JP3572608B2 - Transmission control device for continuously variable transmission - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a shift control device for a continuously variable transmission applied to a vehicle equipped with a slip control device such as an anti-skid control device (ABS) or a traction control device (TCS) and a continuously variable transmission. Belongs to.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, as a shift control device of a vehicle equipped with both an anti-lock brake device and a continuously variable transmission, for example, a shift control device described in Japanese Patent Application Laid-Open No. H2-234851 is known.
[0003]
According to this publication, when an anti-lock brake device is operating, a drive wheel vehicle speed fluctuates due to an increase or decrease in a braking force. Therefore, in the shift control in which the driving wheel vehicle speed is set as the shift control vehicle speed, useless shift control in which the gear ratio suddenly changes to the deceleration side is performed.
[0004]
Therefore, in order to prevent the anti-lock effect of the anti-lock brake device from being deteriorated by the shift control, when the anti-lock brake device is operating, the drive wheel speed, which is the shift control vehicle speed for determining the shift target value, is reduced. A technique for replacing the estimated vehicle speed with the estimated vehicle speed is shown.
[0005]
[Problems to be solved by the invention]
However, in the conventional shift control device for a continuously variable transmission, when the anti-lock brake control ends and the anti-lock brake device is switched from the operating state to the non-operating state, the shift control vehicle speed of the shift control is immediately set. Is returned from the estimated vehicle speed to the drive wheel speed, and when returning to the drive wheel speed, if the difference between the estimated vehicle speed and the drive wheel speed is large such as when the drive wheels are still slipping, the shift control vehicle speed changes suddenly. Accordingly, there is a problem that the gear ratio also changes suddenly, and a shock or a re-slip may occur.
[0006]
SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and prevents a sudden change in the gear ratio at the end of the operation of the slip control device while preventing deterioration of the braking / driving force control performance due to unnecessary speed change immediately after the start of the operation of the slip control device. It is an object of the present invention to provide a shift control device for a continuously variable transmission that suppresses the occurrence of shock, re-slip, and the like by suppressing the occurrence of shocks and re-slip.
[0007]
[Means for Solving the Problems]
According to the first aspect of the present invention, a slip control device that controls at least one of a braking force and a driving force acting between a tire and a road surface, and a drive wheel that continuously changes input rotation from an engine to drive wheels. And a continuously variable transmission that obtains output rotation to the vehicle,
Shift control means for setting a running state including at least a shift control vehicle speed of the vehicle as an input, and setting an input rotational speed or a gear ratio after the shift of the continuously variable transmission,
Operating state determining means for determining an operating state of the slip control device;
When the slip control device is not operated by the operation state determining means, a shift control vehicle speed based on a vehicle speed sensor vehicle speed which is a driving wheel speed is input to the shift control device, and when the slip control device is operated. Is a shift control device for a continuously variable transmission that inputs a shift control vehicle speed based on an estimated vehicle speed used for braking / driving force control to the shift control means.
Shift control vehicle speed switching means for switching the shift control vehicle speed from the vehicle speed sensor vehicle speed to the estimated vehicle body speed at the same time as the switching determination when the slip control device determines to switch from non-operation to operation;
When the slip control device determines to switch from operation to non-operation, the estimated vehicle speed and the vehicle speed sensor vehicle speed are monitored, and the gear ratio change caused by returning the shift control vehicle speed from the estimated vehicle body speed to the vehicle speed sensor vehicle speed is within the allowable change range. Return condition determination means for determining a return condition set based on a determination criterion that
When the return condition is satisfied, a shift control vehicle speed return unit that returns the shift control vehicle speed from the estimated vehicle speed to the vehicle speed sensor vehicle speed,
It is characterized by having.
[0008]
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 return condition determination means determines the absolute value of the difference between the input speed or gear ratio after the shift calculated using the estimated vehicle speed and the input speed or gear ratio after the shift calculated using the vehicle speed sensor vehicle speed. A means for determining whether the value is equal to or less than a set threshold value is provided.
