JP2006250161A - Gear shift controller for vehicle in high acceleration - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To bring up an input rotation speed near a target maximum rotation speed in upshift when high acceleration of an fully-opened accelerator to satisfy acceleration request of a driver, regardless of variation in output performance caused by such as individual difference of an engine, aging effect, and difference in used fuel. <P>SOLUTION: Since a reference rotation change rate ΔNTwot is calculated based on an actual input torque T<SB>IN</SB>, the reference rotation change rate ΔNTwot becomes close to a change rate of the turbine rotation speed NT regardless of engine output performance caused by such as difference in used fuel. A gear shift point nomchg when opening fully is changed so that a virtual maximum rotation speed gntista and a target maximum rotation speed ntm match, so that an actual turbine rotation speed NT reaches near the target maximum rotation speed ntm. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a shift control device for a vehicle, and more particularly to upshift control during high acceleration at which the driver's acceleration request is substantially maximum.

(a) shift determination means for outputting an upshift command for upshifting when a predetermined predetermined rotational speed for determination reaches the shift determination speed; and (b) the automatic transmission of the automatic transmission according to the upshift command. Assuming that the input rotation speed increases according to a predetermined reference rotation change rate until the input rotation speed starts to decrease, a virtual maximum rotation speed calculation means for obtaining a virtual maximum rotation speed that is the maximum value of the input rotation speed; (c) learning means for changing the shift determination speed so that the virtual maximum rotation speed approaches a predetermined target maximum rotation speed, and (d) when the driver's acceleration request is large, High-acceleration speed shift control device for a vehicle that upshifts the automatic transmission while appropriately changing the shift determination speed by the learning means so that the input rotation speed reaches the vicinity of the target maximum rotation speed Has been proposed. The device described in Patent Document 1 is one example, and the virtual maximum rotational speed calculation means is the actual input rotational speed of the automatic transmission when the upshift command is output, and the input rotational speed after the upshift command is output. The virtual maximum rotation speed is obtained based on the invalid time until the vehicle starts to decrease and the reference rotation change rate, and the reference rotation change rate is, for example, the accelerator fully open on a flat ground (the driver's acceleration request is 100 %), A constant value is determined in advance for each type of upshift, taking into account changes in rotational speed due to the torque phase and the like.
JP 2004-218799 A

  However, if a fixed value is set in advance as the reference rotation change rate in this way, output will occur due to individual differences in driving force sources, changes over time, or differences in fuel used (such as when regular gasoline is used in a high-octane engine). If the performance varies, the actual rotation change rate and the reference rotation change rate do not necessarily match, and the actual input rotation speed at the time of upshifting reaches the target maximum rotation speed even if the shift determination speed is changed by the learning means. Otherwise, the driver may feel uncomfortable. In other words, even if the virtual maximum rotation speed obtained based on the reference rotation change rate matches the target maximum rotation speed, if the actual input rotation speed change rate and the reference rotation change rate are different, While the maximum value of the input rotational speed of the motor is deviated from the vicinity of the target maximum rotational speed, generally the reference rotational change rate and the target maximum rotational speed are set in consideration of individual differences so that the rotational speed of the driving force source does not become excessive. Therefore, the actual maximum value of the input rotation speed is lower than the target maximum rotation speed.

  The present invention has been made against the background of the above circumstances, and the purpose of the present invention is to change the reference rotational speed regardless of variations in output performance due to individual differences in driving force sources, changes over time, or differences in fuel used. The driver's acceleration request can be met by ensuring that the ratio is always set appropriately so that the input rotation speed reaches the vicinity of the target maximum rotation speed during upshifting when the accelerator is fully open at high acceleration. There is in doing so.

  In order to achieve this object, the present invention provides (a) a shift determining means for outputting an upshift command for upshifting when a predetermined rotation speed for determination reaches a shift determination speed; (b) Assuming that the input rotational speed increases according to a predetermined reference rotational change rate until the input rotational speed of the automatic transmission starts to decrease according to the upshift command, the virtual maximum that is the maximum value of the input rotational speed is assumed. Virtual maximum rotation speed calculation means for obtaining the rotation speed, and (c) learning means for changing the shift determination speed so that the virtual maximum rotation speed approaches a predetermined target maximum rotation speed, d) When the driver's acceleration request is large, the automatic transmission is increased while the shift determination speed is appropriately changed by the learning means so that the input rotation speed reaches near the target maximum rotation speed. In the high-acceleration shift control apparatus for a vehicle to be shifted, (e) a change rate setting means for setting the reference rotation change rate according to an actual input torque of the automatic transmission is provided.

