JP3572609B2 - Transmission control device for continuously variable transmission - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention belongs to the technical field of a shift control device of a continuously variable transmission having a manual mode function in which a fixed gear ratio can be selected manually from a plurality of shift speeds manually.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, as a shift control device of a continuously variable transmission having a manual mode function, for example, one described in Japanese Patent Application Laid-Open No. 9-264415 is known.
[0003]
This publication describes a shift control device of a continuously variable transmission having a manual mode function in which a fixed gear ratio can be selected sequentially from a plurality of shift stages manually.
[0004]
Japanese Patent Application Laid-Open No. 5-126239 discloses that in a transmission control device for a continuously variable transmission, when a target value changes stepwise due to sudden depression of an accelerator, sudden release of a stride, etc., a steady control target value is changed to a transient control target value. Is described, and a shift control device that improves shift transient response characteristics is described.
[0005]
Therefore, it is estimated that the shift control is performed using the shift time constant according to the shift ratio deviation, which is the difference between the current shift ratio and the steady target shift ratio after the shift operation, during the shift operation in the manual mode. can do.
[0006]
[Problems to be solved by the invention]
However, in the shift control in the conventional manual mode, if the shift in the manual mode is continuously operated, the shift time constant does not change while maintaining the shift time constant in each one-step shift. In addition, there is a problem that the amount of change in the target gear ratio per unit time increases, in other words, the gear speed increases.
[0007]
That is, in the shift in the normal manual mode, as shown in FIG. 9, for example, when performing 4 → 3 shift, a shift time constant is set based on the shift ratio deviation a, and a transient target shift ratio is calculated. Is done. Thereafter, when a 3 → 2 shift is performed, a shift time constant is set based on the shift ratio deviation b, and a transient target shift ratio is calculated. In other words, if the shift time constant is constant, the time t until the steady target gear ratio (attained gear ratio) is reached is the same.
[0008]
However, if the 3 → 2 shift operation is performed in the manual mode after the 4 → 3 shift operation and before the actual speed ratio reaches the speed ratio corresponding to the third speed, as shown in FIG. The speed ratio deviation c (> b) from the time point when the 3 → 2 speed change operation is performed to the attained speed ratio corresponding to the second speed becomes a large deviation, so that the speed ratio deviation c reaches the second speed at the same time t. Since the shift time constant is set, the change in the gear ratio per unit time increases, in other words, the shift speed increases.
[0009]
As a result, the inertia torque (inertia torque) associated with the shift affects components such as the clutch and the torque converter, and may cause clutch slippage.
[0010]
SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and an inertia torque determined by a change in output rotation of a transmission can be achieved by reducing a shift speed by correcting a shift time constant during a continuous shift operation in a manual mode. It is an object of the present invention to provide a shift control device for a continuously variable transmission that prevents the influence of clutch slippage or the like caused by acting on each component.
[0011]
[Means for Solving the Problems]
According to the first aspect of the present invention, in addition to the stepless smooth shift, the shift control of the continuously variable transmission having a manual mode function capable of manually selecting a fixed speed ratio from a plurality of shift stages manually. In the device,
Manual mode determining means for determining whether or not a shift is being performed in the manual mode;
A gear ratio deviation calculating means for calculating a gear ratio deviation between the current gear ratio and the attained gear ratio after the gear shifting operation during manual mode gear shifting;
Shift time constant setting means for setting a shift time constant necessary for calculating a transient target speed ratio from a steady attained speed ratio according to the magnitude of the calculated speed ratio deviation;
A continuous shifting operation determining means for determining whether or not a continuous shifting operation in which a first shifting operation is performed by a manual shifting operation and then a second shifting operation is performed before the actual speed ratio reaches the attained speed ratio after shifting. When,
Shift time constant correction means for correcting the shift time constant set by the shift time constant setting means to reduce the shift speed when it is determined that the shift time is being operated;
It is characterized by having.
[0012]
According to a second aspect of the present invention, in the shift control device for a continuously variable transmission according to the first aspect,
The continuous gear shifting operation determining means determines that the gear ratio deviation absolute value, which is the absolute value of the difference between the current gear ratio and the attained gear ratio after the gear shifting operation, is greater than the gear ratio deviation during each single-gear shift. When it is larger than the set threshold value, it is characterized in that it is means for judging that it is a continuous shifting operation.
[0013]
According to a third aspect of the present invention, in the shift control device for a continuously variable transmission according to the second aspect,
The time constant correction means is variably set such that the larger the absolute value of the gear ratio deviation calculated by the continuous gear shift operation determination means and the variable corresponding to the inertia calculated from the transmission output rotation speed at that time, the slower the shift speed. Means for correcting the shift time constant.
[0014]
Function and Effect of the Invention
In the invention according to claim 1 of the present invention, the manual mode determining means determines whether or not the shift is in a manual mode in which a fixed gear ratio is manually selected from a plurality of shift speeds. The ratio deviation calculating means calculates a gear ratio deviation between the current gear ratio and the attained gear ratio after the gear shifting operation during the manual mode gear shift, and the gear ratio time constant setting means calculates the gear ratio deviation according to the magnitude of the calculated gear ratio deviation. A shift time constant required for calculating a transient target gear ratio from a steady attained gear ratio is set, and a first gear shift operation is performed by a manual gear shift operation in a continuous gear shift operation determining means. Before the actual speed ratio reaches the attained speed ratio after shifting, it is determined whether or not the second speed change operation is performed during a continuous speed change operation. When it is determined, a correction to slow the shifting speed is added to the shift time constant set by the speed change time constant setting means.
