JP4999874B2 - Control device for automatic transmission - Google Patents

Description

  The present invention relates to a control device for an automatic transmission provided with a plurality of power transmission systems having a clutch for controlling disconnection / connection of power from a drive source and a transmission mechanism coupled to the clutch in a state where power can be transmitted.

  Conventionally, as an automatic transmission mounted on a vehicle, for example, an automatic transmission described in Patent Document 1 has been proposed. This automatic transmission is a so-called dual clutch type automatic transmission and includes two power transmission systems. The first power transmission system includes a first clutch and a gear train that is connected in a state capable of transmitting power to the first clutch and that has an odd number of gears (first gear, third gear, and fifth gear). And a first speed change mechanism. The second power transmission system is coupled to the second clutch and the second clutch in a state where power can be transmitted to the second clutch, and gears of even-numbered gear stages (second speed stage, fourth speed stage and sixth speed stage). And a second speed change mechanism having a row. For example, when the vehicle is driven with the first gear set, the first transmission mechanism is set to the first gear and the first clutch is engaged so that the power from the engine serving as the drive source is set. Is transmitted to the drive wheels via the first power transmission system, and the vehicle travels. When the gear stage is the first speed stage, the second clutch of the second power transmission system is in a released state, and power from the engine is not transmitted to the second power transmission system.

  By the way, in the control apparatus for an automatic transmission described in Patent Document 1, preshift control is executed in accordance with the traveling state of the vehicle. For example, when the vehicle is accelerating, there is a high possibility that the shift stage of the automatic transmission is upshifted. Therefore, the control device for the automatic transmission specifies the current gear position (for example, the third gear) of the automatic transmission, and determines the first gear position in the second power transmission system to which power is not transmitted at the first time. Pre-shift control is executed so as to prepare at a gear position (in this case, the fourth speed) higher than the gear position (for example, the third speed) set in the power transmission system. That is, during the acceleration of the vehicle, the preshift control is executed on the upshift side. Therefore, when actually shifting up the shift stage of the automatic transmission, the power from the engine is transmitted to the second power transmission only by disengaging the first clutch and engaging the second clutch. It is transmitted to the drive wheel through the system. Therefore, it is possible to provide a quick upshift as compared with the case where the preshift control is not executed or the case where the preshift control is executed on the downshift side.

Japanese Patent Laid-Open No. 2007-232047

  However, for example, when the driver operates the accelerator pedal, the shift stage of the automatic transmission is not necessarily upshifted. For example, when the vehicle travels on an uphill road, the acceleration of the vehicle may be reduced due to insufficient power transmitted to the drive wheels, even though the accelerator pedal is operated. In such a case, the amount of operation of the accelerator pedal is increased by the driver of the vehicle, and the shift stage of the automatic transmission is downshifted to increase the power transmitted to the drive wheels. Even in such a situation, when the pre-shift control is executed on the upshift side because the accelerator pedal is being operated, first, the gear position in the second power transmission system is set in the first power transmission system. After preparation is made at a speed lower than the speed, it is necessary to disengage the first clutch and to engage the second clutch. Therefore, when the preshift control corresponding to the road on which the vehicle is traveling is not executed, there is a problem that it takes time until the shift change of the automatic transmission is completed after the shift change is requested.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a control device for an automatic transmission capable of executing appropriate preshift control according to the traveling state of a vehicle traveling on an uphill / downhill road. It is in.

  In order to achieve the above object, the invention according to claim 1 relating to a control device for an automatic transmission is provided with a clutch for controlling the connection / disconnection of power from a driving source and a state in which power can be transmitted to the clutch. The power transmission system includes two power transmission systems each having a transmission mechanism that is configured to transmit power from the drive source to any one of the power transmission systems when the vehicle travels. A control device for an automatic transmission that executes control for bringing one clutch included in the engagement state into an engaged state and bringing the other clutch included in the other power transmission system into a released state, wherein the vehicle is traveling on an uphill / downhill road An uphill / downhill determination means for determining whether or not there is a decrease in acceleration of the vehicle during operation of the accelerator pedal of the vehicle when the up / downhill road determination means determines that the vehicle is traveling on the uphill road Acceleration request detection means for detecting an increase in the amount of operation of the accelerator pedal after detection of a decrease in acceleration of the vehicle, and a decrease in acceleration of the vehicle or the acceleration of the vehicle during operation of the accelerator pedal by the acceleration request detection means When an increase in the amount of operation of the accelerator pedal is detected after detection of a decrease in engine power, power is transmitted from the drive source to the shift stage of the other power transmission system to which power is not transmitted from the drive source. And a pre-shift control means for executing pre-shift control for preparing at a speed lower than the speed selected by one of the power transmission systems.

  According to the above configuration, when the vehicle is traveling on an uphill road, a decrease in the acceleration of the vehicle during the operation of the accelerator pedal of the vehicle or an increase in the amount of operation of the accelerator pedal after detecting a decrease in the acceleration of the vehicle is detected. When this is done, the driver is likely to request acceleration or the driver requests acceleration. Therefore, since there is a high possibility that a downshift will be executed after that, the shift stage of the other power transmission system to which power from the drive source is not transmitted is changed to the shift stage of one power transmission system to which power is transmitted. Pre-shift control is executed to prepare at a lower speed gear stage (that is, the gear stage currently selected as the automatic transmission). Therefore, it is possible to execute appropriate preshift control according to the traveling state of the vehicle traveling on the uphill / downhill road.

