JP2018135987A - Control device and control method of vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce energy consumption while taking into consideration re-startability.SOLUTION: A neutral state of an automatic transmission TM can be selectively set to a first neutral state in which a part 31 out of a plurality of fastening elements 31, 32 is fastened, and the other fastening element 32 is released, and a second neutral state in which a fastening element whose number is smaller than that in the first neutral state out of the plurality of fastening elements 31, 32 is fastened, and the other of the fastening elements 31, 32 is released. When a prescribed condition including the fact that at least a parking range or a neutral range is selected as a shift range of the automatic transmission TM, and that a drive source (engine 1) is in an automatic stop, is established, the automatic transmission TM is brought into the second neutral state, and when the prescribed condition is not established, the automatic transmission is brought into the first neutral state.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a vehicle control device and a control method configured to be able to control a neutral state of an automatic transmission by an actuator.

  Patent Document 1 discloses that after the engine is automatically stopped in the forward travel range, when the shift range is switched to the park range, the stopped state of the engine that is the drive source is maintained.

  Patent Document 2 discloses that, in an automatic transmission having a stepped transmission mechanism, when the automatic transmission is set to a neutral state, the engaged state of at least one clutch element is maintained in consideration of restartability. ing.

JP 2007-239679 (paragraph 0013) JP 04-300452 (paragraph 0007)

  When the engine is stopped, the oil pump using the engine as a power source cannot be operated. Therefore, in order to maintain restartability, in order to maintain the engaged state of one or more clutch elements during the automatic stop of the engine, an oil pump that uses a power source other than the engine, for example, an electric oil pump is provided. This requires the hydraulic pressure of the clutch element to be generated. Here, it is not preferable to operate the electric oil pump for a long time from the viewpoint of energy saving. Therefore, it is conceivable to reduce the number of clutch elements to be engaged and reduce the load of the electric oil pump. However, in this case, the number of clutch elements that must be engaged when restarting increases, There is concern that startability cannot be obtained.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a vehicle control device and a control method that can reduce energy consumption while considering recurring performance.

  In one aspect, the present invention provides a drive source, an automatic transmission connected to the drive source and having a plurality of fastening elements, and supplying hydraulic oil to the plurality of fastening elements of the automatic transmission while the drive source is stopped. Provided is a vehicle control device including a possible oil pump. As a neutral state of the automatic transmission, a first neutral state in which some of the plurality of fastening elements are fastened and a second neutral state in which the number of fastening elements of the fastening elements is smaller than that in the first neutral state are selectively set. A control unit capable of automatically shifting when a condition including at least a park range or a neutral range is selected as the shift range of the automatic transmission when the drive source is automatically stopped. The machine is in the second neutral state.

  Furthermore, in another embodiment, the hydraulic fluid can be supplied to the driving source, the automatic transmission having a plurality of fastening elements connected to the driving source, and the plurality of fastening elements of the automatic transmission while the driving source is stopped. An oil pump and a vehicle control method are provided. As a neutral state of the automatic transmission, a first neutral state in which some of the plurality of fastening elements are fastened and a second neutral state in which the number of fastening elements of the fastening elements is smaller than that in the first neutral state are selectively set. The automatic transmission is set to the second neutral state when a condition including that at least the park range or the neutral range is selected as the shift range of the automatic transmission is satisfied when the drive source is automatically stopped.

  According to the above aspect, the neutral state of the automatic transmission can be selected from the first neutral state and the second neutral state, and at the time of automatic stop of the drive source, at least the park range or neutral as the shift range of the automatic transmission. The automatic transmission is set to the second neutral state when a condition including that the non-traveling range of the range is selected is established. In this way, basically, the automatic transmission is set to the first neutral state to prepare for a sudden restart, but when the possibility of a sudden start is low, the number of fastening elements to be engaged is less than the first neutral state. As a result, the hydraulic oil pressure and flow rate required to maintain the engaged state can be reduced, the load on the oil pump can be reduced, and the energy consumption can be reduced.

FIG. 1 is a schematic diagram showing an overall configuration of a vehicle drive system according to an embodiment of the present invention. FIG. 2 is a schematic view showing a configuration of a stepped transmission mechanism according to the embodiment. FIG. 3 is a fastening table showing a combination of fastening and releasing for each gear stage of the stepped transmission mechanism according to the embodiment. FIG. 4 is a fastening table showing a combination (neutral pattern) of fastening and releasing in the neutral state of the stepped transmission mechanism according to the embodiment. FIG. 5 is a flowchart showing an overall flow of idle stop control according to the embodiment. FIG. 6 is a flowchart showing the contents of the neutral state control routine of the idle stop control described above. FIG. 7 is a schematic diagram showing an overall configuration of a vehicle drive system according to another embodiment of the present invention.

  Embodiments of the present invention will be described below with reference to the drawings.

(Configuration of vehicle drive system)
FIG. 1 schematically shows an overall configuration of a vehicle drive system P according to an embodiment of the present invention.