[0009]
According to a third aspect of the present invention, in the shift control device for a continuously variable transmission according to the first or second aspect,
Providing vehicle speed determination means for determining whether the estimated vehicle speed is equal to or less than a fixed value set as the minimum value of the shift control vehicle speed,
Even if the return condition is not satisfied, if the estimated vehicle speed is determined to be equal to or less than the fixed value, the shift control vehicle speed is changed from the estimated vehicle speed to the vehicle speed sensor vehicle speed. It is characterized by a means for returning.
[0010]
Function and Effect of the Invention
According to the first aspect of the present invention, in the shift control means of the continuously variable transmission for continuously changing the input rotation from the engine to obtain the output rotation to the drive wheels, at least the shift control of the vehicle is performed. The running state including the vehicle speed is input, and the input rotation speed or the gear ratio of the continuously variable transmission after the shift is set.
[0011]
In this shift control, the operating state determining means determines the operating state of the slip control device that controls at least one of the braking force and the driving force acting between the tire and the road surface.
[0012]
If it is determined by the operating state determining means that the slip control device is not operating, a shift control vehicle speed based on a vehicle speed sensor vehicle speed, which is a driving wheel speed, is input to the shift control device, and the input rotation speed after shifting or The gear ratio is set. On the other hand, when it is determined by the operating state determining means that the slip control device is operating, a shift control vehicle speed based on the estimated vehicle speed used for braking / driving force control is input to the shift control means, and the input rotation after the shift is changed. A number or gear ratio is set.
[0013]
When it is determined that the slip control device is switched from non-operation to operation, the transmission control vehicle speed switching means switches the transmission control vehicle speed from the vehicle speed sensor vehicle speed to the estimated vehicle body speed simultaneously with the switching determination.
[0014]
On the other hand, when the slip control device determines to switch from operation to non-operation, the return condition determination means monitors the estimated vehicle speed and the vehicle speed sensor vehicle speed, and shifts by shifting the shift control vehicle speed from the estimated vehicle body speed to the vehicle speed sensor vehicle speed. A return condition set based on a criterion that the ratio change is within an allowable change range is determined. When the return condition is satisfied, the shift control vehicle speed returning means changes the shift control vehicle speed from the estimated vehicle speed to the vehicle speed sensor vehicle speed. Is returned to.
[0015]
As described above, when the operation of the slip control device is started, the shift control vehicle speed is immediately switched from the vehicle speed sensor vehicle speed to the estimated vehicle body speed, so that the vehicle speed sensor vehicle speed is set to the shift control vehicle speed even in the operation state of the slip control device. Unnecessary shifting as in the case described above is suppressed, and deterioration of braking / driving force control performance due to unnecessary shifting immediately after the start of operation of the slip control device is prevented. Here, the deterioration of the braking / driving force control performance means, for example, that when the anti-skid control device is activated, the braking force acting on the wheels is excessively increased due to the sudden change in the gear ratio in the deceleration side in addition to the braking force due to the brake fluid pressure. It means that braking lock is caused early.
[0016]
Further, when the operation of the slip control device is completed, the speed change control vehicle speed is not immediately returned from the estimated vehicle speed to the vehicle speed sensor vehicle speed, but is returned based on the determination criterion that the speed ratio change is within the allowable change range. After the condition is satisfied, the shift control vehicle speed is returned from the estimated vehicle speed to the vehicle speed sensor vehicle speed. Therefore, when the operation of the slip control device ends, a sudden change in the gear ratio is reliably suppressed, and when the operation of the slip control device is terminated, the shock caused by the sudden change in the gear ratio, such as when the speed control vehicle speed is returned to the vehicle speed sensor vehicle speed. The occurrence of re-slip or the like is prevented.