  According to a second aspect of the present invention, in the automatic transmission control device according to the first aspect, when the uphill / downhill determination unit determines that the vehicle is traveling on the downhill road, a deceleration request for the vehicle is made. The pre-shift control means further includes a shift stage of the other power transmission system when the deceleration request determination means determines that there is a vehicle deceleration request. The gist of the present invention is to execute pre-shift control that prepares at a speed lower than the speed selected by the one power transmission system.

  According to the above configuration, when it is determined that there is a request for deceleration of the vehicle when the vehicle is traveling on a downhill road, there is a high possibility that the driver has an intention to decelerate the vehicle. Therefore, the speed stage of the other power transmission system to which power from the drive source is not transmitted is changed to the speed stage of one power transmission system to which power is transmitted (that is, the speed stage currently selected as an automatic transmission). Pre-shift control is performed to prepare at a lower gear position. Therefore, when traveling on a downhill road, appropriate preshift control is executed in accordance with the traveling state of the vehicle.

  According to a third aspect of the present invention, in the control device for an automatic transmission according to the second aspect, the pre-shift control unit is configured to detect the other when the deceleration request determination unit determines that there is no vehicle deceleration request. The gist of the present invention is to execute pre-shift control in which the gear stage of the power transmission system is prepared at a gear stage on the higher speed side than the gear stage selected by the one power transmission system.

  According to the above configuration, when it is determined that there is no request for deceleration of the vehicle when the vehicle is traveling on a downhill road, there is a high possibility that an upshift will be executed. For this reason, pre-shift control is executed in which the gear stage of the other power transmission system to which power from the drive source is not transmitted is prepared at a gear speed side higher than the gear stage of one power transmission system to which power is transmitted. The Therefore, when traveling on a downhill road, appropriate preshift control is executed in accordance with the traveling state of the vehicle.

  According to a fourth aspect of the present invention, in the control apparatus for an automatic transmission according to any one of the first to third aspects, a gradient acquisition unit that acquires a gradient of a road surface on which the vehicle travels, A vehicle body speed calculating means for calculating the vehicle body speed; and an opening degree obtaining means for obtaining the opening degree of the accelerator pedal of the vehicle. The start timing of the preshift control is a gradient obtained by the gradient obtaining means, The gist is set by at least one of the vehicle body speed calculated by the vehicle body speed calculating means and the opening degree acquired by the opening degree acquiring means.

  According to the above configuration, when the vehicle travels on an uphill / downhill road, the start timing of the preshift control is set by at least one of the road surface gradient, the vehicle body speed, and the accelerator pedal opening. Therefore, when the shift is actually changed, the pre-shift control is surely executed, so that it is possible to contribute to a quick shift change of the automatic transmission.

The block diagram of the vehicle carrying the automatic transmission in 1st Embodiment. The skeleton figure which shows the automatic transmission of 1st Embodiment. The flowchart explaining a preshift determination processing routine. The flowchart explaining a slope determination process routine. The flowchart explaining the acceleration request | requirement determination processing routine in 1st Embodiment. A map for setting an uphill road threshold and a downhill road threshold according to the vehicle speed. The flowchart explaining a part of acceleration request determination processing routine in 2nd Embodiment.

(First embodiment)
A first embodiment in which the present invention is embodied in a control device for an automatic transmission mounted on a vehicle will be described with reference to FIGS.

  As shown in FIG. 1, the vehicle of this embodiment has a plurality of (four in this embodiment) wheels (right front wheel FR, left front wheel FL, right rear wheel RR, and left rear wheel RL) that are in contact with the road surface during traveling. Of these, the front wheels FR and FL function as drive wheels, and the rear wheels RR and RL function as driven wheels. Such a vehicle is provided with an engine 12 as a drive source that generates power (torque) according to the amount of depression of the accelerator pedal 11 by the driver. The power generated by the engine 12 is supplied to the automatic transmission 13 or the like. To the front wheels FR and FL. The vehicle of the present embodiment is provided with an electronic control unit (hereinafter referred to as “engine ECU”) 14 that controls the driving mode of the engine 12 in accordance with the operating mode of the accelerator pedal 11 by the driver, and the engine ECU 14. , An accelerator sensor SE1 for detecting the opening of the accelerator pedal 11 (also referred to as “accelerator opening”) is electrically connected. Then, the engine ECU 14 calculates the accelerator opening based on the detection signal from the accelerator sensor SE1, and transmits information related to the calculation result to the ECU 40 for the automatic transmission 13 described later.

Next, the automatic transmission 13 will be described with reference to FIG.
As shown in FIG. 2, the automatic transmission 13 according to the present embodiment is a so-called dual clutch type transmission having seven forward speeds and one reverse speed. Such an automatic transmission 13 includes a plurality (two in this embodiment) of clutches C1 and C2, a first input shaft 15 coupled to the first clutch C1, and a second clutch coupled to the second clutch C2. An input shaft 16, a first gear transmission mechanism 17 for odd-numbered stages (first speed, third speed, fifth speed and seventh speed), an even speed (second speed, fourth speed, sixth speed) and A second gear transmission mechanism 18 for the reverse gear and an output shaft 19 that can rotate coaxially with the input shafts 15 and 16 are provided. Power is transmitted from the output shaft 19 to the front wheels FR and FL via a differential (not shown).