  The vehicle drive system P according to the present embodiment includes an internal combustion engine (hereinafter simply referred to as “engine”) 1 as a drive source, and a torque converter 2 and an existence on a power transmission path that connects the engine 1 and the left and right drive wheels 7. A step transmission mechanism 3 is provided. The torque converter 2 and the stepped transmission mechanism 3 constitute an automatic transmission TM of the vehicle drive system P. The automatic transmission TM converts the rotational power input from the engine 1 to the torque converter 2 at a predetermined gear ratio by the stepped transmission mechanism 3 and outputs it to the drive wheels 7 via the differential gear 5.

  The torque converter 2 includes a pump impeller 21 connected to the input shaft of the torque converter 2 and a turbine runner 22 connected to the output shaft of the torque converter 2, and the input rotational power is converted into a mechanical action of fluid. Via the output shaft. The torque converter 2 further includes a lock-up clutch 23 connected to the output shaft. By setting the lock-up clutch 23 to the engaged state, the input shaft and the output shaft are directly connected, and transmission loss due to fluid connection is reduced. It is possible. Engagement and release of the lock-up clutch 23 are switched by controlling the hydraulic pressure acting on the lock-up clutch 23.

  The stepped transmission mechanism 3 includes a plurality of planetary gear mechanisms and a plurality of frictional engagement elements. The frictional engagement element may be a clutch element or a brake element, and the combination of engagement and release of a plurality of frictional engagement elements including the frictional engagement elements 31 to 33 specifically shown in FIG. 1 is changed. Thus, the gear ratio via the planetary gear mechanism can be switched. In the present embodiment, the stepped transmission mechanism 3 includes a plurality of clutch elements including the clutch element 31 and a plurality of brake elements including the brake elements 32 and 33. The clutch element 31 and the brake elements 32 and 33 constitute a “fastening element” according to the present embodiment.

  The automatic transmission TM has a drive range (hereinafter referred to as “D range”), a reverse range (hereinafter referred to as “R range”), a neutral range (hereinafter referred to as “N range”), and a park range (hereinafter referred to as “P range”) as shift ranges. ") Is set. The D range and the R range correspond to the travel range, and the N range and the P range correspond to the non-travel range. The shift range of the automatic transmission TM is selected by the driver using a shift lever.

  The rotational power output from the automatic transmission TM is transmitted to the drive shaft 6 through the final gear train 4 and the differential 5 set to a predetermined reduction ratio, and the drive wheels 7 are rotated.

  In the present embodiment, an electric oil pump is used as a source of hydraulic pressure that acts on the lock-up clutch 23 of the torque converter 2 and the frictional engagement elements (including the clutch element 31 and the brake elements 32 and 33) of the stepped transmission mechanism 3. 51 is provided. The oil pump 51 incorporates an electric motor as a motive power source, operates with electric power supplied from a battery (not shown), boosts the operating oil to a predetermined pressure, and boosts the operating oil through the hydraulic control circuit 61. Is supplied to each part of the automatic transmission TM. FIG. 1 shows a hydraulic pressure supply path from the hydraulic pressure control circuit 61 to each part by a dotted line with an arrow.

  The hydraulic control circuit 61 includes a plurality of solenoid valves as actuators, and basically, when the shift range is the N range or the P range, some of the three frictional engagement elements 31 to 33 (one or two). In the case of two frictional engagement elements, for example, by applying hydraulic pressure to the brake elements 32 and 33, some of these frictional engagement elements are fastened and other frictional engagement elements (for example, the clutch element 31) are applied. ) Is released. Thereby, automatic transmission TM will be in a neutral state, and transmission of rotational power from engine 1 to drive wheel 7 will be intercepted.

  On the other hand, when the shift range is the D range, by applying the hydraulic pressure to all of the three friction engagement elements 31 to 33 at the first speed where the gear ratio of the automatic transmission TM is the largest among the forward gears, The clutch element 31 and the brake elements 32 and 33 are fastened. Therefore, when the shift range is changed from the N range or the P range to the D range when starting from the stop state, some frictional engagement elements that are already engaged (specifically, the brake elements 32, 33). ) Is maintained, and the rest (clutch element 31) is switched from the released state to the engaged state.

(Specific example of stepped transmission mechanism)
FIG. 2 shows a specific example of the stepped transmission mechanism 3 applicable to the automatic transmission TM according to the present embodiment.

  The stepped transmission mechanism 3 includes a first planetary gear (PG1) 31, a second planetary gear (PG2) 32, a third planetary gear (PG3) 33, and a fourth planetary gear (PG4) 34, and these four planetary gears 31 to 34 are: Sun gears 31S to 34S, carriers 31C to 34C, and ring gears 31R to 34R are provided.

  The stepped transmission mechanism 3 further includes three clutch elements K27, K38, and K81 for intermittently or fixing the elements of the first to fourth planetary gears 31 to 34, and three brake elements B05, B06, and B08. By selectively interrupting or fixing these frictional engagement elements, the first to ninth speeds of 9 forward speeds and 1 reverse speed are achieved.