  In such a high-acceleration speed change control device for a vehicle, since the reference rotational change rate for determining the virtual maximum rotational speed is set according to the actual input torque, individual differences in driving force sources, changes over time, and usage Regardless of variations in output performance due to differences in fuel, etc., the reference speed change rate is close to the actual input speed change rate, and the shift is judged by the learning means so that the virtual maximum speed matches the target maximum speed. By changing the speed, the actual input rotational speed at the time of upshifting reaches the vicinity of the target maximum rotational speed, and the driver's acceleration request can be satisfied.

  Examples of the automatic transmission include a plurality of friction engagement devices such as a planetary gear type transmission in which rotating elements of a plurality of planetary gear devices are connected and disconnected by a friction engagement device to establish a plurality of forward shift stages. A stepped transmission that switches between engaged and disengaged states to establish a plurality of shift stages having different gear ratios is preferably used. However, a continuously variable transmission such as a belt type or a toroidal type is used in a stepwise manner. The present invention can also be applied when used in a stepped mode to be changed. In short, a transmission in which the power transmission state is maintained even during an upshift, and there is a delay time (invalid time) after the upshift command until actual shift is performed, during which the input rotational speed increases. For example, the present invention can be applied. The shift determining means is configured to output, for example, an upshift command for switching the engagement / release state of the friction engagement device.

  As the friction engagement device, for example, a hydraulic friction engagement device that is engaged by a hydraulic actuator is used. The hydraulic circuit is switched in accordance with an upshift command, the hydraulic pressure is supplied to the hydraulic actuator, and the piston moves. The delay time until the inertia phase in which the input rotation speed decreases due to the engagement force (torque) generated by the friction engagement device becomes an invalid time. The delay time (invalid time) inevitably has variations due to hardware individual differences of the automatic transmission, and the learning means eliminates the influence of the individual differences. In addition, since the delay time also changes when the viscosity of the hydraulic oil changes, it is desirable to learn the temperature that affects the viscosity as a pamelater.

  The automatic transmission is usually configured so that a plurality of forward shift stages are automatically switched using the operating conditions such as the vehicle speed and the throttle valve opening as parameters, and only when the acceleration demand of the driver is large. Upshift control is performed by the high acceleration shift control device.

  When using an engine that generates power by burning fuel as a driving force source, a fluid power transmission device that transmits power to the automatic transmission via a fluid, such as a torque converter or fluid coupling, is used. It is desirable to provide it. As the driving force source, for example, an engine or an electric motor is used. However, the driving force source can be applied to a hybrid vehicle including both the engine and the electric motor.

  The driver's acceleration request can be determined by, for example, the operation amount of an accelerator operation member such as an accelerator pedal, or the throttle valve opening corresponding to the operation amount. For example, the control is configured to be performed at the time of high acceleration such as about 85% or more.

  As the determination rotation speed for determining the upshift, the output rotation speed and the vehicle speed of the automatic transmission are preferably used, but other rotation speeds such as the input rotation speed can also be used.

  The virtual maximum rotational speed calculation means is, for example, the actual input rotational speed of the automatic transmission when the upshift command is output, the actual input rotational speed from when the upshift command is output until the input rotational speed starts to decrease due to the upshift. Based on the invalid time and the reference rotation change rate, a virtual maximum rotation speed that is a maximum value when the input rotation speed changes at the reference rotation change rate is obtained. Specifically, for example, the virtual maximum rotational speed can be obtained by multiplying the reference rotational speed change rate by an invalid time and adding it to the input rotational speed when the upshift command is output.

  The virtual maximum rotation speed calculation means also detects the input rotation speed at a predetermined timing after the upshift command is output, and changes the input rotation speed at the reference rotation change rate, for example, the inertia phase has started. Various modes are possible such that the calculated value of the input rotational speed at that time may be the virtual maximum rotational speed.

  The learning means, for example, increases or decreases the shift determination speed by a certain value so that the virtual maximum rotation speed approaches the target maximum rotation speed, or a value obtained by multiplying a deviation between the target maximum rotation speed and the virtual maximum rotation speed by a predetermined coefficient. However, when the virtual maximum rotation speed or the actual input rotation speed exceeds a predetermined guard value, the maximum rotation speed is quickly reduced. It is desirable to quickly reduce the shift determination speed by increasing the coefficient.

  The change rate setting means is configured to obtain a reference rotation change rate according to a predetermined map or calculation formula using an input torque as a parameter by experiment, simulation, or the like. For example, each time the high acceleration speed change control is performed, the actual input Although the reference rotation change rate may be obtained from the torque, the reference rotation change rate obtained once may be stored in the storage device and the reference rotation change rate may be read from the storage device from the next time. In addition, when the deviation between the actual maximum value of the input rotation speed and the target maximum rotation speed is large, or when a certain update time is reached, the reference rotation change rate is calculated again at a predetermined timing, and the storage device Various modes are possible, for example, the stored content (reference rotation change rate) may be appropriately updated.