  The first input shaft 15 is a rod-shaped member extending from the first clutch C1 in a predetermined direction (left-right direction in FIG. 2), and the first clutch C1 is engaged by driving the clutch actuator 20. When it becomes, it rotates centering on the rotating shaft line (not shown) extended along a predetermined direction. The second input shaft 16 is a cylindrical member extending along a predetermined direction from the second clutch C2, and the first input shaft 15 has a first clutch C1 in the second input shaft 16. The side part is accommodated. The second input shaft 16 rotates coaxially with the first input shaft 15 when the second clutch C <b> 2 is engaged by driving the clutch actuator 20. The engagement of the clutches C1 and C2 refers to the engagement between the input side and the output side of the clutches C1 and C2. The release of the clutches C1 and C2 refers to the input side and the output side of the clutches C1 and C2. Means that power transmission becomes impossible due to separation.

  The first gear transmission mechanism 17 is held in a state of being relatively rotatable with respect to the first input shaft 15, and is arranged in order along a predetermined direction, and a first gear transmission gear 211, a seventh gear transmission gear 217, 3 A speed change gear 213 and a fifth speed change gear 215 held in an integrally rotatable state with the output shaft 19 are provided. Further, the first gear transmission mechanism 17 is fixed to a counter shaft 22 arranged in parallel to the input shafts 15 and 16 and the output shaft 19 so as to be integrally rotatable, and each of the transmission gears 211, odd-numbered gears 211, A plurality of (four in this embodiment) counter gears 231, 233, 235, and 237 that individually mesh with 213, 215, and 217 are provided.

  The first gear transmission mechanism 17 includes a first gear selection mechanism 25 that selects the first-speed gear 211 or the seventh-speed gear 217, and the third-speed gear 213 or the fifth gear. A second gear selection mechanism 26 that selects the transmission gear 215 is provided. Each of the gear selection mechanisms 25 and 26 is provided with a cylindrical sleeve 24 that can rotate integrally with the first input shaft 15 on the outer peripheral side of the first input shaft 15. These sleeves 24 are arranged between a transmission gear (for example, a first-speed transmission gear 211) positioned on one side in a predetermined direction and a transmission gear (for example, a seventh-speed transmission gear 217) positioned on the other side in a predetermined direction. Each can be moved.

  Each of the gear selection mechanisms 25 and 26 is provided with a drive unit 27 for moving the sleeve 24 along a predetermined direction. The drive unit 27 is driven by the selection actuators 28A and 28B. Each is given power. Then, by driving the drive unit 27, the sleeve 24 is engaged with a transmission gear located on one side (left side in FIG. 2) in a predetermined direction or on the other side (right side in FIG. 2) in the predetermined direction. When arranged at the second engagement position where the transmission gear is positioned, the transmission gear engaged with the sleeve 24 can rotate integrally with the first input shaft 15. For example, when the sleeve 24 of the second gear selection mechanism 26 is disposed at the second engagement position, the power from the first input shaft 15 is transmitted to the fifth speed gear 215 via the sleeve 24. The On the other hand, when the sleeve 24 is disposed at a neutral position between the two transmission gears located on both sides in the predetermined direction, power is transmitted to the transmission gears 211, 213, 215, and 217 via the first input shaft 15. Not.

  The second gear transmission mechanism 18 is held in a state of being relatively rotatable with respect to the second input shaft 16, and each of the even-numbered transmission gears (second-speed transmission gear 212, fourth-speed transmission gear) arranged in order along a predetermined direction. A step-change gear 214, a sixth-speed gear 216), and a reverse gear 21R. The second gear transmission mechanism 18 is fixed to the counter shaft 22 so as to be integrally rotatable, and a plurality of (four in this embodiment) counters individually corresponding to the transmission gears 212, 214, 216, and 21R. Gears 232, 234, 236 and 23R are provided. The counter gears 232, 234, and 236 for the even-numbered forward gears mesh with the corresponding transmission gears 212, 214, and 216, respectively. Further, an idler gear 29 that meshes with the reverse gear 21R and the counter gear 23R is provided between the reverse gear 21R and the counter gear 23R. The idler gear 29 is connected to the reverse gear 21R from the reverse gear 21R. Power can be transmitted to the counter gear 23R.

  Further, the second gear transmission mechanism 18 includes a third gear selection mechanism 31 that selects the second gear transmission gear 212 or the fourth gear transmission gear 214, a sixth gear transmission gear 216, or the reverse gear transmission. A fourth shift speed selection mechanism 32 for selecting the gear 21R is provided. Each of these gear selection mechanisms 31 and 32 is similar to the first and second gear selection mechanisms 25 and 26 described above, and includes a sleeve 24 disposed on the outer peripheral side of the second input shaft 16 and selection actuators 28C and 28D. And a drive unit 27 to which the drive force is applied. That is, in the third and fourth shift speed selection mechanisms 31 and 32, the sleeves 24 are respectively disposed at any one of the first engagement position, the second engagement position, and the neutral position by the drive of the drive unit 27. The The transmission gear (for example, the second speed transmission gear 212) engaged with the sleeve 24 can rotate integrally with the second input shaft 16.