[0015]
That is, when the speed change time constant is set based on the speed ratio deviation before and after the speed change regardless of the presence or absence of the continuous speed change operation, the speed ratio deviation becomes larger during the continuous speed change operation than during the normal speed change operation. When the shift time constant is set so that the shift is completed within the shift time, the shift speed is faster during a continuous shift operation than during a normal shift operation.
[0016]
On the other hand, when the continuous shifting operation time determining means determines that a continuous shifting operation is being performed, the shifting time constant correcting means reduces the shifting speed to the shifting time constant set by the shifting time constant setting means. Is added, it is possible to suppress an increase in the shift speed even when a continuous shift operation is performed.
[0017]
Therefore, by reducing the shift speed by correcting the shift time constant during the continuous shift operation in the manual mode, the influence of clutch slip and the like due to the fact that the inertia torque determined by the change in the output rotation of the transmission acts on each part of the transmission. Can be prevented.
[0018]
In the invention according to claim 2 of the present invention, in the continuous shift operation time determining means, the speed ratio deviation absolute value which is the absolute value of the difference between the current speed ratio and the attained speed ratio after the speed change operation is: When it is larger than a threshold value set to a value larger than the speed ratio deviation at the time of each one-speed shift, it is determined that a continuous shift operation is being performed.
[0019]
That is, in the continuous speed change operation, after the first speed change operation, the second speed change operation is performed before the actual speed ratio reaches the attained speed ratio after the speed change. The speed ratio deviation is a value larger than the speed ratio deviation at the time of each one-step speed change.
[0020]
Therefore, it is possible to accurately judge the time of the continuous speed change operation while using a speed ratio deviation, which is the setting information of the speed change time constant, as a criterion.
[0021]
In the invention according to claim 3 of the present invention, the shift time constant correction means calculates the speed ratio deviation absolute value calculated by the continuous shift operation time determination means and the transmission output rotation speed at that time. As the inertia-equivalent variable is larger, the shift time constant is corrected by a variable setting that reduces the shift speed.
[0022]
That is, since the inertia torque is determined by a change in the transmission output rotation, the magnitude of the inertia torque can be estimated from an inertia-equivalent variable calculated from the absolute value of the gear ratio deviation and the transmission output rotation speed (vehicle speed).
[0023]
Therefore, by taking in the element of the number of revolutions that can estimate the magnitude of the inertia torque and correcting the shift time constant, the inertia acting on each part of the transmission during the continuous shift operation regardless of the driving condition or the driving condition. Optimal shift time constant correction can be performed to keep the magnitude of the torque constant.
[0024]
BEST MODE FOR CARRYING OUT THE INVENTION
A shift control device for a continuously variable transmission according to the present invention will be described in detail with reference to the drawings.
[0025]
[Configuration of transmission unit and transmission control device of continuously variable transmission]
1 and 2 show a toroidal type continuously variable transmission provided with a shift control device for a continuously variable transmission according to the present invention. FIG. 1 is a longitudinal sectional side view showing a transmission unit of the toroidal type continuously variable transmission. FIG. 3 is a diagram illustrating a shift control device of the toroidal-type continuously variable transmission.
[0026]
First, a transmission unit which is a main part of a toroidal type continuously variable transmission will be described with reference to FIG. This transmission unit includes an input shaft 20 to which rotation from an engine (not shown) is transmitted. As shown in FIG. 1, the input shaft 20 has an end remote from the engine via a bearing 22 in a transmission case 21. And a central portion is rotatably supported in a middle wall 23 of the transmission case 21 via a bearing 24 and a hollow output shaft 25.
[0027]
The input shaft 20 supports the input cone disc 1, the hollow output shaft 25 supports the output cone disc 2, and the input and output cone discs 1 and 2 have their toroidal curved surfaces 1a and 2a facing each other. Coaxial arrangement.
[0028]
A pair of power rollers 3, 3 disposed on both sides of the input shaft 20 with the input shaft 20 interposed therebetween are interposed between the opposed toroid curved surfaces 1a, 2a of the input / output cone disks 1, 2, and these power rollers 3, 3 The following configuration is adopted in order to clamp the pressure between the input and output cone disks 1 and 2.
[0029]
That is, a loading nut 26 is screwed into the end of the input shaft 20 on the bearing 22 side, the cam disk 27 is prevented from falling off by the loading nut 26 and is rotationally engaged on the input shaft 20, and the toroid of the input cone disk 1 A loading cam 28 is interposed between the end surface far from the curved surface 1a, and rotation from the input shaft 20 to the cam disk 27 is transmitted to the input cone disk 1 via the loading cam 28.
[0030]
Here, the rotation of the input cone disk 1 is transmitted to the output cone disk 2 via the rotation of the two power rollers 3, 3, and during this transmission, the loading cam 28 generates a thrust proportional to the transmission torque, and , 3 are narrowed between the input and output cone disks 1, 2 to enable the power transmission.
[0031]
The output cone disk 2 is wedge-fitted to an output shaft 25, and an output gear 29 is fitted on the output shaft 25 so as to rotate integrally.