[0017]
In the invention according to claim 2 of the present invention, the return condition determining means calculates the input speed or the gear ratio after the shift calculated using the estimated vehicle speed and the vehicle speed sensor vehicle speed. When the absolute value of the difference from the input rotation speed or the gear ratio after the gear shift is equal to or less than the set threshold value, it is determined that the return condition is satisfied.
[0018]
In other words, there is a concept that the return to the vehicle speed sensor vehicle speed is permitted by a simple difference between the vehicle speed sensor vehicle speed and the estimated vehicle body speed. It is difficult to set a threshold value, for example, it is necessary to set a large number in accordance with the range or to calculate by a function of the vehicle speed.
[0019]
On the other hand, since the input rotation speed or gear ratio after shifting corresponds to the control target value in the shift control, the target value calculated using the estimated vehicle speed and the target value calculated using the vehicle speed sensor When the return is permitted by the absolute value of the difference between, only one threshold value needs to be set.
[0020]
Therefore, it is possible to set the return condition based on the criterion that the change in the gear ratio is within the allowable change range, while easily setting the threshold value.
[0021]
In the invention according to claim 3 of the present invention, the vehicle speed determining means determines whether or not the estimated vehicle speed is equal to or less than a fixed value set as the minimum value of the shift control vehicle speed, and the shift control vehicle speed returning means. Even when the return condition is not satisfied, if the estimated vehicle speed is determined to be equal to or less than the fixed value by the vehicle speed determination means, the shift control vehicle speed is returned from the estimated vehicle speed to the vehicle speed sensor vehicle speed.
[0022]
That is, in order to suppress unstable shift control in an extremely low speed range where the vehicle speed detection accuracy is low, the minimum value of the shift control vehicle speed is set to a fixed value, and when the vehicle speed becomes lower than that, the shift is changed. The control vehicle speed does not fall below the minimum value, and even if there is a slight difference between the vehicle speed sensor vehicle speed and the estimated vehicle speed, the minimum gear ratio is set near the fixed value vehicle speed. I have.
[0023]
Therefore, if it is determined that the estimated vehicle speed is equal to or lower than the fixed value, a shock or re-slip may occur even if the shift control vehicle speed is immediately returned from the estimated vehicle speed to the vehicle speed sensor speed without waiting for the return condition to be satisfied. And the shift control vehicle speed can be returned to the vehicle speed sensor vehicle speed with good response from the end of the operation of the slip control device.
[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]
An actuator drive position command Asstep to the step motor 4 is determined 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 determines 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 calculator 74 includes a selection range (forward normal travel range D, forward sports travel range Ds), a vehicle speed VSP, a throttle opening TVO, an engine speed Ne, an accelerator pedal operation speed, and a 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. The first shift time constant Tg1 and the second shift time constant Tg2 of the control are determined, and the 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 determined to correspond to the secondary delay system of the toroidal-type continuously variable transmission determine the response of the shift 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 determined 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 determined 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 section 87 determines that the step motor 4 determines the target step number DsrSTP during one control cycle even at the limit drive speed of the step motor 4 determined by the step motor drive speed determination section 88 from the transmission operating oil temperature TMP or 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 determined as described above by the step motor drive speed determination 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 setting unit 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 rotation sensor 68 (FIG. 2), and inputs. 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]
[Setting of shift control vehicle speed]
The above description has been made on the assumption that the ABS or TCS is inactive, and the case where the reaching input rotation speed Ni ^* is obtained using the vehicle speed VSP from the vehicle speed sensor 63 has been described. However, in the present embodiment, the anti-skid control is performed. When an operation signal is input from the device 320 or the traction control device 330, a configuration is adopted in which the estimated vehicle speed VSPFL is set as the shift control vehicle speed SftVSP instead of the vehicle speed VSP from the vehicle speed sensor 63 (hereinafter, vehicle speed sensor vehicle speed VSPSEN). ing.
[0087]
FIG. 6 is a flowchart showing a shift control vehicle speed setting process in the shift control program. This process is executed by the reaching input rotation speed calculation unit 72 (FIG. 3).