  In such an automatic transmission 13, when the vehicle is driven with the gear set to the first gear, the sleeve 24 of the first gear select mechanism 25 is moved to the first engagement position by driving the actuators 28A and 28B for selection. And the sleeve 24 of the second gear selection mechanism 26 is disposed at the neutral position. Subsequently, by driving the clutch actuator 20, the first clutch (one clutch) C1 is brought into an engaged state and the second clutch (the other clutch) C2 is brought into a released state. Then, the power from the engine 12 is transmitted from the first clutch C1, the first input shaft 15, the first speed transmission gear 211, the counter gear 231, the counter shaft 22, the counter gear 235, the fifth speed transmission gear 215, and the output. The vehicle travels to the front wheels FR and FL via the shaft 19 and the like. Therefore, in this embodiment, the first clutch C1, the first input shaft 15 and the first gear transmission mechanism 17 constitute a first power transmission system.

  Further, when the vehicle is driven with the gear position of the automatic transmission 13 set to the second gear, the sleeve 24 of the third gear selection mechanism 31 is engaged with the first engagement by driving the selection actuators 28C and 28D. The sleeve 24 of the fourth gear selection mechanism 32 is disposed at the neutral position while being disposed at the position and engaged with the transmission gear 212 for the second gear. Subsequently, by driving the clutch actuator 20, the second clutch (one clutch) C2 is brought into an engaged state, and the first clutch (the other clutch) C1 is brought into a released state. Then, the power from the engine 12 is transmitted from the second clutch C2, the second input shaft 16, the second speed transmission gear 212, the counter gear 232, the counter shaft 22, the counter gear 235, the fifth speed transmission gear 215, and the output. The vehicle travels to the front wheels FR and FL via the shaft 19 and the like. Therefore, in the present embodiment, the second clutch C2, the second input shaft 16, and the second gear transmission mechanism 18 constitute a second power transmission system provided in parallel with the first power transmission system.

Next, an electronic control unit (hereinafter referred to as “ECU”) 40 as a control unit that controls the driving of the automatic transmission 13 will be described below with reference to FIGS. 1 and 2.
As shown in FIGS. 1 and 2, the ECU 40 interface includes wheel speed sensors SE2 and SE3 for detecting the wheel speeds of the rear wheels RR and RL, and temperature sensors for detecting the temperatures of the clutches C1 and C2. SE4, SE5, a vehicle body speed sensor SE6 for detecting the vehicle body speed of the vehicle, and a brake switch SW1 for detecting whether a brake pedal (not shown) of the vehicle is operated are electrically connected. Further, the clutch actuator 20 and the selection actuators 28A to 28D are electrically connected to the interface of the ECU 40. Further, the ECU 40 receives various types of information related to the accelerator opening degree transmitted from the engine ECU 14.

  The ECU 40 has a digital computer constructed from a CPU 41, a ROM 42, a RAM 43, and the like. The ROM 42 has various control programs (such as preshift determination processing described later) for driving the actuators 20, 28A to 28D to control the automatic transmission 13, and various threshold values (vehicle speed threshold value, downhill road threshold value described later). , Climbing slope threshold, etc.) are stored. Further, the RAM 43 stores various information (vehicle speed, actual acceleration, target acceleration, acceleration difference, pre-shift gear stage, uphill road flag, downhill road flag, which will be described later) when the ignition switch (not shown) of the vehicle is turned on. , An acceleration request flag, a deceleration request flag, etc.) are stored.

  Next, the preshift determination processing routine executed by the ECU 40 of the present embodiment will be described based on the flowcharts shown in FIGS. This pre-shift determination process routine is a process that is executed at predetermined intervals (for example, every 0.01 seconds) while an ignition switch (not shown) of the vehicle is “ON”.

  In the pre-shift determination process routine, the ECU 40 executes a slope determination process (described in detail in FIG. 4) for determining whether or not the road surface on which the vehicle travels is a slope (step S10). In this slope determination process, the uphill road flag FLGu and the downhill road flag FLGd are set. The uphill road flag FLGu is a flag that is set to “ON” when the road surface on which the vehicle is traveling is an uphill road, and is set to “OFF” when the road surface is not an uphill road. The downhill road flag FLGd is a flag that is set to “ON” when the road surface on which the vehicle is traveling is a downhill road, and is set to “OFF” when the road surface is not a downhill road.

  Subsequently, the ECU 40 sets, as a normal preshift gear position, a preshift gear position according to the traveling state of the vehicle when it is assumed that the road surface on which the vehicle travels is a flat surface (that is, a road surface that is not a slope) (step S11). . The pre-shift gear stage is a gear stage that is prepared so as to be able to rotate integrally with the input shaft in a gear transmission mechanism that is not currently transmitting power from the engine 12. For example, when the ECU 40 receives information indicating that the driver is operating the accelerator pedal 11 from the engine ECU 14, the ECU 40 has a gear position that is one speed higher than the currently set gear position (for example, the fourth gear). (In this case, the fifth gear) is selected as the normal preshift gear. Further, when the ECU 40 detects that the driver is operating the brake pedal based on the detection signal from the brake switch SW1, the ECU 40 is one speed lower than the currently set speed (for example, the fourth speed). Is selected as the normal pre-shift gear stage.