  Here, the first planetary gear 31 has a sun gear 31S, a carrier 31C and a ring gear 31R, the second planetary gear 32 has a sun gear 32S, a carrier 32C and a ring gear 32R, and the third planetary gear 33 has a sun gear 33S and a carrier 33C. The fourth planetary gear 34 includes a sun gear 34S, a carrier 34C, and a ring gear 34R.

  The stepped transmission mechanism 3 includes an input shaft 30A for inputting rotational power of the engine 1 via the torque converter 2, an output shaft 30B for outputting rotational power after shifting by the stepped transmission mechanism 3, and first to fourth. And intermediate shafts 30C and 30D for connecting specific elements of the planetary gears 31 to 34. Then, required elements of the first to fourth planetary gears 31 to 34 are selectively connected to form a required power transmission path and a specific shift speed is configured.

  Specifically, in the present embodiment, a sun gear 31S of the first planetary gear 31 and a carrier 34C of the fourth planetary gear 34 are directly coupled to the input shaft 30A of the stepped transmission mechanism 3. Therefore, the sun gear 31S and the carrier 34C always rotate integrally with the input shaft 30A. Further, the carrier 31C of the first planetary gear 31 is coupled to the input shaft 30A via the first clutch K81.

  A carrier 33 </ b> C of the third planetary gear 33 is directly coupled to the output shaft 30 </ b> B of the stepped transmission mechanism 3. Therefore, the carrier 33C always rotates integrally with the output shaft 30B. Further, a ring gear 34R of the fourth planetary gear 34 is coupled to the output shaft 30B via the second clutch K27.

  The ring gear 31R of the first planetary gear 31 and the carrier 32C of the second planetary gear 32 are coupled to each other via the intermediate shaft 30C, and the ring gear 31R and the carrier 32C always rotate integrally.

  The ring gear 32R of the second planetary gear 32, the sun gear 33S of the third planetary gear 33, and the sun gear 34S of the fourth planetary gear 34 are coupled to each other via an intermediate shaft 30D. The ring gear 32R, the sun gear 33S, and the sun gear 34S are , Always rotate integrally.

  Further, the carrier 31C of the first planetary gear 31 is coupled to the intermediate shaft 30D via the third clutch K38. The carrier 31C of the first planetary gear 31 is connected via the third brake B08, the sun gear 32S of the second planetary gear 32 is connected via the first brake B05, and the ring gear 33R of the third planetary gear 33 is connected to the second brake B06. Both are coupled to the transmission case 3A.

  Thus, in this embodiment, the combination of engagement and release of the first to third clutches K81, K27, and K38, which are clutch elements, and the first to third brakes B05, B06, B08, which are brake elements, is used. By selecting, one of the first to ninth speeds of 9 forward speeds and 1 reverse speed is achieved.

  FIG. 3 is an engagement table showing combinations of engagement and disengagement of the frictional engagement elements for each gear position in the stepped transmission mechanism 3 according to the present embodiment. In the figure, a circle indicates that the frictional engagement element is engaged, and a blank indicates that it is released. The indications “1” to “9” in the column of the number of steps indicate the first to ninth forward shift speeds, respectively, and the “Rev” indication indicates the reverse speed.

  As shown in FIG. 3, in this embodiment, a specific gear stage is established by engaging three frictional engagement elements among the six frictional engagement elements K81, K27, K38, B05, B06, and B08 and releasing the rest. To achieve. Specifically, in order to achieve the first forward speed, the first brake B05, the second brake B06, and the third clutch K38 are engaged, and the rest (the third brake B08, the first clutch K81, and the second clutch K27) are used. Let go. The combination of the frictional engagement elements that are engaged and released when the other shift speeds are achieved is as shown in FIG.

  FIG. 4 is a fastening table showing a neutral pattern of the stepped transmission mechanism 3 according to the present embodiment. FIG. 4 shows a pattern when the first neutral state is selected as the neutral state of the automatic transmission TM. The case where the second neutral state is selected will be described later.

  In the present embodiment, when the automatic transmission TM is set to the neutral state (first neutral state), all of the six frictional engagement elements K81, K27, K38, B05, B06, and B08 are not released but partially The frictional engagement elements (specifically, two) are maintained in the engaged state. Although the neutral state can be achieved by any of the 13 patterns shown in FIG. 4, in the present embodiment, the time required for the transition to the first forward speed or the reverse gear is taken into consideration. An eighth pattern is employed in which the first brake B05 and the second brake B06 are engaged and the third clutch K38 is released. As another embodiment, when the number of frictional engagement elements to be maintained in the engagement state is one when the neutral state is established, six neutral patterns equal to the number of frictional engagement elements are conceivable.

(Control system configuration and basic operation)
Operations of the engine 1 and the automatic transmission TM are controlled by the controller 101. The controller 101 is configured as an electronic control unit, and includes a central processing unit (CPU), various storage devices such as a RAM and a ROM, and a microcomputer including an input / output interface.

  The controller 101 receives a detection signal from an operation state sensor that detects the operation state of the engine 1, executes a predetermined calculation based on the operation state, and determines the fuel injection amount, fuel injection timing, ignition timing, and the like of the engine 1. Set.