[0088]
First, in step 104, it is determined whether or not the ABS is operating based on the operation signal from the anti-skid control device 320 (corresponding to an operating state determining means). When it is determined that the operation is not performed, the process proceeds to step 105, and when it is determined that the operation is performed, the process proceeds to step 107.
[0089]
In step 105, it is determined whether or not the operation is the TCS operation based on the operation signal from the traction control device 330 (corresponding to the operation state determining means). If it is determined that it is not operating, the process proceeds to step 106, and if it is determined that it is operating, the process proceeds to step 107.
[0090]
In step 106, a vehicle speed sensor vehicle speed VSPSEN from the vehicle speed sensor 63 for detecting the driving wheel speed is set as the shift control vehicle speed SftVSP, and the process returns to step 104.
[0091]
In step 107, the estimated vehicle speed VSPFL is set as the shift control vehicle speed SftVSP, and the routine proceeds to step 108. Here, the estimated vehicle speed VSPFL refers to a vehicle speed calculation value obtained by integrating a pseudo vehicle speed determined based on a driven wheel speed by ABS control or TCS control or an output signal from a longitudinal acceleration sensor.
[0092]
Steps 104 to 107 correspond to a shift control vehicle speed switching means of the first aspect.
[0093]
In step 108, it is determined whether or not the ABS operation is performed based on the operation signal from the anti-skid control device 320 (corresponding to an operation state determination unit). When it is determined that the operation is not performed, the process proceeds to step 109, and when it is determined that the operation is performed, the process proceeds to step 107.
[0094]
In step 109, it is determined whether or not the operation is the TCS operation based on the operation signal from the traction control device 330 (corresponding to the operation state determining means). When it is determined that the operation is not performed, the process proceeds to step 110, and when it is determined that the operation is performed, the process proceeds to step 107.
[0095]
In step 110, the reached input rotational speed Ni ^* FL is calculated from the throttle opening TVO and the estimated vehicle speed VSPFL based on the shift map as shown in FIG. 4, and based on the throttle opening TVO and the vehicle speed sensor vehicle speed VSPSEN. Based on the shift map as shown in FIG. 4, the reached input rotation speed Ni ^* SEN is calculated, and the routine proceeds to step 111.
[0096]
In step 111, the absolute value of the difference between the reached input rotation speed Ni ^* FL calculated using the estimated vehicle speed VSPFL and the reached input rotation speed Ni ^* SEN calculated using the vehicle speed sensor vehicle speed VSPSEN is set. It is determined whether the value is equal to or less than the threshold value A (corresponding to a return condition determining means). Here, in the case where the gear ratio changes by returning the gearshift control vehicle speed SftVSP from the estimated vehicle body speed VSPFL to the vehicle speed sensor vehicle speed VSPSEN, a maximum value that allows the occupant to allow the gear ratio change is determined by an experiment or the like. The value is set as the set threshold value A. When YES is determined in this step 111, the process proceeds to step 106, where the shift control vehicle speed SftVSP is returned from the estimated vehicle speed VSPFL to the vehicle speed sensor vehicle speed VSPSEN (corresponding to a shift control vehicle speed returning means of claim 1). If NO is determined in step 111, the process proceeds to step 112.
[0097]
In step 112, it is determined whether or not the estimated vehicle speed VSPFL is equal to or less than the fixed value B (corresponding to a vehicle speed determining means). Here, the value set as the minimum value of the shift control vehicle speed SftVSP is the fixed value B. When YES is determined in this step 112, the process proceeds to step 106, where the shift control vehicle speed SftVSP is returned from the estimated vehicle speed VSPFL to the vehicle speed sensor vehicle speed VSPSEN (corresponding to a shift control vehicle speed returning means of claim 3). If NO is determined in step 112, the process proceeds to step 107.