  Then, the ECU 40 determines whether or not the uphill road flag FLGu is “ON” (step S12). If the determination result is affirmative (FLGu = ON), the ECU 40 performs an acceleration request determination process (described in detail in FIG. 5) for determining whether or not there is a high possibility that the driver will request an acceleration. Execute (Step S13). In this acceleration request determination process, if it is determined that the driver is likely to request acceleration, the acceleration request flag FLGa is set to “ON”, and it is determined that the driver is unlikely to request acceleration. If so, the acceleration request flag FLGa is set to “OFF”. Subsequently, the ECU 40 determines whether or not the acceleration request flag FLGa is “ON” (step S14). If this determination result is affirmative (FLGa = ON), the ECU 40 sets the preshift gear position to a gear position that is one speed lower than the currently selected gear position in the automatic transmission 13 (step S15). ), The process proceeds to step S20 to be described later. On the other hand, if the determination result in step S14 is negative (FLGa = OFF), the ECU 40 sets the preshift gear to the normal preshift gear set in step S11 (step S16), and the process will be described later. The process proceeds to S20.

  On the other hand, when the determination result of step S12 is negative (FLGu = OFF), the ECU 40 determines whether or not the downhill road flag FLGd is “ON” (step S17). If this determination is negative (FLGd = OFF), the ECU 40 proceeds to step S16 described above. On the other hand, if the determination result of step S17 is affirmative (FLGd = ON), the ECU 40 executes a deceleration request determination process for determining whether or not there is a deceleration request (step S18-1). That is, the ECU 40 determines whether or not the accelerator pedal 11 is being operated based on various information received from the engine ECU 14. If it is determined that the accelerator pedal 11 is not operated, the ECU 40 determines that the driver has the intention to decelerate the vehicle, sets the deceleration request flag FLGb to “ON”, and ends the deceleration request determination process. To do. On the other hand, when it is determined that there is a possibility that the accelerator pedal 11 is being operated, the ECU 40 determines whether or not a brake pedal (not shown) is being operated. When the brake switch SW1 is “ON”, the ECU 40 determines that the driver intends to decelerate the vehicle, sets the deceleration request flag FLGb to “ON”, and ends the deceleration request determination process. On the other hand, when the brake switch SW1 is “OFF”, the ECU 40 determines that the driver does not intend to decelerate the vehicle, sets the deceleration request flag FLGb to “OFF”, and ends the deceleration request determination process. The deceleration request flag FLGb is set to “ON” when it is determined that there is a deceleration request from the driver, and is set to “OFF” when it is determined that there is no deceleration request. It is.

  Subsequently, the ECU 40 determines whether or not the deceleration request flag FLGb is “ON” (step S18-2). If the determination result is affirmative (FLGb = ON), the ECU 40 proceeds to step S15 described above. On the other hand, if the determination result in step S18-2 is negative (FLGb = OFF), the ECU 40 determines that the accelerator pedal 11 is being operated, and the pre-shift gear stage is selected at the present time in the automatic transmission 13. The speed is set to a speed higher by one speed than the speed (step S19), and the process proceeds to the next step S20. Therefore, in this embodiment, the ECU 40 also functions as a deceleration request determination unit.

  In step S20, the ECU 40 determines whether each step S15, S16. Pre-shift control is executed based on the pre-shift gear set in any step of S19. Note that preshift control when the preshift gear stage is the third speed stage in the state where the speed stage currently selected in the automatic transmission 13 is the fourth speed stage will be described. That is, the ECU 40 drives the selection actuator 28B to move the sleeve 24 of the second gear selection mechanism 26 to the first engagement position. Then, the third-speed gear 213 can rotate integrally with the first input shaft 15 via the sleeve 24. Therefore, in the present embodiment, the ECU 40 selects a gear stage of another power transmission system different from the one power transmission system to which the power from the engine 12 is currently transmitted by the gear transmission mechanism of the one power transmission system. It also functions as a pre-shift control means for executing pre-shift control so as to be prepared at a shift speed lower than the shift speed. Note that the preshift control that is prepared in the automatic transmission 13 at a speed lower than the currently selected speed is also referred to as “downshift preshift control”, and the preshift that is prepared at the higher speed. The control is also referred to as “preshift control to the upshift side”.

Thereafter, the ECU 40 once ends the preshift determination processing routine.
Next, the slope judgment process (slope judgment routine) in step S10 will be described based on the flowchart shown in FIG.

  In the slope determination process routine, the ECU 40 calculates the vehicle body speed VS of the vehicle based on the detection signal from the vehicle body speed sensor SE6 (step S30). Therefore, in the present embodiment, the ECU 40 also functions as a vehicle body speed calculation unit. Subsequently, the ECU 40 calculates the actual acceleration DVSr of the vehicle by differentiating the vehicle body speed VS calculated in step S30 (step S31). Then, the ECU 40 calculates the target acceleration DVSt of the vehicle (step S32). Specifically, the ECU 40 acquires the accelerator opening from the information received from the engine ECU 14, acquires the gear stage currently selected in the automatic transmission 13, and outputs the output shaft from the acquired accelerator opening and the gear stage. 19 rotation speeds are estimated. Then, the ECU 40 calculates the target acceleration DVSt of the vehicle based on the estimated rotation speed of the output shaft 19. The target acceleration DVSt is calculated as a speed close to the actual acceleration of the vehicle when traveling on a flat road surface.

  Subsequently, the ECU 40 calculates an acceleration difference DVSdiff by subtracting the actual acceleration DVSr calculated in step S31 from the target acceleration DVSt calculated in step S32 (step S33). Here, when the vehicle travels on a flat road surface, the acceleration difference DVSdiff is a value close to “0 (zero)”. However, when the vehicle travels on a slope, the absolute value of the acceleration difference DVSdiff is significantly different from “0 (zero)”. Further, the absolute value of the acceleration difference DVSdiff tends to increase as the slope of the slope increases. Therefore, the acceleration difference DVSdiff is calculated as a value corresponding to the slope of the road surface on which the vehicle travels. Therefore, in the present embodiment, the ECU 40 also functions as a gradient acquisition unit that acquires the gradient (acceleration difference DVSdiff) of the road surface on which the vehicle travels.