  In the present embodiment, in addition to the normal engine control routine, the controller 101 determines whether or not a predetermined idle stop condition is satisfied. If the idle stop condition is satisfied, the controller 101 executes the idle stop, and the engine 1 Is automatically stopped. After the idle stop, the controller 101 determines whether or not a predetermined idle stop cancel condition is satisfied. If the idle stop cancel condition is satisfied, the controller 101 cancels the idle stop and restarts the engine 1.

  In the present embodiment, as a driving state sensor, an accelerator sensor 111 that detects an accelerator pedal operation amount (hereinafter referred to as “accelerator opening”) APO by a driver, a rotational speed sensor 112 that detects a rotational speed of the engine 1, an engine cooling In addition to a cooling water temperature sensor 113 for detecting the water temperature TW, an air flow meter, a throttle sensor, a fuel pressure sensor, an air-fuel ratio sensor, and the like (not shown) are provided. In the present embodiment, the rotational speed sensor 112 is configured by a crank angle sensor, and the engine controller 101 determines the rotational speed of the engine 1 based on a reference crank angle output from the crank angle sensor or a signal for each unit crank angle. The engine speed NE (hereinafter referred to as “engine speed”) NE is calculated.

  Further, in relation to the control of the automatic transmission TM, a vehicle speed sensor 211 that detects a vehicle traveling speed (hereinafter referred to as “vehicle speed”) VSP, and a brake sensor that detects a brake pedal force BPF that indicates a depression amount of a brake pedal by a driver. 212, the input side rotational speed sensor 213 for detecting the rotational speed of the input shaft of the stepped transmission mechanism 3 (the rotational speed per unit time, hereinafter referred to as “shift input rotational speed”) Ntmi, and the output of the stepped transmission mechanism 3 An output side rotational speed sensor 214 for detecting the rotational speed of the shaft (the rotational speed per unit time, hereinafter referred to as “shift output rotational speed”) Ntmo, and an oil temperature sensor for detecting the temperature Toil of the hydraulic oil of the automatic transmission TM 215, a forward vehicle recognition sensor 216 for recognizing the presence of the forward vehicle, and a shift position for detecting the position of the shift lever (hereinafter referred to as “shift position”) In addition to capacitors 219 are provided, the seat belt switch 217 which outputs a signal indicating the wearing state of the seat belt, the parking brake switch 218 for outputting a signal indicating the operating state of the parking brake is provided to the driver.

  In the present embodiment, the forward vehicle recognition sensor 216 is a camera incorporating an image sensor made up of a CCD element or the like, and the controller 101 analyzes the captured image by a predetermined image analysis routine, thereby determining whether there is a forward vehicle. Can be determined. The forward vehicle recognition sensor 216 is not limited to this, and may be a radar or an information communication device. A millimeter wave radar can be employed as the radar, and a navigation device, an Internet terminal, and an inter-vehicle communication device can be employed as the information communication device. The controller 101 has a forward vehicle determination value that is set to be switchable between 0 and 1, and when the presence of the forward vehicle is not detected, the forward vehicle determination value is set to 0 and the presence of the forward vehicle is determined. If detected, the forward vehicle determination value is set to 1. As described above, in the present embodiment, the presence of the forward vehicle is recognized, but an inter-vehicle distance sensor may be employed instead of the forward vehicle recognition sensor 216 to measure the inter-vehicle distance from the forward vehicle. .

  The seat belt switch 217 outputs an ON signal as a seat belt signal when the driver's seat belt is worn. The parking brake switch 218 outputs an ON signal as a parking brake signal when the parking lever is pulled up by the driver and the parking brake is in an activated state.

  The controller 101 determines the shift range selected by the driver based on the signal from the shift position sensor 219, sets the gear position of the automatic transmission TM based on the accelerator opening APO, the vehicle speed VSP, etc. The state of a plurality of frictional engagement elements constituting the mechanism 3 is controlled. Specifically, with a hydraulic pressure generated by the oil pump 51 as a source pressure, a predetermined hydraulic pressure corresponding to the shift range and the shift stage is applied to the clutch element 31, the brake elements 32, 33, and other friction engagement elements. In addition, a control signal is output to the hydraulic control circuit 61.

  In the present embodiment, the hydraulic control circuit 61, the controller 101, the forward vehicle recognition sensor 216, the seat belt switch 217, the parking brake switch 218, and the shift position sensor 219 constitute a “vehicle control device”. The function of “part” is realized. The controller 101 controls the neutral state of the automatic transmission TM when the engine 1 is idle stopped. More specifically, neutral state control is performed to switch the number of frictional engagement elements to be engaged in the idling stop. Hereinafter, the idle stop control according to the present embodiment will be described.

(Contents of idle stop control)
FIG. 2 shows the overall flow of the idle stop control according to this embodiment.