[0032]
The output shaft 25 is further rotatably supported in an end cover 31 of the transmission case 21 via a radial / thrust bearing 30, and the input shaft 20 is separately provided in the end cover 31 via a radial / thrust bearing 32. It is rotatably supported. Here, the radial and thrust bearings 30 and 32 are butted so as not to approach each other at the start of the spacer 33, and the axis of the corresponding output gear 29 and the input shaft 20 are set so as not to be displaceable relative to each other. Make contact in the direction.
[0033]
With the above configuration, the thrust acting between the input and output cone disks 1 and 2 by the loading cam 28 becomes an internal force that sandwiches the spacer 33 and does not act on the transmission case 21.
[0034]
As shown in FIG. 2, the power rollers 3, 3 are rotatably supported by trunnions 41, 41. Each of the trunnions 41, 41 is rotatably supported at both ends of an upper link 43 by a spherical joint 42. The lower end is rotatably and swingably connected to both ends of a lower link 45 by a spherical joint 44.
[0035]
The upper link 43 and the lower link 45 are supported by the spherical joints 46 and 47 at the center of the transmission case 21 so as to be vertically swingable, and the two trunnions 41 and 41 are vertically moved synchronously in opposite directions. To get.
[0036]
A shift control device that performs a shift by vertically moving the two trunnions 41 in synchronization with each other in the above-described manner will be described with reference to FIG.
[0037]
Each of the trunnions 41, 41 is provided with a piston 6, 6 for individually moving the trunnions 41 in the vertical direction, and defines upper chambers 51, 52 and lower chambers 53, 54 on both sides of the pistons 6, 6, respectively. . To control the strokes of the pistons 6 and 6 in opposite directions, a shift control valve 5 is provided.
[0038]
Here, the shift control valve 5 slidably fits the spool-type inner valve element 5a and the sleeve-type outer valve element 5b so that the outer valve element 5b can slide on the valve case 5c. It is configured by fitting.
[0039]
The speed change control valve 5 has an input port 5d connected to a pressure source 55, one communication port 5e connected to the piston chambers 51 and 54, and the other communication port 5f connected to pistons 52 and 53, respectively.
[0040]
Then, the inner valve element 5a cooperates with the cam surface of the precess cam 7 fixed to the lower end of the one trunnion 41 via a bell crank type shift lever 8, and the outer valve element 5b functions as a stepping motor 4 as a shift actuator. Then, drive engagement is performed in a rack and pinion type.
[0041]
The operation command of the shift control valve 5 is given by the step motor 4 responsive to the actuator drive position command Asstep (step position command) as a stroke to the outer valve body 5b via a rack and pinion.
[0042]
With this operation command, when the outer valve body 5b of the shift control valve 5 is displaced from the neutral position relative to the inner valve body 5a to, for example, the position of FIG. Is supplied to the chambers 52 and 53, the other chambers 51 and 54 are drained, and the outer valve body 5b of the transmission control valve 5 is relatively moved with respect to the inner valve body 5a. When the shift control valve 5 is opened by being displaced in the opposite direction from the neutral position, the fluid pressure from the pressure source 55 is supplied to the chambers 51 and 54, while the other chambers 52 and 53 are drained and the two trunnions 41 and 41 are discharged. Is displaced in the corresponding vertical direction in the figure by the fluid pressure via the pistons 6 and 6 in opposite directions.
[0043]
Thus both the power rollers 3 and 3, will be rotating shaft axis O ₁ is offset (offset amount y) from the position shown intersecting the rotation axis O ₂ of the input and output cone discs 1 and 2, the power by nuclear offset rollers 3,3 in swinging component force from the input and output cone discs 1 and 2, tilting (tilting angle phi) around the swing axis O ₃ orthogonal to the rotation axis O ₁ of the self has been continuously variable It can be performed.
[0044]
During such shifting, the precess cam 7 coupled to the lower end of the one trunnion 41 controls the above-described vertical movement (offset amount y) and the tilt angle φ of the trunnion 41 and the power roller 3 via the shifting link 8. Feedback is mechanically fed back to the inner valve body 5a of the valve 5 as indicated by x.
[0045]
When the speed ratio command value corresponding to the actuator drive position command Asstep to the step motor 4 is achieved by the stepless speed change, the mechanical feedback through the precess cam 7 causes the inner valve of the speed change control valve 5 to move. and the body 5a, is returned to a relatively initial neutral position with respect to the outer valve member 5b, at the same time, both the power rollers 3 and 3, the rotation axis 0 ₂ of the rotation axis O ₁ is output cone discs 1 and 2 By returning to the illustrated position intersecting with the above, it is possible to maintain the state of achievement of the above-mentioned speed ratio command value.
[0046]
Since the aim of the control is to make the power roller tilt angle φ a value corresponding to the gear ratio command value, the precess cam 7 basically has to feed back only the power roller tilt angle φ. Here, the reason why the power roller offset amount y is also fed back is to avoid a hunting phenomenon of the shift control by giving a damping effect of preventing the shift control from becoming oscillating.
[0047]
The actuator drive position command Asstep to the step motor 4 is set by the controller 61.