  When the reference rotation change rate is stored in the storage device, it is desirable to store the reference rotation change rate for each type of upshift because the reference rotation change rate varies depending on the gear ratio of the automatic transmission. Instead of storing the reference rotation change rate, the input torque itself or the driving force source torque may be stored, and the reference rotation change rate may be calculated according to a map, an arithmetic expression, or the like for each type of upshift.

  The rate of change of the input rotational speed corresponds to the rate of change of the vehicle speed and changes depending on the driving conditions such as road surface gradient, vehicle weight, and steering angle. You can also find the rate. When the reference rotation change rate is stored in the storage device, it is desirable to store the operation state such as the road surface gradient as a parameter. The shift determination speed changed by the learning means is preferably stored as a parameter such as the road surface gradient, the vehicle weight, the driving state such as the steering angle, or the type of the upshift.

  On the other hand, if the reference rotation change rate or shift determination speed changes depending on the driving condition such as the road surface gradient, the signal processing may become complicated or the learning control may become unstable. It is also possible to obtain the reference rotation change rate without doing so, in which case, for example, a map or an arithmetic expression based on a standard driving state such as flat road running with a road surface gradient of approximately 0 or straight running with a steering angle of approximately 0 Should be set. In order to prevent the input rotational speed and further the rotational speed of the driving force source from becoming excessive due to a downward gradient or the like, it is desirable to obtain a larger reference rotational change rate with a predetermined safety. The target maximum rotation speed may be set to be low in consideration of predetermined safety. In addition, instead of expecting safety, the above-mentioned reference rotational change rate is obtained based on the driving state in which the input rotational speed change rate becomes the largest in normal high acceleration driving (for example, a predetermined downhill traveling with a single ride). It is also possible to set a map and an arithmetic expression.

  The input torque of the automatic transmission may be directly detected by, for example, a torque sensor or the like, but can be obtained from the operating state of the driving force source. As the operating state of the driving force source, for example, in the case of a gasoline engine, it is desirable to use the intake air amount directly related to the torque, the retard amount of the ignition timing, etc., and in the case of an electric motor, the torque is calculated from the motor current. It can be determined as appropriate according to the driving force source. When a torque converter is provided between the driving force source and the automatic transmission, the input torque may be obtained in consideration of the torque ratio (speed ratio) of the torque converter.

  Further, the input torque does not necessarily have to be obtained by using the driving force source torque when the upshift control is performed by the high-acceleration speed change control device. Calculate the driving force source torque in relation to the rotational speed, calculate the driving force source torque from the actual rotational speed at the time of high acceleration upshift, etc. and obtain the input torque, and set the reference rotational change rate It is also possible to correct the preset reference rotation change rate by comparing the torque of the driving force source during high acceleration running with a constant gear position with a preset reference value. Various aspects are possible.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a skeleton diagram of a horizontally installed vehicle drive device such as an FF (front engine / front drive) vehicle. An output of an engine 10 such as a gasoline engine that generates power by combustion of fuel is a torque converter 12, It is transmitted to a driving wheel (front wheel) (not shown) via an automatic transmission 14 and a differential gear device 16. The torque converter 12 includes a pump impeller 20 connected to the crankshaft 18 of the engine 10, a turbine impeller 24 connected to the input shaft 22 of the automatic transmission 14, and a non-rotating member via a one-way clutch 26. And a lockup clutch 32 that directly connects the crankshaft 18 and the input shaft 22 via a damper (not shown). The lockup clutch 32 includes an engagement-side oil chamber. And a frictional engagement by the differential pressure of the fluid in the release side oil chamber. A mechanical oil pump 21 such as a gear pump is connected to the pump impeller 20 and is driven to rotate together with the pump impeller 20 by the engine 10 so as to generate hydraulic pressure for shifting or lubricating. The engine 10 is a driving power source for traveling, and the torque converter 12 is a fluid power transmission device.

  The automatic transmission 14 is coaxially disposed on the input shaft 22 and a carrier and a ring gear are connected to each other to thereby form a so-called CR-CR coupled planetary gear mechanism. A first planetary gear unit 40 and a second planetary gear unit 42; a set of third planetary gear units 46 arranged coaxially on a counter shaft 44 parallel to the input shaft 22; and a shaft end of the counter shaft 44 An output gear 48 that is fixed and meshes with the differential gear device 16 is provided. The components of the planetary gear units 40, 42, 46, that is, the sun gear, the ring gear, and the carrier that rotatably supports the planet gears meshing with them are selectively connected to each other by four clutches C0, C1, C2, and C3. Alternatively, the three brakes B1, B2, and B3 are selectively connected to the housing 28 that is a non-rotating member. Further, the two one-way clutches F1 and F2 are engaged with the housing 28 in the rotational direction. Since the differential gear device 16 is configured symmetrically with respect to the axis (axle), the lower side is not shown.