  In S101, it is determined whether or not a predetermined idle stop condition is satisfied for the engine 1. The idle stop condition is satisfied, for example, when the accelerator pedal is returned, the vehicle speed VSP is equal to or lower than a predetermined value VSP1, and the brake pedal is depressed. The predetermined value VSP1 is a value by which it can be determined that the vehicle has stopped or is stopped. If the idle stop condition is satisfied, the process proceeds to S102. If the idle stop condition is not satisfied, the process of S101 is repeated, and the process waits until the idle stop condition is satisfied.

  In S102, the fuel supply to the engine 1 is stopped, and the engine 1 is stopped regardless of the driver's operation.

  In S103, the process proceeds to a neutral state control routine described later, and the neutral state of the automatic transmission TM is controlled.

  In S104, it is determined whether a predetermined idle stop cancellation condition is satisfied. The idle stop cancellation condition is satisfied, for example, when the brake pedal is returned after the idle stop. When the idle stop cancellation condition is satisfied, the process proceeds to S105, and when it is not satisfied, the process returns to S103 and the neutral state control of the automatic transmission TM is continued.

  In S105, the fuel supply to the engine 1 is resumed and the engine 1 is started again.

  In S106, the automatic transmission TM is set to the forward first speed in preparation for re-start (FIG. 3). Specifically, when the automatic transmission TM is set to the first neutral state by the neutral state control, the clutch element 31 is switched from the released state to the engaged state while maintaining the engaged state of the brake elements 32 and 33. On the other hand, when the automatic transmission TM is set to the second neutral state, all of the clutch element 31 and the brake elements 32 and 33 are switched from the released state to the engaged state. In the present embodiment, the eighth pattern of the fastening table shown in FIG. 4 is adopted as the pattern of the first neutral state, and the third clutch K38 corresponds to the clutch element 31 among the friction fastening elements shown in FIG. The brake B05 and the second brake B06 correspond to the brake elements 32 and 33, respectively.

  FIG. 3 shows the specific contents of the neutral state control routine (S103).

  In S201, the shift range and the forward vehicle determination value are read, and the display values of the seat belt signal and the parking brake signal are read.

  In S202, it is determined whether or not the shift range of the automatic transmission TM is a park range (P range). If it is the P range, the process proceeds to S204, and if it is not the P range, the process proceeds to S203.

  In S203, it is determined whether or not the shift range of the automatic transmission TM is a neutral range (N range). If it is the N range, the process proceeds to S204, and if it is not the N range, the process proceeds to S208.

  As described above, in this embodiment, when the shift range selected by the driver is one of the non-traveling ranges (P range or N range), the process proceeds to S204, while the other D range or R range. In this case, the process proceeds to S208, and the idle stop control for the travel range is executed.

  In S204, it is determined whether or not a predetermined condition described below is satisfied. If at least one of these predetermined conditions is satisfied, the process proceeds to S205, and if any predetermined condition is not satisfied, the process proceeds to S207. That is, in the present embodiment, when the idle stop condition is satisfied (when the engine 1 as the driving source is automatically stopped), the shift range includes the P range or the N range, and the predetermined condition is satisfied. When a condition (hereinafter, sometimes referred to as “transition condition” or “second neutral state transition condition”) is satisfied, the process proceeds to S205.

  The first is whether or not the seat belt in the driver's seat has been released, and is determined based on the display value of the seat belt signal. When the seatbelt of the driver's seat is released and the displayed value indicates the off state of the seatbelt switch 217, it is determined that there is a low possibility of sudden restart after the vehicle stops.

  The second is whether or not the parking brake has been raised, and is determined based on the display value of the parking brake signal. When the parking brake is raised and the displayed value indicates the on state of the parking brake switch 218, it is determined that the possibility of a sudden re-start is low after the vehicle stops.

  The third is whether or not there is a forward vehicle, and is determined based on the forward vehicle determination value. When there is a vehicle ahead (or the distance between the vehicle and the vehicle ahead is a predetermined value or less), it is determined that the possibility of a sudden re-start is low after stopping.

  The fourth is whether or not a predetermined time has elapsed after selection of the non-traveling range. When the controller 101 has a timer function, the timer is reset when the non-driving range is selected (S202, S203). Thus, the determination can be made based on the timer value. Thus, when a predetermined time has elapsed after the non-traveling range is selected, the neutral state of the automatic transmission TM is changed from the first neutral state (S207) to the second neutral state (S205).

  In S205, the second state (second neutral state) is selected as the neutral state of the automatic transmission TM.

  In S206, the output of the oil pump 51 is set to the output for the second neutral, and the output of the oil pump 51 is reduced as compared with the case where the automatic transmission TM is set to the first neutral state (S207).

  In S207, the first state (first neutral state) is selected as the neutral state of the automatic transmission TM.

  In the present embodiment, when the first neutral state is selected, some of the three frictional engagement elements B05, B06, and K38 that are engaged at the first forward speed (first brake B05 and second brake B06). And the rest (the first clutch K38) is released. On the other hand, when the second neutral state is selected, all the three frictional engagement elements B05, B06, and K38 are released. As described above, when the automatic transmission TM is set to the second neutral state, the number of frictional engagement elements to be engaged is reduced compared to the case where the automatic transmission TM is set to the first neutral state. Specifically, the number of clutch elements and brake elements to be engaged is 2 in the first neutral state, and 0 in the second neutral state.

