is set in response to the accelerator operation amount to control the torque output from the engine 1000.
In this embodiment the control section 8260 sets a smaller torque than the driver demanded torque. The torque set by the control section 8260 takes precedence over the driver demanded torque. That is, by the control section 8260 setting the torque, the torque output from the engine 1000 is automatically controlled, independently of the accelerator operation amount.
The TRC_ECU 8300 includes a torque setting section 8310. When the vehicle is starting or accelerating, if wheel slip is detected, the torque setting section 8310 of the TRC_ECU 8300 sets a torque that is different from the driver demanded torque, to stabilize the vehicle behavior. The torque setting section 8310 of the TRC_ECU 8300 sends a signal to the ECT_ECU 8200 indicating the torque to be set.
In this case, the torque section 8240 of the ECT_ECU 8200 sets the torque set by the torque setting section of the TRC_ECU 8300 as the demanded torque amount. That is, by the torque setting section 8310 of the TRC_ECU 8300 setting the torque, the torque output from the engine 1000 is automatically controlled, without dependence on the accelerator operation amount. Because known art can be used as a method for detecting wheel slipping, the details thereof will not be described herein.
The VSC_ECU 8400 includes a torque setting section 8410. When the vehicle is turning or the like, if skidding of the vehicle is detected, the torque setting section 8410 of the VSC_ECU 8400 sets a torque that is different from the driver demanded torque to stabilize the vehicle. A signal indicating the torque set by the torque setting section 8410 of the VSC_ECU 8400 is sent to the ECT_ECU 8200.
1 In this case, the torque demand section 8240 of the ECT_ECU 8200 sets the torque set by the torque setting section 8410 of the VSC_ECU 8400 as the demanded torque amount. That is, by the torque setting section 8410 setting the torque, the torque output from the engine 1000 is automatically controlled independently of the accelerator operation amount. Because known art can be used as a method for detecting skidding of the vehicle, the details thereof will not be described herein.
Referring to
At step S100, the ECU 8000 determines whether or not there is an up-shift request. Whether or not there is an up-shift request is determined based on the gear shift graph. If there is an up-shift request (YES at S100), processing proceeds to S102, and if not (NO at S100), processing ends.
At S102, the ECU 8000 determines whether the torque output from the engine 1000 is being automatically controlled independently of the accelerator operation amount. That is, it is determined whether at least one of the control section 8260 of the ECT_ECU 8200, the TRC_ECU 8300, and the VSC_ECU 8400 is setting the torque. If the torque is under automatic control (YES at S102), processing proceeds to S104, and if not (NO at S102), processing proceeds to S108.
At S104, the ECU 8000 prohibits the torque-boost control. At S106, the ECU 8000 boosts the torque without performing the torque-boost control during the torque phase, and makes an up-shift.
At S108, the ECU 8000 permits torque-boosting control. At S110, the ECU 8000 performs the torque-boost control and boosts the torque during the torque phase, and makes an up-shift.
The operation of the ECU 8000, which functions as the controller according to this embodiment, is described below, based on the foregoing structure and flowchart.
When the vehicle is moving, and an up-shift request occurs (YES at S100), a determination is made as to whether or not the torque output from the engine 1000 is being automatically controlled independently of the accelerator operation amount (S102).
If the torque output from the engine 1000 is not being automatically controlled (NO at S102), the torque-boost control is permitted (S108). For this reason, as shown by the solid line in
By doing this, as shown by the solid line in
If the torque output from the engine 1000 is being automatically controlled independently of the accelerator operation amount (YES at S102), as shown by the double-dot-dashed line in
In such a condition, if the torque-boost control establishes a demanded torque amount based on the driver demanded torque as a reference, the demanded torque amount changes suddenly from the torque set by automatic control to the driver demanded torque. In this case, there is a sudden increase in the torque output from the engine 1000 and a shock is generated.
In this case, when torque output from the engine 1000 is being automatically controlled (YES at S102), torque-boosting control is prohibited during the torque phase (S104). Up-shifting, therefore, is done without performing the torque-boost control during the torque phase. By doing this, it is possible to suppress sudden changes in the torque output from the engine 1000. For this reason, it is possible to suppress the occurrence of a shock when changing gears.
In an embodiment of the present invention as described above, when an up-shift request occurs if the torque output from the engine is automatically controlled independently of the accelerator operation amount, the torque-boost control is prohibited during the torque phase. By doing this, it is possible to suppress sudden changes from the torque set by automatic control to the driver demanded torque established in response to the accelerator operation amount. For this reason, it is possible to suppress sudden changes in the torque output from the engine, and as a result it is possible to suppress a shock when shifting gears.
Although in this embodiment of the present invention, automatic control of the torque is performed by at least one of the control section 8260 of the ECT_ECU 8200, the TRC_ECU 8300, and the VSC_ECU 8400, the constitution that performs automatic torque control is not restricted in this manner.
While the invention has been described with reference to what are considered to be preferred embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments or constructions. On the contrary, the invention is intended to cover various modifications and equivalent arrangements. In addition, while the various elements of the disclosed invention are shown in various combinations and configurations, which are exemplary, other combinations and configurations, including more, fewer, or only a single element, are also within the spirit and scope of the invention.
Number | Date | Country | Kind |
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2006-209829 | Aug 2006 | JP | national |