  The first planetary gear device 40, the second planetary gear device 42, the clutches C0, C1, C2, the brakes B1, B2, and the one-way clutch F1 arranged coaxially with the input shaft 22 are moved forward and reverse in four steps. A one-stage main transmission unit MG is configured, and a set of planetary gear unit 46, clutch C3, brake B3, and one-way clutch F2 arranged on the counter shaft 44 constitute a sub-transmission unit, that is, an underdrive unit U / D. It is configured. In the main transmission unit MG, the input shaft 22 is connected to the carrier K2 of the second planetary gear device 42, the sun gear S1 of the first planetary gear device 40, and the sun gear S2 of the second planetary gear device 42 via the clutches C0, C1, and C2. Each is connected. The ring gear R1 of the first planetary gear unit 40 and the carrier K2 of the second planetary gear unit 42 are connected, and the ring gear R2 of the second planetary gear unit 42 and the carrier K1 of the first planetary gear unit 40 are connected to each other. The sun gear S2 of the second planetary gear unit 42 is connected to the housing 28 that is a non-rotating member via a brake B1, and the ring gear R1 of the first planetary gear unit 40 is a housing 28 that is a non-rotating member via a brake B2. It is connected to. A one-way clutch F1 is provided between the carrier K2 of the second planetary gear unit 42 and the housing 28 which is a non-rotating member. The first counter gear G1 fixed to the carrier K1 of the first planetary gear device 40 and the second counter gear G2 fixed to the ring gear R3 of the third planetary gear device 46 are meshed with each other. In the underdrive unit U / D, the carrier K3 and the sun gear S3 of the third planetary gear device 46 are connected to each other via the clutch C3. Between the sun gear S3 and the housing 28 that is a non-rotating member, A brake B3 and a one-way clutch F2 are provided in parallel.

The clutches C0, C1, C2, and C3 and the brakes B1, B2, and B3 (hereinafter simply referred to as the clutch C and the brake B unless otherwise distinguished) are controlled by a hydraulic actuator such as a multi-plate clutch or a band brake. In the hydraulic friction engagement device, the hydraulic circuit is switched by excitation, de-excitation or manual valve of the linear solenoids SL1, SL2, SL3, SLT and solenoids DSL, S4, SR of the hydraulic control circuit 98 (see FIG. 3). Thus, for example, as shown in FIG. 2, the engaged and released states are switched, and the five forward speeds, the first reverse speed, and the neutral speed stages are established according to the operation position (position) of the shift lever 72 (see FIG. 3). Be made. In FIG. 2, “1st” to “5th” mean the first to fifth forward speeds, and the gear ratio γ () increases from the first speed “1st” to the fifth speed “5th”. = Input rotational speed N _IN / Output rotational speed N _OUT ) decreases. In the figure, “◯” means engagement, “×” means release, and “Δ” means engagement not involved in power transmission. Further, the shift lever 72 is operated in accordance with the shift pattern shown in FIG. 4, for example, the parking position “P”, the reverse travel position “R”, the neutral position “N”, the forward travel positions “D”, “4”, “3”, “ 2 ”and“ L ”, and in the“ P ”and“ N ”positions, neutral is established as a non-drive shift stage that cuts off power transmission. The parking brake mechanically prevents the drive wheels from rotating.

  In FIG. 2, the second to fifth shift speeds are shift speeds at which the engine brake acts when reverse input from the drive wheel side is transmitted to the engine 10 side. This is achieved by a so-called clutch-to-clutch shift in which one of the two friction engagement devices is released while the other is engaged. For example, the 3 → 4 shift or the 4 → 3 shift between the third shift speed and the fourth shift speed is achieved by releasing the clutch C1 and engaging the brake B1, or releasing the brake B1 and engaging the clutch C1. Is done. Even in the first shift stage, the engine brake is applied by engaging the brake B2, and the shift between the second shift stage in this case is a clutch-to-clutch shift.