  In S208, the idling stop control for the driving range is executed. Specifically, the combination of engagement and disengagement of the frictional engagement elements is set to the first forward speed combination or the first neutral state is awaited. In the first forward speed combination, both the clutch element 31 (K38) and the brake elements 32 and 33 (B05, B06) are engaged.

  In the present embodiment, the function of the “control unit” is realized by the processing of S101 and S104 in the flowchart shown in FIG. 5 and the processing of S201 to S206 in the flowchart shown in FIG.

(Explanation of effects)
The vehicle control apparatus according to the present embodiment is configured as described above, and effects obtained by the present embodiment will be described below.

  First, the neutral state of the automatic transmission TM can be selected from the first neutral state (S207) and the second neutral state (S205), and the shift of the automatic transmission TM is performed when the idle stop condition for the engine 1 is satisfied. When the condition including that the range is the non-traveling range of the P range or the N range is satisfied (S101, S202, S203), the second neutral state is selected. As a result, at the time of idling stop, basically, the automatic transmission TM is set to the first neutral state to prepare for a sudden re-start after stopping, and when the possibility of a sudden start is low, the friction engagement to be engaged. By reducing the number of elements 31 to 33 (K38, B05, B06) from the first neutral state, the hydraulic oil pressure and flow rate required to maintain the engaged state are reduced, and the load on the oil pump 51 is reduced. Thus, energy consumption can be reduced (effects corresponding to claims 1, 2, 7 and 8).

  Second, as a condition for selecting the second neutral state, it is determined that a predetermined time has elapsed after the non-traveling range of the P range or the N range is selected (S204). After the change, when the driving range is changed again by the driver's change of mind or the like, the neutral state is frequently switched between the first state and the second state, thereby avoiding an increase in energy consumption. (Effect corresponding to claim 3).

  Here, it is possible to avoid frequent switching of the neutral state when waiting for a signal by setting the predetermined time to a time corresponding to waiting for a signal (which may vary depending on the country, for example, 1 minute or more). can do.

  Thirdly, when the seatbelt of the driver's seat is released, it can be determined that the possibility of a sudden re-start is low. Therefore, as a condition for selecting the second neutral state, the seatbelt of the driver's seat is used. By determining that the vehicle has been released (S204), avoiding frequent switching of the neutral state between the first state and the second state due to the driver's change of mind, etc. The second neutral state can be selected at an early stage, and energy consumption can be effectively reduced (effect corresponding to claim 4).

  Fourth, when the parking brake is raised, it can be determined that the possibility of a sudden re-start is low, so it is determined that the parking brake has been raised as a condition for selecting the second neutral state. Thus (S204), it is possible to select the second neutral state as early as possible while avoiding frequent switching of the neutral state due to the driver's change of mind, etc., and to effectively reduce energy consumption. (Effect corresponding to claim 5).

  Fifth, when the vehicle ahead is present or the distance to the vehicle ahead is relatively close, it is possible to determine that the possibility of sudden restart is low, so the second neutral state is selected. By determining that there is a vehicle ahead as a condition (S204), after the shift range is changed to the non-traveling range, the second neutral state can be quickly selected to reduce energy consumption (invoice). Effect corresponding to item 6).

(Description of other embodiments)
FIG. 7 is a schematic diagram showing an overall configuration of a vehicle drive system P according to another embodiment of the present invention.

  In the present embodiment, a continuously variable transmission mechanism 8 is employed as the transmission mechanism of the automatic transmission TM in place of the stepped transmission mechanism 3 in the previous embodiment (FIG. 1).

  The automatic transmission TM according to this embodiment includes a torque converter 2 and a continuously variable transmission mechanism (hereinafter referred to as “variator”) as a main transmission in order from the engine 1 side on a power transmission path connecting the engine 1 and the drive wheels 7. 8) and an auxiliary transmission 9 are provided.

  The variator 4 includes a primary pulley 81 and a secondary pulley 82 as transmission elements, and includes a metal belt 83 wound around the pulleys 81 and 82, and the metal belt 83 contacts the primary pulley 81 and the secondary pulley 82. By changing the ratio of the part radii, it is possible to change the transmission ratio steplessly. The transmission ratio of the variator 8 is controlled by adjusting the hydraulic pressure acting on the movable sheaves of the primary pulley 81 and the secondary pulley 82 and changing the width of the V groove formed between the movable sheave and the fixed sheave.

  The auxiliary transmission 9 is configured as a stepped transmission mechanism, and includes a plurality of planetary gear mechanisms and a plurality of frictional engagement elements. The sub-transmission 9 can change the gear ratio of the sub-transmission 9 by changing the combination of engagement and release of the frictional engagement elements, thereby changing the overall transmission ratio of the automatic transmission TM. . Rotation between the input shaft and the output shaft is performed by engaging one of the clutch elements 91 and 92 (for example, the clutch element 91) and releasing the other (for example, the clutch element 92) among the friction engagement elements. The transmission of power is cut off and the automatic transmission TM is set to the neutral state.