[0098]
Therefore, when the vehicle is running in which neither the ABS nor the TCS is in operation, the flow of step 104 → step 105 → step 106 is repeated in the flowchart of FIG. 6, and in step 106, the vehicle speed sensor vehicle speed VSPSEN is set as the shift control vehicle speed SftVSP. Will be maintained.
[0099]
When the ABS or the TCS starts to operate from the non-operation state of the ABS and the TCS, the flow of step 104 → step 107 or step 104 → step 105 → step 107 in the flowchart of FIG. 6, and in step 107, the shift control vehicle speed SftVSP Is switched from the vehicle speed sensor vehicle speed VSPSEN to the estimated vehicle body speed VSPFL.
[0100]
While the ABS or TCS is operating, the flow of FIG. 6 repeats Step 107 → Step 108 or Step 107 → Step 108 → Step 109, and the estimated vehicle speed VSPFL in Step 107 is Will be maintained.
[0101]
When the operation of the ABS or the TCS is completed and both the ABS and the TCS are deactivated, the flow proceeds to step 107 → step 108 → step 109 → step 110 → step 111 in the flowchart of FIG. A return condition is determined in which the absolute value of the difference between the attained input rotational speed Ni ^* FL and the attained input rotational speed Ni ^* SEN is equal to or less than the set threshold value A. If the return condition is not satisfied, the process proceeds to step 107 via step 112. Returning, the flow of the above steps is repeated until the return condition is satisfied. When the return condition in step 111 is satisfied, the process proceeds from step 111 to step 106, where the shift control vehicle speed SftVSP is returned from the estimated vehicle body speed VSPFL to the vehicle speed sensor vehicle speed VSPSEN.
[0102]
Further, even if the return condition in step 111 is not satisfied, if the vehicle speed condition that the estimated vehicle speed VSPFL is equal to or lower than the fixed value B is satisfied, the process proceeds from step 112 to step 106, and the shift control vehicle speed SftVSP is reduced to the estimated vehicle speed VSPFL. Is returned to the vehicle speed sensor vehicle speed VSPSEN.
[0103]
As described above, according to the present embodiment, when the operation of the ABS or TCS is started, the shift control vehicle speed SftVSP is immediately switched from the vehicle speed sensor vehicle speed VSPSEN to the estimated vehicle body speed VSPFL. Unnecessary shifts such as when the vehicle speed sensor is used as the shift control vehicle speed in the operating state are suppressed, and deterioration of the ABS control performance or TCS control performance due to unnecessary shifts immediately after the start of the ABS or TCS operation is prevented. Further, upon completion of the operation of the ABS or TCS, the speed change control vehicle speed SftVSP is not immediately returned from the estimated vehicle speed VSPFL to the vehicle speed sensor vehicle speed VSPSEN, but is set based on a determination criterion that the speed ratio change is within the allowable change range. After the established return condition is satisfied, the shift control vehicle speed SftVSP is returned from the estimated vehicle body speed VSPFL to the vehicle speed sensor vehicle speed VPSEN, so that a sudden change in the gear ratio at the end of the operation of the ABS or the TCS is reliably suppressed, and the ABS or the As in the case where the shift control vehicle speed SftVSP is returned to the vehicle speed sensor vehicle speed VSPSEN at the same time as the end of the operation of the TCS, the occurrence of a shock or a re-slip due to a sudden change in the gear ratio is prevented.
[0104]
In determining the return condition, the absolute value of the difference between the reached input rotation speed Ni ^* FL calculated using the estimated vehicle speed VSPFL and the reached input rotation speed Ni ^* SEN calculated using the vehicle speed sensor vehicle speed VSPSEN is determined. If the value is equal to or less than the set threshold value A, it is determined that the return condition is satisfied. Therefore, setting of one threshold value is easy and setting of the threshold value is easy, but the change of the gear ratio is an allowable change. It is possible to set a return condition based on the criterion of being within the range.