FIG. 3 is a block diagram for explaining a control system provided in the vehicle for controlling the engine 10, the automatic transmission 14, and the like of FIG. 1. The operation amount A _CC of the accelerator pedal 50 is determined by the accelerator operation amount sensor 51. It is to be detected. The accelerator pedal 50 is largely depressed in response to a driver's acceleration request, corresponds to an accelerator operation member, and an accelerator pedal operation amount A _CC represents an acceleration request amount. The intake pipe of the engine 10 is provided with an electronic throttle valve 56 that has an opening angle (opening) θ _TH corresponding to an accelerator pedal operation amount A _CC by a throttle actuator 54. The engine rotational speed sensor 58 for detecting the rotational speed NE of the engine 10, the intake air quantity sensor 60 for detecting an intake air quantity Q of the engine 10, the intake air to detect the temperature T _A of intake air The temperature sensor 62, the electronic throttle valve 56 in a fully closed state (idle state) and the throttle sensor 64 with an idle switch for detecting the opening _θTH , and the output rotational speed N _OUT (vehicle speed) which is the rotational speed of the counter shaft 44 output rotational speed sensor 66 for detecting the corresponding) to V, the cooling water temperature sensor 68 for detecting the cooling water temperature T _W of the engine 10, a brake switch 70 for detecting the operation of the brake, a shift position of a shift lever 72 (operating position) shift position sensor 74 for detecting a P _SH, the turbine rotational speed NT (= input shaft 22 AT oil temperature sensor 78 for detecting the rotational speed (input rotation speed) N _IN) turbine rotational speed sensor 76 for detecting, a temperature of the hydraulic oil in the hydraulic control circuit 98 AT oil temperature T _OIL, the A counter rotational speed sensor 80 for detecting the rotational speed NC of one counter gear G1 is provided. From these sensors, the engine rotational speed NE, the intake air amount Q, the intake air temperature T _A , the throttle valve opening degree are provided. Signals representing θ _TH , output rotational speed N _OUT , engine cooling water temperature T _W , brake operating state BK, shift position P _SH of shift lever 72, turbine rotational speed NT, AT oil temperature T _OIL , counter rotational speed NC, etc. It is supplied to the electronic control unit 90.

  The electronic control unit 90 includes a so-called microcomputer having a CPU, a RAM, a ROM, an input / output interface, and the like. The CPU uses a temporary storage function of the RAM, and signals according to a program stored in the ROM in advance. By performing the processing, output control of the engine 10, shift control of the automatic transmission 14, and the like are executed, and the engine control and the shift control are divided as necessary. FIG. 5A is a block diagram for explaining main functions executed by the signal processing of the electronic control unit 90. The block diagram includes an engine control unit 100 and a shift control unit 110, and the shift control unit 110 further includes High-acceleration upshift means 120 is provided.

The engine control means 100 basically controls the output of the engine 10, controls the opening and closing of the electronic throttle valve 56 by the throttle actuator 54, controls the fuel injection device 92 for controlling the fuel injection amount, and sets the ignition timing. For the control, an ignition device 94 such as an igniter is controlled. The electronic throttle valve 56 is controlled by, for example, driving the throttle actuator 54 based on the actual accelerator pedal operation amount Acc from the relationship shown in FIG. 6, and increasing the throttle valve opening θ _TH as the accelerator pedal operation amount Acc increases. .

Shift control unit 110 is for performing shift control of the automatic transmission 14 according to the shift position P _SH of the shift lever 72, for example, "D" position, the first speed "1st" to the fifth gear position "5th Shift control is performed using all the forward shift speeds. In this shift control, for example, the shift stage of the automatic transmission 14 is determined based on the actual throttle valve opening θ _TH and the output rotation speed N _OUT from a previously stored shift map (shift condition) shown in FIG. The solenoids DSL, S4, and SR of the hydraulic control circuit 98 are switched ON (excitation) and OFF (non-excitation) so as to establish the determined gear position, and the excitation states of the linear solenoids SL1, SL2, SL3, and SLT are set to duty. It is continuously changed by control. The linear solenoids SL1, SL2, and SL3 can directly control the engagement hydraulic pressures of the brake B1 and the clutches C0 and C1, respectively, and a shift shock such as a change in driving force occurs or the durability of the friction material is impaired. These oil pressures are regulated so that they do not occur. The solid line in FIG. 7 is the upshift line, and the broken line is the downshift line, and the low speed side gear stage where the gear ratio γ increases as the output rotational speed _NOUT decreases or the throttle valve opening _θTH increases. Can be switched to. In the figure, “1” to “5” mean the first shift speed “1st” to the fifth shift speed “5th”.

The shift control means 110 also has a target maximum rotation at which the turbine rotation speed NT, which is the input rotation speed of the automatic transmission 14, is determined separately from the shift map of FIG. so as to reach the vicinity of the speed ntm, and a high acceleration time upshifting means 120 for performing upshift control based on the output rotational speed N _OUT. The high-acceleration upshift means 120 is an embodiment of the high-acceleration speed change control device of the present invention, and as shown in FIG. A speed calculation unit 126, a learning unit 128, a shift determination unit 130, and a shift execution unit 132 are provided, and signal processing is performed according to the flowchart of FIG. 8 are signal processing by the shift determining means 130, step S5 is signal processing by the shift executing means 132, step S7 is signal processing by the change rate calculating means 122, and step S8 is invalid time calculating means 124. Step S9 is signal processing by the virtual maximum rotational speed calculation means 126, and steps S10 to S17 are signal processing by the learning means 128. The change rate calculating means 122 corresponds to a change rate setting means. FIG. 9 is an example of a time chart when an upshift is performed according to the flowchart of FIG.