  Then, the idle stop control is executed by the same flow as shown in FIG. 2, and the neutral state control is executed by the same flow as shown in FIG. However, in the present embodiment, when the neutral state of the automatic transmission TM is set to the first state (first neutral state), the clutch element 91 is kept engaged among the clutch elements 91 and 92, and only the clutch element 92 is maintained. On the other hand, when the second state (second neutral state) is set, both clutch elements 91 and 92 are released.

  Thus, by combining with the sub-transmission 9 that is a stepped transmission mechanism, the same effect as in the previous embodiment can be obtained even in the automatic transmission TM including the continuously variable transmission mechanism 8. Specifically, at the time of idling stop, basically, the automatic transmission TM is set to the first neutral state to prepare for a sudden re-start after stopping, and when the possibility of sudden start is low, the engagement state is set. By reducing the number of clutch elements 91 and 92 from the first neutral state, the hydraulic oil pressure and flow rate required to maintain the engaged state are reduced, the load on the oil pump 51 is reduced, and energy consumption is reduced. can do. As an actuator for controlling the engagement and release of the frictional engagement element, a type in which a current or voltage is supplied when the frictional engagement element is engaged, for example, a normally / low type solenoid valve is used. In this case, power consumed by the actuator can be reduced.

  In the above description, the case where the “vehicle control device” is integrally realized by the controller 101 has been described. However, the present invention is not limited to this, and the “vehicle control device” can be realized by distributing the functions to a plurality of controllers. For example, when an engine controller for controlling the engine 1 and a transmission controller for controlling the automatic transmission TM are provided, the engine controller and the transmission controller can be used in cooperation, and only the transmission controller can be used. You can also. In the case of cooperation between the engine controller and the transmission controller, it is possible to execute the process of S103 in the process shown in FIG. 5 by the transmission controller and execute the other processes by the engine controller. In the case of using only the transmission controller, it may be determined whether or not the engine 1 is automatically stopped by determining whether or not an idle stop signal is input from the engine controller.

  Furthermore, in the above description, it is assumed that the three frictional engagement elements 31 to 33 are targeted as a plurality of frictional engagement elements, and that the first frictional engagement elements 31 to 33 are engaged at the first forward speed. In the neutral state, the two frictional engagement elements (specifically, the brake elements 32, 33) are maintained in the engagement state, and the remaining one frictional engagement element (the clutch element 31) is released, while in the second neutral state, all The case where the frictional engagement elements 31 to 33 are released has been described.

  However, the present invention is not limited to this setting, and when the three friction engagement elements are engaged at the first forward speed, the number of friction engagement elements maintained in the engagement state in the first neutral state is two, while the second neutral is The number of frictional engagement elements to be released in the state is two, and the remaining one frictional engagement element can be maintained in the engagement state regardless of the first and second neutral states. Furthermore, the number of frictional engagement elements maintained in the engaged state in the first neutral state is not limited to two, and may be only one. In this case, all the frictional engagement elements are released in the second neutral state.

  Thus, the number of frictional engagement elements that are engaged in the second neutral state may be smaller than the number of frictional engagement elements that are maintained in the engagement state in the first neutral state, for example, friction that is engaged at the forward first speed. When the number of fastening elements is two, one friction fastening element is fastened in the first neutral state, and both friction fastening elements are released in the second neutral state. And when there are a plurality of frictional engagement elements that are engaged in the first neutral state, not only all of them are released in the second neutral state, but as long as the number is smaller than that in the first neutral state, 1 One or more frictional engagement elements can also be maintained in the engaged state.

  Furthermore, the first neutral state can be selected while the drive source is being driven, in addition to the processes of S207 and 208 shown in FIG. That is, the first neutral state can be selected, for example, in at least one of the following cases.

  When the N range is selected during the driving of the driving source, when the P range is selected during the driving of the driving source, the P range or the N range is selected during the automatic stop of the driving source, and the second This is the case where the condition (transition condition) for selecting the neutral state is not satisfied or is canceled, or the travel range is selected during the automatic stop of the drive source.

  Further, the transition condition is not limited to the case where the shift range includes a predetermined condition other than the P range or the N range, and may be only that the P range is selected or only that the N range is selected. Good. Specifically, in the flowchart shown in FIG. 6, the process of S204 may be abolished and the process may advance to S205 when the determination made in S202 or S203 is established.

  The oil pump is not limited to the electric oil pump 51, but may be an oil pump driven by a motor or a motor generator constituting a drive source of the hybrid vehicle.

  Concepts other than those described in the claims, which can be derived from the above description, are shown below.