[0048]
For this purpose, as shown in FIG. 2, a signal from a throttle opening sensor 62 for detecting an engine throttle opening TVO, a signal from a vehicle speed sensor 63 for detecting a vehicle speed VSP, and a rotation speed of the input cone disk 1 are provided to the controller 61 as shown in FIG. A signal from an input rotation sensor 64 for detecting Ni (or an engine rotation speed Ne), a signal from an output rotation sensor 65 for detecting a rotation speed No of the output cone disk 2, and an oil temperature for detecting a transmission working oil temperature TMP. A signal from a sensor 66 and a line pressure P _L from the hydraulic pressure source 55 are detected (normally, the line pressure P _L is detected by an internal signal of the controller 61 because the line pressure P _L is controlled by the controller 61). , A signal from the engine rotation sensor 68 for detecting the engine rotation speed Ne, and range information from the inhibitor switch 60 Signal, a signal for UP / DOWN information from the UP / DOWN switch 69, a selection mode signal from the mode selection switch 70, a torque down permission signal from the engine control device 310, and a signal from the anti-skid control device (ABS) 320. , The TCS control signal from the traction control device (TCS) 330, and the ASCD cruise signal from the constant-speed traveling device 340.
[0049]
The controller 61 sets the actuator drive position command Asstep (shift command value) to the step motor 4 by the following calculation based on the above various input information.
[0050]
[Controller configuration]
In the present embodiment, the controller 61 is configured as shown in FIG.
[0051]
The shift map selection unit 71 selects a shift map in accordance with various conditions such as the oil temperature TMP detected by the sensor 66 in FIG. 2 and whether or not the exhaust purifying catalyst is being activated.
[0052]
A description will be given of the case where the shift map selected in this way is, for example, as shown in FIG. 4. The reaching input rotation speed calculating section 72 calculates the throttle opening TVO and the throttle opening TVO detected by the sensors 62 and 63 in FIG. From the vehicle speed VSP, based on a shift map corresponding to the shift diagram shown in FIG. 3, a reached input rotational speed Ni ^* to be a steady target input rotational speed in the current operating state is searched for and obtained.
[0053]
Attained gear ratio calculation unit 73, by dividing the arrival input rotation speed Ni ^* by the transmission output rotational speed No detected by the sensor 65 of FIG. 2, a steady target speed ratio corresponding to the arrival input rotation speed Ni ^* Request attained gear ratio i ^* is.
[0054]
The shift time constant calculation unit 74 includes a selection range (forward normal travel range D, forward sports travel range Ds), vehicle speed VSP, throttle opening TVO, engine speed Ne, accelerator pedal operation speed, torque down control device (not shown). ), The speed reduction according to various conditions such as a torque reduction amount signal, a torque reduction permission signal, an anti-skid control signal, a traction control signal, a constant speed traveling signal, and a speed ratio deviation RtoERR from a target speed ratio Ratio0 described later. A first shift time constant Tg1 and a second shift time constant Tg2 of the control are set, and a deviation Eip between the attained speed ratio i ^* and the target speed ratio Ratio0 is calculated.
[0055]
Here, the first shift time constant Tg1 and the second shift time constant Tg2, which are set to correspond to the secondary delay system of the toroidal type continuously variable transmission, set the shift responsiveness to the attained speed ratio i ^* . The target speed ratio calculation unit 75 performs a transient process for realizing the attained speed ratio i ^* with a speed response determined by the first speed time constant Tg1 and the second speed time constant Tg2. The target speed ratio Ratio0 and the intermediate speed ratio Ratio00 at each time are calculated, and only the target speed ratio Ratio0 is output.
[0056]
The input torque calculation unit 76 obtains the transmission input torque Ti by a known method, first obtains the engine output torque from the throttle opening TVO and the engine speed Ne, and then obtains the input / output speed (Ne, Ni), the torque ratio t of the torque converter is obtained from the speed ratio, and finally the engine output torque is multiplied by the torque ratio t to calculate the transmission input torque Ti.
[0057]
The torque-shift-compensated transmission ratio calculation unit 77 uses the transient target transmission ratio Ratio0 and the transmission input torque Ti to remove a torque shift (incorrect transmission ratio) peculiar to a toroidal-type continuously variable transmission. A compensation speed ratio TSrto is calculated.
[0058]
Here, a supplementary explanation of the torque shift of the toroidal type continuously variable transmission is as follows. During transmission of the toroidal type continuously variable transmission, the power rollers 3, 3 are connected between the input and output cone disks 1, 2 as described above. The clamping causes a deformation of the trunnion 41, which changes the position of the precess cam 7 at the lower end of the trunnion, causing a change in the path length of the mechanical feedback system composed of the precess cam 7 and the speed change link 8, thereby causing The torque shift is generated.
[0059]
Therefore, the torque shift of the toroidal-type continuously variable transmission differs depending on the target speed ratio Ratio0 and the transmission input torque Ti, and the torque shift compensation speed ratio calculation unit 77 searches the torque shift compensation speed ratio TSrto from these two-dimensional maps. Ask by.
[0060]
The actual speed ratio calculating unit 78 calculates the actual speed ratio Ratio by dividing the transmission input speed Ni by the transmission output speed No detected by the sensor 65 in FIG. The speed ratio deviation calculating section 79 subtracts the actual speed ratio from the target speed ratio Ratio0 to obtain a speed ratio deviation RtoERR (= Ratio0-Ratio) between the two.