In step S1 of FIG. 8, it is determined whether or not the accelerator is fully opened, that is, whether or not a high acceleration request is required, for example, when the accelerator pedal operation amount A _CC is 85% or more. Is calculated. The fully open shift point nomchg is determined by adding a learning correction value gwotno to a predetermined reference shift point nochg at a shift determination speed for determining whether to perform an upshift. In this embodiment, the output rotation speed N _OUT is used as the determination rotation speed, and when the output rotation speed N _OUT reaches the fully open shift point nomchg, an upshift determination is performed. The reference shift point nochg and the learning correction value gwotno are stored in a storage device such as a RAM for each type of upshift.

In the next step S3, it is determined whether or not the actual output rotational speed N _OUT is equal to or higher than the fully open shift point nomchg. If N _OUT ≧ nomchg, step S4 is executed to output an upshift command. In step S5, the solenoids DSL, S4, and SR of the hydraulic control circuit 98 are switched ON and OFF according to the upshift command, the clutch C and the brake B are engaged and disengaged, and the linear solenoids SL1, SL2, SL3, Alternatively, the oil pressure is continuously controlled according to a predetermined change pattern or the like by duty control of the SLT, and the upshift is performed as quickly as possible while suppressing the shift shock. In step S6, whether or not it is completed upshift, for example, whether a value obtained by multiplying the speed ratio γ and the output rotational speed N _OUT of the shift stage after the upshift matches the turbine rotation speed NT, When the upshift is completed, step S7 and subsequent steps are executed.

Here, there is a response delay until the pistons of the hydraulic actuators of the clutch C and the brake B actually move to press the friction material and generate an engagement force, so an upshift command is issued at time t ₁ in FIG. After the output, there is a considerable delay time by the time t ₂ when the inertia phase at which the turbine rotational speed NT actually decreases starts. During this time, the turbine rotational speed NT continues to increase, and this delay time is the clutch C It is inevitable that variations occur due to individual differences in hardware of the automatic transmission 14, such as the characteristics of the brake B, the solenoid valve, and the like. The rotational speed ntsftchg in FIG. 9 is the actual turbine rotational speed NT at the time of upshift command, that is, at time t ₁ , and the rotational speed ntmax is upshifted at the actual turbine rotational speed NT at the start of the inertia phase, that is, at time t ₂ . It is the maximum value of the turbine rotation speed NT at the time.

In step S7, the engine torque TE is obtained from the operating state of the engine 10, the input torque (turbine torque) T _IN of the automatic transmission 14 is obtained from the torque ratio of the torque converter 12, and an experiment is performed using the input torque T _IN as a parameter. The reference rotation change rate ΔNTwot is calculated from a map or an arithmetic expression determined in advance by simulation or the like. The engine torque TE is obtained from a predetermined map or an arithmetic expression based on the intake air amount Q directly related to the torque, the retard amount of the ignition device 94, and the like. It is obtained from the speed ratio between the rotational speed NE and the turbine rotational speed NT. The reference rotational change rate ΔNTwot is an expected change rate of the turbine rotational speed NT after the upshift command is output. A map or an arithmetic expression for obtaining the reference rotational change rate ΔNTwot is a steering angle = With reference to a standard operating state of 0, it is determined for each type of upshift in consideration of a change in rotational speed due to a torque phase or the like. The following expression (1) is an example of an arithmetic expression for calculating the reference rotation change rate ΔNTwot based on the input torque T _IN . The automatic transmission 14 gear ratio γ, vehicle weight m, and the final reduction gear reduction ratio and drive It is obtained by using a predetermined coefficient A in accordance with the wheel diameter, power transmission efficiency, rotational resistance due to the torque phase, and the like. The vehicle weight m may be determined in advance, but may be measured by a weight sensor or obtained from acceleration during traveling.
ΔNTwot = T _IN × γ × A / m (1)