[0105]
In other words, it is possible to allow the vehicle speed sensor to return to the vehicle speed sensor VSPSEN with a simple difference between the vehicle speed sensor vehicle speed VSPSEN and the estimated vehicle body speed VSPFL. It is difficult to set a threshold value, for example, it is necessary to set a large number of values corresponding to the vehicle speed range, or to calculate by a function of the vehicle speed.
[0106]
Further, even when the return condition is not satisfied, if it is determined that the estimated vehicle speed VSPFL is equal to or lower than the fixed value B, the shift control vehicle speed SftVSP is returned from the estimated vehicle speed VSPFL to the vehicle speed sensor vehicle speed VSPSEN, so that a shock or The shift control vehicle speed SftVSP can be returned to the vehicle speed sensor vehicle speed VPSEN with good response from the end of the operation of the ABS or TCS while preventing occurrence of re-slip or the like.
[0107]
That is, the minimum value of the shift control vehicle speed SftVSP is set to the fixed value B in order to suppress unstable shift control in an extremely low speed range where the vehicle speed detection accuracy is low, and when the estimated vehicle speed VSPFL becomes lower than that, The shift control vehicle speed SftVSP does not fall below the minimum value. Even when there is a slight difference between the vehicle speed sensor vehicle speed VSPSEN and the estimated vehicle body speed estimated vehicle speed VSPFL, the vehicle speed near the fixed value B is the lowest. The gear ratio is set.
[0108]
The present invention is not limited to the above embodiment, and many modifications and variations are possible.
[0109]
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.
[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 control vehicle speed setting process in a shift control program.
[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)

A slip control device that controls at least one of a braking force and a driving force acting between a tire and a road surface, and a continuously variable transmission that continuously changes an input rotation from an engine to obtain an output rotation to a driving wheel. A mounted vehicle,
Shift control means for setting a running state including at least a shift control vehicle speed of the vehicle as an input, and setting an input rotational speed or a gear ratio after the shift of the continuously variable transmission;
Operating state determining means for determining an operating state of the slip control device;
When the slip control device is not operated by the operation state determining means, a shift control vehicle speed based on a vehicle speed sensor vehicle speed which is a driving wheel speed is input to the shift control device, and when the slip control device is operated. Is a shift control device for a continuously variable transmission that inputs a shift control vehicle speed based on an estimated vehicle speed used for braking / driving force control to the shift control means.
Shift control vehicle speed switching means for switching the shift control vehicle speed from the vehicle speed sensor vehicle speed to the estimated vehicle body speed at the same time as the switching determination when the slip control device determines switching from non-operation to operation;
When the slip control device determines to switch from operation to non-operation, the estimated vehicle speed and the vehicle speed sensor vehicle speed are monitored, and the gear ratio change caused by returning the shift control vehicle speed from the estimated vehicle body speed to the vehicle speed sensor vehicle speed is within the allowable change range. Return condition determination means for determining a return condition set based on a determination criterion that
When the return condition is satisfied, a shift control vehicle speed return unit that returns the shift control vehicle speed from the estimated vehicle speed to the vehicle speed sensor vehicle speed,
A shift control device for a continuously variable transmission, comprising: The shift control device for a continuously variable transmission according to claim 1,
The return condition determination means determines the absolute value of the difference between the input speed or gear ratio after shifting calculated using the estimated vehicle speed and the input speed or gear ratio after shifting calculated using the vehicle speed sensor vehicle speed. A shift control device for a continuously variable transmission, wherein a means for determining whether a value is equal to or less than a set threshold value is provided. The shift control device for a continuously variable transmission according to claim 1 or 2,
Providing a vehicle speed determining means for determining whether the estimated vehicle speed is equal to or less than a fixed value set as a minimum value of the shift control vehicle speed,
Even if the return condition is not satisfied, if the estimated vehicle speed is determined to be less than or equal to the fixed value, the shift control vehicle speed is changed from the estimated vehicle speed to the vehicle speed sensor vehicle speed. A shift control device for a continuously variable transmission, wherein the shift control device is a returning unit.

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