[0061]
The first feedback (FB) gain calculator 80 calculates a gear ratio feedback correction amount by well-known PID control (P is proportional control, I is integration control, and D is differential control) according to the gear ratio deviation RtoERR. Among the feedback gains of the respective controls, a first proportional control feedback gain fbpDATA1, an integral control feedback gain fbiDATA1, and a differential control feedback gain to be set according to the transmission input rotation speed Ni and the vehicle speed VSP. fbdDATA1 is obtained.
[0062]
These first feedback gains fbpDATA1, fbiDATA1 and fbdDATA1 are previously determined as a two-dimensional map of the transmission input rotation speed Ni and the vehicle speed VSP, and based on this map, the transmission input rotation speed Ni and the vehicle speed VSP are used to determine the input speed and the vehicle speed VSP. Shall be sought.
[0063]
Second feedback (FB) gain calculation unit 81, among the feedback gain used when calculating the speed ratio feedback correction amount by the PID control, the to be set in accordance with the transmission hydraulic oil temperature TMP and the line pressure P _L 2, the feedback gain fbpDATA2 for proportional control, the feedback gain fbiDATA2 for integral control, and the feedback gain fbdDATA2 for differential control are obtained.
[0064]
These second feedback gain fbpDATA2, fbiDATA2, fbdDATA2 is set in advance as a two-dimensional map of the working oil temperature TMP and the line pressure _{P L,} determined by the search from the working oil temperature TMP and the line pressure _{P L} based on this map Shall be.
[0065]
The feedback gain calculation unit 83 multiplies the first feedback gain and the second feedback gain by the corresponding feedback gains, and obtains a proportional control feedback gain fbpDATA (= fbpDATA1 × fbpDATA2) and an integral control feedback gain fbiDATA ( = FbiDATA1 × fbiDATA2) and the differential control feedback gain fbdDATA (= fbdDATA1 × fbdDATA2).
[0066]
The PID control unit 84 uses the feedback gain obtained as described above to calculate the gear ratio feedback correction amount FBrto by the PID control according to the gear ratio deviation RtoERR,
The speed ratio feedback correction amount by the proportional control is obtained by RtoERR × fbpDATA,
Next, the gear ratio feedback correction amount by the integral control is obtained by ∫RtoERR × fbiDATA,
Further, the gear ratio feedback correction amount by the differential control is obtained by (d / dt) RtoERR × fbdDATA,
Finally, the sum of the three is set as a gear ratio feedback correction amount FBrto (= RtoERR × fbpDATA + ∫RtoERR × fbiDATA + (d / dt) RtoERR × fbdDATA) by PID control.
[0067]
The target gear ratio correction unit 85 corrects the target gear ratio Ratio0 by the torque shift compensation gear ratio TSrto and the gear ratio feedback correction amount FBrto to obtain a corrected target gear ratio DsrRTO (= Ratio0 + TSrto + FBrto). The target step number (actuator target drive position) calculation unit 86 obtains the target step number (actuator target drive position) DsrSTP of the step motor (actuator) 4 for realizing the corrected target gear ratio DsrRTO by searching a map.
[0068]
The step motor drive position command calculation unit 87 determines that the step motor 4 is capable of setting the target step number DsrSTP during one control cycle even at the limit drive speed of the step motor 4 set by the step motor drive speed setting unit 88 based on the transmission operating oil temperature TMP and the like. When the step motor 4 cannot be displaced, the achievable limit position achievable at the above limit drive speed of the step motor 4 is set as the drive position command Astep to the step motor 4, and the step motor 4 sets the target step number DsrSTP during one control cycle. When it can be displaced, the target step number DsrSTP is directly used as the drive position command Astep to the step motor 4.
[0069]
Accordingly, the drive position command Asstep can always be regarded as the actual drive position of the step motor 4.
[0070]
The step motor 4 is displaced in the direction and the position corresponding to the drive position command Astep to cause the outer valve body 5b of the speed change control valve 5 to stroke through the rack and pinion, as described above for the toroidal type continuously variable transmission. The speed can be changed as desired.
[0071]
When a speed ratio command value corresponding to the drive position command Asstep is achieved by this shift, mechanical feedback via the precess cam 7 causes the inner valve element 5a of the shift control valve 5 to move relative to the outer split element 5b. is returned to the initial neutral position, at the same time, both the power rollers 3, 3, by the rotation axis 0 ₁ returns to the illustrated position that intersects the rotation axis 0 ₂ of the input and output cone discs 1 and 2, the gear ratio command The achievement state of the value can be maintained.
[0072]
In the present embodiment, a step motor follow-up determination section 89 is additionally provided.
[0073]
The step motor follow-up determination section 89 determines whether or not the step motor 4 can follow the target step number (actuator target drive position) DsrSTP corresponding to the corrected target gear ratio DsrRTO as follows.
[0074]
That is, the determination unit 89 first obtains a step number deviation (actuator driving position deviation) △ STP between a target step number (actuator target driving position) DsrSTP and a driving position command Asstep that can be regarded as an actual driving position.
[0075]
The determination unit 89 determines the step number deviation (actuator drive) in which the step motor 4 cannot be canceled within one control cycle even at the limit drive speed of the step motor 4 set as described above by the step motor drive speed setting unit 88. position deviation lower limit △ _{STP LIM} step speed deviation than the) (actuator drive position deviation) △ when STP is small (△ STP <△ _{STP LIM),} the target number of steps the step motor 4 corresponding to the corrected target gear ratio DsrRTO (Actuator target drive position) It is determined that DsrSTP can be followed,
Conversely, when △ STP ≧ △ STP _LIM, it is determined that the step motor 4 cannot follow the target step number (actuator target drive position) DsrSTP.