In the next step S8, the delay time from the upshift command to the start of the inertia phase, that is, the time (t ₂ -t ₁ ) is calculated as the invalid time tista. In step S9, the turbine rotation at the time when the upshift command is output. Using the speed ntsftchg, the invalid time tista, and the reference rotation change rate ΔNTwot, the virtual maximum rotation speed gntista is calculated according to the following equation (2). The virtual maximum rotational speed gntista is the maximum rotational speed when the turbine rotational speed NT is assumed to increase at the reference rotational change rate ΔNTwot. The high acceleration upshift means 120 has the virtual maximum rotational speed gntista determined in advance. Shift control is performed so as to be close to the target maximum rotational speed ntm. The target maximum rotational speed ntm is as high as possible within a range in which the engine 10 does not overrun, thereby satisfying the driver's acceleration request. In order to prevent the turbine rotational speed NT and further the engine rotational speed NE from becoming excessive due to a downward gradient or the like, the reference rotational change rate ΔNTwot is set to a large value with a predetermined safety in mind, or the target maximum rotational speed ntm Is set lower. Since the invalid time tista varies depending on the viscosity of the hydraulic oil, that is, the oil temperature, and the virtual maximum rotational speed gntista also varies accordingly, the reference shift point nochg and the learning correction value gwotno are set using the oil temperature as a parameter. It is desirable to do.
gntista = ntsftchg + (tista × ΔNTwot) (2)

  In the next step S10, an upper limit rotational speed gntlrnh in which the virtual maximum rotational speed gntista is set above and below the target maximum rotational speed ntm and a lower limit are determined as to whether or not it is a learning dead zone area where it is not necessary to learn the fully open shift point nomchg. Judgment is made based on whether or not the rotation speed is within the range of gntlrnl, and if it is a learning dead zone region, the learning control is stopped and the processing ends as it is. This prevents hunting (slight vertical fluctuation) of the fully open shift point nomchg due to a slight difference between the virtual maximum rotational speed gntista and the target maximum rotational speed ntm.

If the determination in step S10 is NO, that is, if the virtual maximum rotational speed gntista is not in the learning dead zone region, step S11 is executed, and the maximum value of the actual turbine rotational speed NT at the time of shifting, that is, at the start of the inertia phase (time turbine speed ntmax at t ₂₎ determines whether the guard rotational speed gntgd more for a predetermined overrun prevention. The guard rotation speed gntgd is for preventing overrun of the engine 10 and is set to be slightly lower than the fuel cut rotation region in which the operation of the engine 10 is forcibly stopped. If ntmax <gntgd, step S13 is immediately executed, and the following equation (3) is used according to the deviation (ntm−gntista) between the target maximum rotational speed ntm and the virtual maximum rotational speed gntista using a predetermined coefficient. The correction amount gdno is calculated according to the following equation. 3) The coefficient of the equation is made larger than usual, and in step S13, the correction amount gdno is calculated using the coefficient. Since the fully open shift point nomchg is related to the output rotational speed N _OUT , the deviation (ntm−gntista) on the input side is divided by the speed ratio γ of the shift stage before the upshift.
gdno = coefficient × (ntm−gntista) / γ (3)

  In step S14, guard processing is performed to limit the correction amount gdno within a predetermined range. In step S15, a new learning correction value gwotno is calculated by adding the correction amount gdno to the current learning correction value gwotno. In the next step S16, guard processing is performed to limit the learning correction value gwotno within a predetermined range. In step S17, the learning correction value gwotno stored in a storage device such as a RAM is updated to a new value.

By repeating the correction (change) of the full-open shift point nomchg by the high acceleration upshift means 120, the hypothetical time tista varies due to individual differences in hardware such as the clutch C and the brake B. The fully open shift point nomchg converges to a substantially constant value so that the maximum rotation speed gntista substantially matches the target maximum rotation speed ntm. That is, as shown in FIG. 10, when the virtual maximum rotational speed gntista is lower than the target maximum rotational speed ntm in the current high acceleration upshift, the learning correction is made by the correction amount gdno according to the deviation (ntm−gntista). By increasing the value gwotno and further the fully open shift point nomchg, the virtual maximum rotational speed gntista substantially coincides with the target maximum rotational speed ntm in the high-acceleration upshift after learning. Also, the fully open time shift point nomchg is corrected based on the reference rotational speed change rate ΔNTwot obtained in accordance with the input torque T _IN, since the accelerator is an input torque T _IN when the substantially fully open is substantially constant, road gradient Even if the rate of change of the actual turbine speed NT and the maximum value ntmax change due to disturbances such as, the learning correction value gwotno at the fully open shift point nomchg is not affected at all, and the learning correction value gwotno or the fully open shift point is not affected. Under the same driving condition as the standard driving condition with the steering angle = 0 on the flat road that is the basis for calculating the reference rotation change rate ΔNTwot while nomchg is stable, the learning shift of FIG. As shown, the turbine rotation speed NT is changed at a change rate substantially the same as the reference rotation change rate ΔNTwot, and a shift is performed near the target maximum rotation speed ntm.