  Then, the ECU 40 determines whether or not the vehicle body speed VS calculated in step S30 exceeds a preset vehicle body speed threshold VSth (for example, 10 km / h (10 kilometers per hour)) (step S34). The vehicle body speed threshold value VSth is a reference value for determining whether or not the vehicle is stopped or is likely to stop, and is set in advance by experiments or simulations. If the determination result in step S34 is affirmative (VS> VSth), the ECU 40 determines whether or not the acceleration difference DVSdiff calculated in step S33 is less than or equal to a preset downhill threshold DVSddiffth (step S35). ). This downhill road threshold value DVSddiffth is a reference value for determining whether or not the vehicle is traveling on a downhill road, and is set in advance by experiments or simulations. When the vehicle travels on a downhill road, the actual acceleration DVSr becomes larger than the target acceleration DVSt, so the acceleration difference DVSdiff becomes a negative value. Therefore, the descending slope threshold DVSddiffth is set as a negative value.

  When the determination result in step S35 is affirmative (DVSdiff ≦ DVSddiffth), the ECU 40 sets the uphill road flag FLGu to “OFF” and sets the downhill road flag FLGd to “ON” because the vehicle is traveling on the downhill road. (Step S36), and the slope determination processing routine ends. On the other hand, if the determination result in step S35 is negative (DVSdiff> DVSddiffth), the ECU 40 determines whether or not the acceleration difference DVSdiff calculated in step S33 is greater than or equal to a preset uphill threshold DVSudiffth ( Step S37). This uphill road threshold DVSudiffth is a reference value for determining whether or not the vehicle is traveling on an uphill road, and is set in advance by experiments or simulations. When the vehicle travels on an uphill road, the actual acceleration DVSr is smaller than the target acceleration DVSt, so that the acceleration difference DVSdiff is a positive value. For this reason, the uphill road threshold DVSudiffth is set to a positive value.

  When the determination result in step S37 is affirmative (DVSdiff ≧ DVSudiffth), the ECU 40 sets the uphill road flag FLGu to “ON” and sets the downhill road flag FLGd to “OFF” because the vehicle is traveling on the uphill road. ”(Step S38), and the slope determination processing routine is terminated. On the other hand, if the determination result in step S37 is negative (DVSdiff <DVSudiffth), the ECU 40 determines that the road surface on which the vehicle is traveling is neither an uphill road nor a downhill road, and sets both the uphill road flag FLGu and the downhill road flag FLGd. “OFF” is set (step S39), and the slope determination processing routine is terminated. Therefore, in this embodiment, ECU40 functions also as an up-and-down slope determination means.

On the other hand, when the determination result of step S34 is negative (VS ≦ VSth), the ECU 40 proceeds to step S39 described above.
Next, the acceleration request determination process (acceleration request determination process routine) in step S13 will be described based on the flowchart shown in FIG.

  In the acceleration request determination processing routine, the ECU 40 determines whether or not the accelerator pedal 11 is being operated by the driver based on various information received from the engine ECU 14 (step S40). When the determination result is affirmative determination (accelerator pedal 11 is being operated), the ECU 40 determines whether or not the actual acceleration DVSr calculated in step S31 is less than a preset acceleration request determination threshold value DVSth ( Step S41). The acceleration request determination threshold value DVSth is a reference value for determining whether or not the vehicle is accelerating, and is set in advance by experiments or simulations. If the determination result in step S41 is affirmative (DVSr <DVSth), the ECU 40 determines that the acceleration of the vehicle may be decreasing despite the accelerator pedal 11 being operated, and requests acceleration. The flag FLGa is set to “ON” (step S42), and the acceleration request determination processing routine is terminated. Therefore, in this embodiment, ECU40 functions also as an acceleration request | requirement detection means.

  On the other hand, if either one of the determination results of steps S40 and S41 is a negative determination (the accelerator pedal 11 is not operated or DVSr ≧ DVSth), the ECU 40 has no intention to accelerate the vehicle. Alternatively, it is determined that the power transmitted to the front wheels FR and FL is sufficient at the present time. Then, the ECU 40 sets the acceleration request flag FLGa to “OFF” (step S43), and ends the acceleration request determination processing routine.

Therefore, in this embodiment, the following effects can be obtained.
(1) When the vehicle is traveling on an uphill road, if the acceleration of the vehicle tends to decrease in a state where the accelerator pedal 11 of the vehicle is operated by the driver, the driver may request acceleration. high. That is, there is a high possibility that a downshift will be performed after that. Therefore, preshift control to the downshift side is executed. Therefore, it is possible to execute appropriate preshift control according to the traveling state of the vehicle traveling on the uphill road.

  (2) When the vehicle is traveling on a downhill road, when the accelerator pedal 11 is not operated by the driver or when the brake pedal is being operated, the driver has an intention to decelerate the vehicle. Probability is high. Therefore, preshift control to the downshift side is executed. Therefore, when traveling on a downhill road, it is possible to execute appropriate preshift control according to the traveling state of the vehicle.