[0076]
If the determination unit 89 determines that the step motor 4 can follow the target step number (actuator target drive position) DsrSTP corresponding to the corrected target speed ratio DsrRTO, the PID control unit 84 determines the PID as described above. The calculation of the gear ratio feedback correction amount FBrto by the control is continued.
[0077]
In this way, when it is determined that the step motor 4 cannot follow the target step number (actuator target drive position) DsrSTP, the gear ratio feedback correction amount 積分 RtoERR × fbiDATA by the integral control is held at the value at the time of the determination. To the PID control unit 84 to perform the operation.
[0078]
Further, in the present embodiment, when the step motor drive position command calculation unit 87 cannot displace the step motor 4 to the target step number DsrSTP during one control cycle even at the limit drive speed of the step motor 4, the step motor 4 The achievable limit position achievable at the drive speed is set as a drive position command Astep to the step motor 4, and this drive position command Astep is used as an actual drive position of the step motor 4 by the determination unit 89 for the step motor follow-up determination. I decided to contribute
The actual drive position of the step motor 4 necessary for making such a follow-up determination is detected by the drive position command Astep from the transmission control device to the step motor 4. This can be performed at low cost without relying on the actual measurement of the actual driving position.
[0079]
Further, in the present embodiment, the step motor follow-up possibility determining section 89 determines the step number deviation (actuator drive position deviation) between the target step number (actuator target drive position) DsrSTP and the actual drive position (drive position command) Asstep. When ΔSTF is smaller than the reference deviation △ STP _LIM determined for each limit drive speed of the stepping motor 4 (△ STP <△ STP _LIM ), the stepping motor 4 sets the target step corresponding to the corrected target speed ratio DsrRTO. Number (actuator target drive position) DsrSTP, and conversely, when 、 STP ≧ △ STP _LIM, it is determined that the step motor 4 cannot follow the target step number (actuator target drive position) DsrSTP. To do
It is possible to reliably determine that the stepping motor 4 can follow, regardless of the limit driving speed of the stepping motor 4 that changes variously depending on the oil temperature TMP or the like.
[0080]
[Overall shift control]
When the controller 61 of FIG. 2 is configured by a microcomputer, the shift control described with reference to FIG. 3 is executed by the programs of FIG. 5 and FIG.
[0081]
FIG. 5 shows the entire shift control, and this routine is executed, for example, every 10 ms. First, in step 91, the shift time constant calculator 74 (FIG. 3) inputs the vehicle speed VSP detected by the vehicle speed sensor 63 (FIG. 2), the engine speed Ne detected by the engine speed sensor 68 (FIG. 2), and The transmission input rotation speed Ni detected by the rotation sensor 64 (FIG. 2), the throttle opening TVO detected by the throttle opening sensor 62 (FIG. 2), and range information (automatic transmission) from the inhibitor switch 60 (FIG. 2). (D) range, sports running (S) range, etc.) are read.
[0082]
Next, in step 92, the reached input speed calculating unit 72 (FIG. 3) calculates the actual speed ratio Ratio by dividing the input speed Ni by the transmission output speed No. Next, at step 93, the reached input rotational speed Ni ^* is searched and obtained from the throttle opening TVO and the vehicle speed VSP based on the shift map as shown in FIG.
[0083]
Next, in step 94 as the attained speed ratio setting means, the attained speed ratio calculating section 73 (FIG. 3) divides the attained input speed Ni ^* by the transmission output speed No to obtain the attained speed ratio i ^* . calculate. Next, in step 95 as a deviation calculating means, the shift time constant calculating section 74 (FIG. 3) uses the target speed ratio Ratio0 calculated in the previous routine from the attained speed ratio i ^* (this is calculated in a later step 99). Is subtracted to calculate the deviation Eip.
[0084]
Next, at step 96, it is determined whether or not there is a stepped shift by mode switching and manual shift (hereinafter, referred to as "switch shift"). Specifically, in response to a selection mode signal from the mode selection switch 70 (FIG. 2), the presence or absence of switching between the power mode and the snow mode is detected, and a manual range signal is output from the inhibitor switch 60 (FIG. 2). At the same time, it is determined whether or not a signal regarding UP / DOWN information has been detected from the UP / DOWN switch 69 (FIG. 2). Next, in steps 97 and 98 as the mode setting means and in step 99 as the target gear ratio setting means, the shift time constant calculating section 74 (FIG. 3) sets the time constant calculation mode and the first and second shift time constants. Tg1 and Tg2, a target speed ratio Ratio0 and an intermediate speed ratio Ratio00 are calculated, respectively.
[0085]
Thereafter, in step 100, the torque shift compensation speed ratio calculation unit 77 (FIG. 3) calculates the torque shift compensation speed ratio TSrto from a map relating to the target speed ratio Ratio0 and the transmission input torque Ti. Next, in step 101, the PID control unit 84 (FIG. 3) calculates the gear ratio feedback correction amount FBrto by PID control. Next, in step 102, the target gear ratio correction unit 85 (FIG. 3) calculates the corrected target gear ratio DsrRTO by adding the torque shift compensation gear ratio TSrto and the gear ratio feedback correction amount FBrto to the target gear ratio Ratio0. Next, in step 103, a drive position command Asstep to the step motor 4 (FIG. 2) is calculated, and this routine ends.