  As described above, the high-acceleration speed change control device according to the present embodiment uses the turbine rotation speed ntsftchg, the invalid time tista, and the reference rotation change rate ΔNTwot when the upshift command is output, to change the turbine rotation speed NT to the reference rotation. An upshift command is issued to find the virtual maximum rotational speed gntista, which is the maximum rotational speed when changing at a change rate ΔNTwot, and to correct the fully open shift point nomchg so that the virtual maximum rotational speed gntista approaches the target maximum rotational speed ntm. By calculating the reference rotation change rate ΔNTwot taking into account the change in the change rate of the turbine rotation speed NT due to the torque phase and the like after the output, the gear shift is performed near the target maximum rotation speed ntm with high accuracy.

  In addition, since the virtual maximum rotational speed gntista is calculated by obtaining the actual invalid time tista and the shift point nomchg when fully opened is corrected, the hardware of the automatic transmission 14 such as the clutch C and the brake B affecting the invalid time tista As long as the shift point nomchg when fully open converges to a substantially constant value according to the individual difference and the turbine rotational speed NT changes at substantially the same change rate as the reference rotational change rate ΔNTwot, the hardware individual difference of the automatic transmission 14 Regardless of this, the gear shifting is performed stably near the target maximum rotational speed ntm.

On the other hand, in the present embodiment, since the reference rotational change rate ΔNTwot is calculated based on the actual input torque T _IN , regardless of variations in output performance due to individual differences of the engine 10, changes with time, differences in fuel used, and the like. The learning means 128 changes the fully open shift point nomchg so that the reference rotational change rate ΔNTwot becomes close to the actual turbine rotational speed NT change rate and the virtual maximum rotational speed gntista matches the target maximum rotational speed ntm. As a result, the actual turbine rotational speed NT during upshifting reaches the vicinity of the target maximum rotational speed ntm, and the driver's acceleration request can be satisfied.

  As mentioned above, although the Example of this invention was described in detail based on drawing, this is an embodiment to the last, and this invention implements in the aspect which added various change and improvement based on the knowledge of those skilled in the art. Can do.

1 is a skeleton diagram illustrating a vehicle drive device to which the present invention is applied. It is a figure which shows the relationship between the operating state of the some hydraulic friction engagement apparatus of the automatic transmission of FIG. 1, and a gear stage. It is a block diagram explaining the principal part of the control system with which the vehicle drive device of FIG. 1 is provided. It is a figure explaining the shift position of the shift lever of FIG. It is a block diagram explaining the principal part of the function with which the electronic control apparatus of FIG. 3 is provided. It is a figure which shows the relationship between the throttle-valve opening degree of an electronic throttle valve controlled by the engine control means of FIG. 5, and an accelerator operating quantity. It is a figure explaining an example of the shift map which switches the gear stage of an automatic transmission automatically according to a driving | running state by the shift control means of FIG. FIG. 6 is a flowchart for specifically explaining the processing contents of the high acceleration upshift means of FIG. 5. FIG. FIG. 9 is an example of a time chart illustrating a change in rotational speed when upshift control is performed according to the flowchart of FIG. 8 and various parameters used in learning control. FIG. 9 is an example of a time chart showing a change in rotational speed at the time of upshift before and after a fully open shift point nomchg is corrected according to the flowchart of FIG. 8.

Explanation of symbols

14: Automatic transmission 90: Electronic control device 120: High-acceleration upshift means (high-acceleration speed change control device) 122: Change rate calculation means (change rate setting means) 126: Virtual maximum rotation speed calculation means 128: Learning means 130: Shift determination means NT: Turbine rotation speed (input rotation speed) N _OUT : Output rotation speed (rotation speed for determination) nomchg: Full-open shift point (shift determination speed) tista: Invalid time ΔNTwot: Reference rotation change rate gntista: Virtual maximum rotation speed ntm: Target maximum rotation speed

Claims (1)

Shift determining means for outputting an upshift command for upshifting when a predetermined determination rotational speed reaches a shift determination speed;
Assuming that the input rotational speed increases according to a predetermined reference rotational change rate until the input rotational speed of the automatic transmission starts to decrease in accordance with the upshift command, the virtual maximum rotational speed that is the maximum value of the input rotational speed is determined. A desired virtual maximum rotation speed calculation means;
Learning means for changing the shift determination speed so that the virtual maximum rotation speed approaches a predetermined target maximum rotation speed;
A vehicle that upshifts the automatic transmission while appropriately changing the shift determination speed by the learning means so that the input rotation speed reaches near the target maximum rotation speed when a driver's acceleration request is large In the high acceleration speed change control device,
A high-acceleration speed change control device for a vehicle characterized by comprising change rate setting means for setting the reference rotation change rate in accordance with an actual input torque of the automatic transmission.

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