  (3) On the other hand, when the vehicle is traveling on a downhill road, when the accelerator pedal 11 is operated by the driver, there is a high possibility that an upshift will be executed, so preshift control is executed on the upshift side. Is done. Therefore, when traveling on a downhill road, it is possible to execute appropriate preshift control according to the traveling state of the vehicle.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. The second embodiment is different from the first embodiment in that the uphill road threshold DVSudiffth and the downhill road threshold DVSddiffth are changed according to the vehicle body speed VS. Therefore, in the following description, parts different from those of the first embodiment will be mainly described, and the same or corresponding member configurations as those of the first embodiment are denoted by the same reference numerals, and redundant description will be omitted. Shall.

  A map shown in FIG. 6 is stored in the ROM 42 of the ECU 40 of the present embodiment. This map is a map for setting the uphill road threshold DVSudiffth and the downhill road threshold DVSddiffth according to the vehicle body speed VS of the vehicle. That is, as shown in FIG. 6, when the vehicle body speed VS is less than the first speed VS1, the uphill road threshold DVSudiffth is set to a positive first threshold DVSdiff1, and the downhill road threshold DVSddiffth is a negative value. Is set to the second threshold value DVSdiff2. Further, when the vehicle body speed VS is equal to or higher than the first speed VS1 and lower than the second speed VS2 that is higher than the first speed VS1, the uphill road threshold DVSudiffth is increased as the vehicle body speed VS increases. On the other hand, the descending slope threshold value DVSddiffth is gradually set to a smaller value as the vehicle body speed VS becomes higher. When the vehicle body speed VS is equal to or higher than the second speed VS2, the uphill road threshold value DVSudiffth is set to a third threshold value DVSdiff3 that is greater than the first threshold value DVSdiff1 and is a positive value. The threshold value DVSddiffth is smaller than the second threshold value DVSdiff2 and is set to a negative fourth threshold value DVSdiff4.

  As a result, when the vehicle travels on the uphill road, the uphill road threshold DVSudiffth is changed according to the vehicle body speed VS, so the timing at which the uphill road flag FLGu is set to “ON” is changed. That is, when the vehicle body speed VS of the vehicle is low, the deceleration rate due to traveling on the uphill road tends to be higher than when the vehicle body speed VS is high. Therefore, in the present embodiment, when the vehicle body speed VS is low, the uphill road flag FLGu is set to “ON” at an earlier timing than when the vehicle body speed VS is high, and the preshift to the downshift side is performed. Control is started at an early timing.

  Similarly, when the vehicle travels on a downhill road, the downhill road threshold DVSddiffth is changed according to the vehicle body speed VS, so the timing at which the downhill road flag FLGd is set to “ON” is changed. That is, when the vehicle body speed VS is low, the vehicle tends to be upshifted at an earlier timing than when the vehicle body speed VS is high. Therefore, in this embodiment, when the vehicle body speed VS is low, the downhill flag FLGd is set to “ON” at an earlier timing than when the vehicle body speed VS is high, and the preshift to the upshift side is performed. Control is started at an early timing.

Therefore, in this embodiment, in addition to the effects equivalent to the effects (1) to (3) in the first embodiment, the following effects can be further obtained.
(4) In the present embodiment, when the vehicle travels on a slope, pre-shift control is executed at an appropriate timing according to the vehicle body speed VS of the vehicle at that time. Therefore, when the actual shift change is requested from the ECU 40, the preshift control to the upshift (or downshift) side when the preshift control is not executed or the downshift (or upshift) is requested. Can be prevented from being executed. Therefore, when an actual shift change is requested from the ECU 40, it is possible to contribute to a quick shift change of the automatic transmission 13.

Each embodiment may be changed to another embodiment as described below.
In the second embodiment, the uphill road threshold DVSudiffth and the downhill road threshold DVSddiffth may be set according to the accelerator opening of the accelerator pedal 11.

  In the second embodiment, the method of changing the start timing of the preshift control to the downshift side in accordance with the vehicle body speed VS may be the following method that does not change the uphill road threshold DVSudiffth and the downhill road threshold DVSddiffth. For example, when the determination result in step S37 is affirmative, the uphill road flag FLGu may be set to “ON” when the vehicle body speed VS of the vehicle becomes less than a predetermined speed. However, the predetermined speed is desirably a value larger than the vehicle body speed threshold VSth. Even if comprised in this way, the effect equivalent to 2nd Embodiment can be acquired.

  -In each embodiment, you may change an acceleration request determination process as shown below. That is, as shown in FIG. 7, when the determination result in step S40 is affirmative, the ECU 40 determines whether or not an acceleration request flag FLGa is “ON” (step S401). When this determination result is a negative determination (FLGa = OFF), the ECU 40 proceeds to the process at step S41. On the other hand, if the determination result in step S401 is affirmative (FLGa = ON), the ECU 40 acquires the accelerator opening AR based on various information received from the engine ECU 14, differentiates the accelerator opening AR, A change amount ARh is acquired (step S402). In this respect, the ECU 40 also functions as an opening degree obtaining unit. Subsequently, the ECU 40 determines whether or not the change amount ARh of the accelerator opening AR acquired in step S402 exceeds a predetermined amount ARhth (for example, 0 (zero)) set in advance (step S403). That is, in step S403, it is determined whether or not the amount of operation of the accelerator pedal 11 by the driver has increased in a state where the vehicle tends to decelerate. If the determination result in step S403 is affirmative (ARh> ARhth), the ECU 40 sets the accelerator flag FLGh to “ON” (step S404), and ends the acceleration request determination processing routine. On the other hand, if the determination result in step S403 is negative (ARh ≦ ARhth), the ECU 40 sets the accelerator flag FLGh to “OFF” (step S405), and ends the acceleration request determination processing routine.