[0086]
[Shift time constant setting process in manual mode]
FIG. 6 is a flowchart showing a shift time constant setting process in the manual mode in the shift control program. This process is executed by the shift time constant calculation unit 74 (FIG. 3).
[0087]
First, at step 104, it is determined whether or not the manual mode is selected in which the fixed gear ratio is manually selected from among the six gears based on whether or not a manual range signal is output from the inhibitor switch 60 (FIG. 2). In the case of, the process proceeds to step 105 (corresponding to a manual mode determination means). Note that, although not shown, when the select lever is tilted to the left from the D range of the H-type shift gate, the mode is switched to the manual mode (the inhibitor switch 60 is activated). When it is moved backward (-side), the shift down is performed (the UP / DOWN switch 69 is actuated), and the shift operation can be performed while the accelerator pedal is depressed.
[0088]
In step 105, the deviation Eip is calculated by subtracting the target gear ratio Ratio0 calculated in the previous routine from the attained gear ratio i ^* at the next gear position by manual operation, and the process proceeds to step 106 (speed ratio deviation calculating means). ).
[0089]
Here, the attained gear ratio i ^* is obtained based on the UP / DOWN information from the UP / DOWN switch 69 to determine the next gear position, and based on the vehicle speed VSP and the gear line corresponding to the next gear position in the shift map shown in FIG. The input rotation speed Ni ^* is searched for and obtained, and the arrival input rotation speed Ni ^* is divided by the transmission output rotation speed No. Further, the target speed ratio Ratio0 is such that the attained speed ratio i ^* at the speed before the speed change is realized with the speed response determined by the first speed time constant Tg1 and the second speed time constant Tg2 which are already set. Is calculated.
[0090]
In step 106, a first shift time constant Tg1 and a second shift time constant Tg2 that determine the shift speed in the shift control are set according to the deviation Eip calculated in step 105, and the process proceeds to step 107 (shift time constant setting means). Equivalent).
[0091]
The first shift time constant Tg1 and the second shift time constant Tg2 are determined by the deviation Eip so that a shift response in which the time t required for the first-stage shift by manual operation becomes a fixed time determined by the type of shift or the like is obtained. Is set according to the size of.
[0092]
In step 107, it is determined whether or not the deviation absolute value | Eip | is equal to or greater than a threshold value A that is greater than the shift deviation at the time of each one-step shift. If YES, the process proceeds to steps 108 to 110 In the case of NO, the first shift time constant Tg1 and the second shift time constant Tg2 set in step 106 are directly used as shift time constants (corresponding to a continuous shift operation time determining means).
[0093]
At step 108, the correction coefficient K0 is obtained by multiplying the deviation absolute value | Eip | by the output rotational speed No (or the vehicle speed VSP) at that time.
[0094]
In step 109, the first shift time constant Tg1 is multiplied by the correction coefficient K0 to calculate a first shift time constant correction value Tg1 ', and the second shift time constant Tg2 is multiplied by the correction coefficient K0 to calculate the second shift time constant Tg1'. The correction value Tg2 'is calculated.
[0095]
In step 110, the first shift time constant correction value Tg1 'is set as the first shift time constant Tg1, and the second shift time constant correction value Tg2' is set as the second shift time constant Tg2.
[0096]
Steps 108 to 110 correspond to the shift time constant correcting means according to the third aspect.
[0097]
Therefore, for example, in the shift in the manual mode, after the 4 → 3 shift operation (first shift operation), the 3 → 2 shift operation (second shift operation) before the actual speed ratio reaches the speed ratio corresponding to the third speed. ) (See FIG. 7), the flow proceeds to step 104 → step 105 → step 106 → step 107 → step 108 → step 109 → step 110 in the flowchart of FIG. 6, and is corrected to the first shift time constant Tg1. The first shift time constant correction value Tg1 'obtained by multiplying the coefficient K0 is set as the first shift time constant Tg1, and the second shift time constant correction value Tg2' obtained by multiplying the second shift time constant Tg2 by the correction coefficient K0 is obtained. A correction is made to a value larger than the shift time constants Tg1 and Tg2 obtained in step 106, that is, a correction to reduce the shift speed is made to be a two-shift time constant Tg2.
[0098]
That is, as shown in FIG. 8, the time required to reach the final M2 speed is high in the conventional case at time t from the 3 → 2 speed change operation, whereas in the present embodiment, the time required to reach the final M2 speed is → Time T (> t) has elapsed since the two-gear shift operation, and the gear shift speed is reduced.
[0099]
As a result, the shift speed is reduced by correcting the shift time constants Tg1 and Tg2 during the continuous shift operation in the manual mode, so that the inertia torque determined by the change in the output rotation of the transmission acts on each component of the transmission. It is possible to prevent the influence of slip and the like.
[0100]
In the determination at the time of the continuous gear shifting operation in step 107, the deviation absolute value | Eip |, which is the absolute value of the difference between the current target gear ratio Ratio0 and the attained gear ratio i ^* after the gear shifting operation, is determined for each single-gear shift. When the shift time is larger than the threshold value A, which is larger than the shift time deviation, it is determined that a continuous shift operation is being performed. Therefore, the difference Eip, which is setting information of the shift time constants Tg1 and Tg2, is used as a criterion. It is possible to accurately judge the time of the continuous shift operation while using the easy judgment method used.