  1stly, it is the control apparatus of the automatic transmission mounted in the vehicle provided with a drive source and the oil pump which can supply a hydraulic oil with respect to the some fastening element with which an automatic transmission is equipped during the stop of a drive source. There are a shift range detection unit that detects the shift range of the automatic transmission, an automatic stop determination unit that determines whether or not an automatic stop is caused to automatically stop the drive source, and a neutral state of the automatic transmission. A first neutral state in which some of the fastening elements are fastened and the other fastening elements are released, and a smaller number of fastening elements than the first neutral state among the plurality of fastening elements are fastened, and the other fastening elements And a neutral state control unit configured to be selectively settable. The neutral state control unit sets the automatic transmission to the second neutral state when at least a condition including that the shift range is the park range or the neutral range and when the drive source is automatically stopped is established. If not, the first neutral state is assumed.

  Second, there is provided a control method for an automatic transmission mounted on a vehicle, comprising: a drive source; and an oil pump capable of supplying hydraulic oil to a plurality of fastening elements provided in the automatic transmission while the drive source is stopped. Yes, as a neutral state of the automatic transmission, a first neutral state in which some of the plurality of fastening elements are fastened and other fastening elements are released, and a number smaller than the first neutral state of the plurality of fastening elements And a second neutral state in which the other fastening elements are released, and the shift range of the automatic transmission is at least a park range or a neutral range, and a drive source is The automatic transmission is set to the second neutral state when a condition including being at the time of automatic stop to be automatically stopped is satisfied, and when the condition is not satisfied, the first neutral state To.

  Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various changes and modifications can be made within the scope of the matters described in the claims. Not too long.

P ... Vehicle drive system TM ... Automatic transmission 1 ... Engine 2 ... Torque converter 21 ... Pump impeller 22 ... Turbine runner 23 ... Lock-up clutch 3 ... Stepped transmission mechanism 31, 32 ... Clutch element 4 ... Final gear train 5 ... Differential 6 ... drive shaft 7 ... drive wheel 8 ... variator (main transmission)
9 ... Sub-transmission 91, 92 ... Clutch element 51 ... Oil pump 61 ... Hydraulic control circuit 101 ... Controller

Claims (8)

A driving source;
An automatic transmission connected to the drive source and having a plurality of fastening elements;
An oil pump capable of supplying hydraulic oil to the plurality of fastening elements while the drive source is stopped;
A vehicle control device comprising:
As the neutral state of the automatic transmission, a first neutral state in which a part of the plurality of fastening elements is fastened and a second neutral state in which the number of fastening elements is less than the first neutral state are selected. Has a controllable control unit,
The controller sets the automatic transmission to the second neutral state when a condition including that at least a park range is selected as a shift range of the automatic transmission is satisfied when the driving source is automatically stopped. To
Vehicle control device. A driving source;
An automatic transmission connected to the drive source and having a plurality of fastening elements;
An oil pump capable of supplying hydraulic oil to the plurality of fastening elements while the drive source is stopped;
A vehicle control device comprising:
As the neutral state of the automatic transmission, a first neutral state in which a part of the plurality of fastening elements is fastened and a second neutral state in which the number of fastening elements is less than the first neutral state are selected. Has a controllable control unit,
The control unit sets the automatic transmission to the second neutral state when a condition including that at least a neutral range is selected as a shift range of the automatic transmission is satisfied when the driving source is automatically stopped. To
Vehicle control device.   The vehicle control device according to claim 1, wherein the control unit further includes, as the condition, that a predetermined time has elapsed after the shift range is changed.   The vehicle control device according to any one of claims 1 to 3, wherein the control unit further includes, as the condition, that a seat belt is released.   The said control part is a vehicle control apparatus as described in any one of Claims 1-4 further including that a parking brake is in an ON state as said conditions. It further has a forward vehicle detection unit that detects the presence of the forward vehicle or the distance to the forward vehicle,
The vehicle control according to any one of claims 1 to 5, wherein the control unit further includes, as the condition, a vehicle ahead and a distance to the vehicle ahead is less than a predetermined distance. apparatus. A driving source;
An automatic transmission connected to the drive source and having a plurality of fastening elements;
An oil pump capable of supplying hydraulic oil to the plurality of fastening elements while the drive source is stopped;
A vehicle control method comprising:
As the neutral state of the automatic transmission, a first neutral state in which a part of the plurality of fastening elements is fastened and a second neutral state in which the number of fastening elements is less than the first neutral state are selected. Can be set automatically,
The automatic transmission is set to the second neutral state when a condition including that at least a park range is selected as a shift range of the automatic transmission is satisfied when the driving source is automatically stopped.
Vehicle control method. A driving source;
An automatic transmission connected to the drive source and having a plurality of fastening elements;
An oil pump capable of supplying hydraulic oil to the plurality of fastening elements while the drive source is stopped;
A vehicle control method comprising:
As the neutral state of the automatic transmission, a first neutral state in which a part of the plurality of fastening elements is fastened and a second neutral state in which the number of fastening elements is less than the first neutral state are selected. Can be set automatically,
The automatic transmission is set to the second neutral state when a condition including that the neutral state is selected as at least the shift range of the automatic transmission is satisfied when the driving source is automatically stopped.
Vehicle control method.

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