  Thereafter, the ECU 40 determines whether or not both the acceleration request flag FLGa and the accelerator flag FLGh are “ON” (step S14). The ECU 40 proceeds to step S15 when both the flags FLGa and FLGh are “ON”, and performs the process when at least one of the flags FLGa and FLGh is “OFF”. Step S16 is performed.

  In this other embodiment, when the vehicle tends to decelerate due to traveling on an uphill road, a downshift request is input to the ECU 40 when the amount of operation of the accelerator pedal 11 by the driver increases. Since the possibility increases, the preshift control to the downshift side is executed. As a result, it is possible to obtain the same operational effects as the above embodiments.

  In each embodiment, the deceleration request determination process may be a process of setting the deceleration request flag FLGb to “ON” when the accelerator pedal 11 is not operated and a brake pedal (not shown) is being operated. Further, the deceleration request determination process may be a process of setting the deceleration request flag FLGb to “ON” when the accelerator pedal 11 is operated and stays with us.

  -In each embodiment, when the determination result of step S18-2 is negative, the pre-shift gear position need not be set. In this case, each sleeve 24 corresponding to a gear transmission mechanism (for example, the first gear transmission mechanism 17) to which no power is transmitted from the engine 12 may be disposed at the neutral position.

  In each embodiment, in step S41, the actual acceleration DVSr is further differentiated, and it is determined whether or not the differentiation result (change amount per unit time of the actual acceleration DVSr) is less than “0 (zero)”. Also good. When the value obtained by differentiating the actual acceleration DVSr is less than “0 (zero)”, it is determined that the acceleration of the vehicle is decreasing, and the acceleration request flag FLGa is set to “ON”. Good.

  In each embodiment, when an external device such as a car navigation system is mounted on a vehicle, various types of information may be transmitted from the external device to the ECU 40. In this case, the ECU 40 may determine whether or not the vehicle is traveling on an uphill road and whether or not the vehicle is traveling on a downhill road based on various types of information from an external device.

  DESCRIPTION OF SYMBOLS 11 ... Accelerator pedal, 12 ... Engine as drive source, 13 ... Automatic transmission, 15, 16 ... Input shaft which comprises power transmission system, 17, 18 ... Gear transmission mechanism which comprises power transmission system, 40 ... Control apparatus , Ascending / descending slope judging means, acceleration request detecting means, preshift control means, deceleration request judging means, gradient obtaining means, vehicle body speed calculating means, ECU as opening obtaining means, AR ... accelerator opening, C1, C2 ... power transmission system , DVSdiff ... acceleration difference corresponding to gradient, VS ... body speed.

Claims (4)

There are two power transmission systems each having a clutch for controlling disconnection / connection of power from a drive source and a transmission mechanism connected in a state where power can be transmitted to the clutch. One clutch included in the one power transmission system is engaged and the other clutch included in the other power transmission system is released so that power from the drive source is transmitted to one of the power transmission systems. A control device for an automatic transmission that executes control for bringing the state into a state,
Uphill / downhill road judging means for judging whether or not the vehicle is traveling on the downhill / downhill road,
When it is determined that the vehicle is traveling on the uphill road by the uphill / downhill road determination means, the acceleration pedal of the accelerator pedal after the detection of the decrease in the acceleration of the vehicle during the operation of the accelerator pedal of the vehicle or the decrease in the acceleration of the vehicle is detected. An acceleration request detecting means for detecting an increase in an operation amount;
When the acceleration request detecting means detects a decrease in the acceleration of the vehicle during the operation of the accelerator pedal or an increase in the operation amount of the accelerator pedal after the detection of a decrease in the acceleration of the vehicle, power from the drive source is generated. Preshift control for performing preshift control in which the speed stage of the other power transmission system that is not transmitted is prepared at a speed stage that is lower than the speed stage selected by one power transmission system to which power is transmitted from the drive source. And a control means for controlling the automatic transmission. A deceleration request determining means for determining whether or not there is a deceleration request for the vehicle when the climbing slope determining means determines that the vehicle is traveling on the downhill;
The pre-shift control means sets the shift speed of the other power transmission system to a speed selected by the one power transmission system when the deceleration request determination means determines that there is a vehicle deceleration request. 2. The control device for an automatic transmission according to claim 1, wherein pre-shift control is performed to prepare at a low speed side gear. The pre-shift control means sets the shift stage of the other power transmission system to a shift stage selected by the one power transmission system when the deceleration request determination means determines that there is no vehicle deceleration request. 3. The automatic transmission control device according to claim 2, wherein pre-shift control is performed to prepare at a high speed side gear. A gradient acquisition means for acquiring the gradient of the road surface on which the vehicle travels;
Vehicle speed calculation means for calculating the vehicle speed of the vehicle;
Opening degree obtaining means for obtaining the opening degree of an accelerator pedal of the vehicle,
The start timing of the preshift control is set by at least one of the gradient acquired by the gradient acquisition unit, the vehicle body speed calculated by the vehicle body speed calculation unit, and the opening acquired by the opening acquisition unit. The control device for an automatic transmission according to any one of claims 1 to 3, wherein:

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