[0101]
Further, in the shift time constant correction processing in steps 108 to 110, the correction coefficient K0 of the inertia-equivalent variable calculated based on the deviation absolute value | Eip | calculated in step 105 and the output rotation speed No of the transmission at that time. Is larger, the shift time constants Tg1 and Tg2 are variably set to a larger value, so that the shift time constant is corrected to slow down the shift speed. Therefore, an element of the output rotation speed No that can estimate the magnitude of the inertia torque is taken in. By correcting the shift time constants Tg1 and Tg2, the optimal shift time constant for maintaining the magnitude of the inertia torque acting on each part of the transmission constant during continuous shift operation regardless of the driving condition or running condition. Corrections can be made.
[0102]
The present invention is not limited to the above embodiment, and many modifications and variations are possible.
[0103]
For example, in the above-described embodiment, a case has been described in which the transmission control device of the continuously variable transmission according to the present invention is applied to a toroidal type continuously variable transmission. However, the transmission control device of the present invention is applied to a V-belt type continuously variable transmission. It can also be applied.
[0104]
Further, in the above-described embodiment, the example in which the speed ratio deviation is obtained from the difference between the target speed ratio at the present time and the attained speed ratio after the speed change has been described. It may be a ratio.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional side view of a toroidal type continuously variable transmission including a shift control device for a continuously variable transmission according to the present invention.
FIG. 2 is a vertical sectional front view showing the toroidal-type continuously variable transmission shown in FIG. 1 together with a shift control system thereof.
FIG. 3 is a functional block diagram of a shift control executed by a controller of FIG. 2;
FIG. 4 is a shift diagram illustrating a shift pattern of the continuously variable transmission.
FIG. 5 is a flowchart showing the entire shift control program of the shift control device for the continuously variable transmission according to the present invention.
FIG. 6 is a flowchart showing a shift time constant setting process in a manual mode in a shift control program.
FIG. 7 is a diagram showing a shift map used in a manual mode.
FIG. 8 is a time chart showing an attained speed ratio characteristic and a target speed ratio characteristic when a continuous speed change operation of 4 → 3 → 2 is performed by the speed change time constant setting method according to the embodiment.
FIG. 9 is a time chart showing an attained speed ratio characteristic and a target speed ratio characteristic when a speed change operation of 3 → 2 is performed after reaching a speed ratio of 3rd speed after a 4 → 3 speed change operation.
FIG. 10 is a time chart showing an attained speed ratio characteristic and a target speed ratio characteristic when a continuous speed change operation of 4 → 3 → 2 is performed by a conventional speed change time constant setting method.
[Explanation of symbols]
Reference Signs List 1 input cone disc 2 output cone disc 3 power roller 4 step motor 5 shift control valve 6 piston 7 precess cam 8 shift link 20 input shaft 28 loading cam 41 trunnion 43 upper link 45 lower link 60 inhibitor switch 61 controller 62 throttle opening sensor 63 Vehicle speed sensor 64 input rotation sensor 65 output rotation sensor 66 oil temperature sensor 67 line pressure sensor 68 engine rotation sensor 69 UP / DOWN switch 70 mode selection switch 71 shift map selection unit 72 arrival input rotation speed calculation unit 73 arrival speed ratio calculation unit 74 Shift time constant calculator 75 Target gear ratio calculator 310 Engine control switch 320 Anti-skid control device 330 Traction control device 340 Constant-speed traveling device

Claims (3)

In the transmission control device of a continuously variable transmission having a manual mode function in which a fixed speed ratio can be sequentially selected from a plurality of speed stages manually, in addition to a smooth speed change by stepless,
Manual mode determining means for determining whether or not a shift is being performed in the manual mode;
A gear ratio deviation calculating means for calculating a gear ratio deviation between the current gear ratio and the attained gear ratio after the gear change operation during manual mode gear shifting;
Shift time constant setting means for setting a shift time constant necessary for calculating a transient target speed ratio from a steady attained speed ratio according to the magnitude of the calculated speed ratio deviation;
A continuous shifting operation determining means for determining whether or not a continuous shifting operation in which a first shifting operation is performed by a manual shifting operation and then a second shifting operation is performed before the actual speed ratio reaches the attained speed ratio after shifting. When,
Shift time constant correction means for correcting the shift time constant set by the shift time constant setting means to reduce the shift speed when it is determined that the shift time is being operated;
A shift control device for a continuously variable transmission, comprising: The shift control device for a continuously variable transmission according to claim 1,
The continuous gear shifting operation determining means determines that the gear ratio deviation absolute value, which is the absolute value of the difference between the current gear ratio and the attained gear ratio after the gear shifting operation, is greater than the gear ratio deviation during each single-gear shift. A shift control device for a continuously variable transmission, wherein the shift control device is configured to determine that a continuous shift operation is being performed when the shift is larger than a set threshold value. The shift control device for a continuously variable transmission according to claim 2,
The shift time constant correcting means is configured to decrease the shift speed as the absolute value of the gear ratio deviation calculated by the continuous shift operation determining means and the inertia-equivalent variable calculated from the transmission output rotation speed at that time are larger. A shift control device for a continuously variable transmission, wherein a shift time constant is corrected by setting.

Images