JP3561907B2 - 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 automatic upshift control of a vehicle equipped with both a traction control device (TCS) and a continuously variable transmission having a manual mode function.
[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 discloses that in a continuously variable transmission having a manual mode function in which a fixed gear ratio can be sequentially selected from a plurality of gear positions by manual operation, when shifting in the manual mode, the engine speed exceeds an upper limit value. A device is disclosed that automatically shifts up to prevent over-rev of the engine.
[0004]
[Problems to be solved by the invention]
However, in the overrev prevention control in the conventional shift control device for a continuously variable transmission, the control for automatically shifting up when the engine speed exceeds the upper limit even during the TCS operation is performed. There has been a problem that the shift inertia increases with the upshift, and the TCS performance for suppressing excessive drive torque may deteriorate.
[0005]
On the other hand, since the tire slip occurs during the TCS operation, there is a proposal that the threshold value for automatically shifting up is set uniformly low.
[0006]
However, the change in the driving torque due to the over-rev prevention control is determined by the amount of change in the gear ratio due to the upshift and the magnitude of the shift inertia based on the transmission output rotation speed. The lower the speed, the greater the shift inertia. Therefore, when the threshold value is set uniformly low, if the threshold is set at a level slightly lower than the upper limit in order to secure the TCS performance on the high speed side, the shift inertia becomes large on the low speed side and the TCS performance cannot be secured. Conversely, if the setting is made at a rather low level away from the upper limit in order to secure the TCS performance at the low speed stage, useless auto-up is frequently performed at the high speed stage even though the engine is not overspeeding. Will be performed.
[0007]
The present invention has been made in view of the above problems, and sets a driving force control correspondence threshold separately in the manual mode, when the driving force control device is operating, and when the driving force control device is not operating. Accordingly, it is an object of the present invention to provide a shift control device for a continuously variable transmission that achieves both prevention of engine overrev and securing of driving force control performance at all shift speeds from a low speed to a high speed.
[0008]
[Means for Solving the Problems]
According to the first aspect of the present invention, a driving force control device that controls a driving force that acts between a tire and a road surface, and a manual mode function that allows a fixed gear ratio to be sequentially selected from a plurality of gears by manual operation. In order to prevent over-rev in manual mode, when the detected engine speed equivalent value exceeds the auto-up rotation threshold value set in the maximum speed range, it is automatically installed. In a shift control device for a continuously variable transmission including an overrev prevention control unit for shifting up,
Operating state determining means for determining an operating state of the driving force control device;
Instead of the auto-up rotation threshold set in the maximum rotation speed range, a threshold for setting the driving force control threshold set in the low rotation speed range on the low speed side and in the high rotation speed range on the high speed side. Value setting means;
In manual mode and when the driving force control device is activated, the driving force that automatically shifts up when the detected engine speed equivalent value is equal to or greater than the driving force control corresponding threshold value determined by the gear position determination. Control corresponding control means,
Is provided.
[0009]
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 threshold value setting means is characterized in that a threshold value corresponding to the driving force control based on a lower rotational speed is set for each shift speed as the shift speed is lower.
[0010]
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 threshold value setting means is a variable setting means for setting a threshold value corresponding to the driving force control to a lower rotation speed as a variable corresponding to a shift ratio change amount due to an upshift and a transmission inertia equivalent variable based on a transmission output rotation speed is larger. It is characterized by.
[0011]
Function and Effect of the Invention
According to the first aspect of the present invention, in the manual mode, a fixed gear ratio is sequentially selected from a plurality of gear positions by manual operation. If the engine overspeeds during this manual mode and the detected engine speed equivalent value becomes equal to or greater than the auto-up rotation threshold value set in the maximum speed range, the overrev prevention control means performs manual operation for shifting. Even if not performed, the upshift is automatically performed, and the upshift reduces the value corresponding to the engine speed (such as the engine speed and the input speed of the transmission), thereby preventing overrev.
[0012]
On the other hand, in the manual mode, the operating state determining means determines the operating state of the driving force control device that controls the driving force acting between the tire and the road surface. When the driving force control correspondence threshold value determined by the determination is equal to or greater than the threshold value, the driving force control correspondence control means automatically shifts up. Here, the threshold value corresponding to the driving force control is replaced with an auto-up rotation threshold value when the driving force control device is not operated, which is set in the maximum rotation speed range, by the threshold value setting means. The high speed range is set to a high rotational speed range in several ranges.
[0013]
Therefore, in the manual mode, when the driving force control device is operating, and when the driving force control device is not operating, the driving force control corresponding threshold value is set separately. By setting the speed range to the low speed range and the high speed range to the high speed range, overspeed prevention and driving force of the engine are prevented at all speed stages from the low speed stage with large shift inertia to the high speed stage with small shift inertia. The control performance can be ensured.
[0014]
In the invention according to claim 2 of the present invention, the threshold value setting means sets a driving force control corresponding threshold value with a lower rotational speed for each shift speed as the shift speed is lower. Have been.
[0015]
Therefore, by setting the driving force control corresponding threshold value for each gear position, when the driving force control device starts to operate, it is optimal that both the over-rev prevention and the driving force control performance are well balanced at any gear stage. Threshold value can be set.
[0016]
According to the third aspect of the present invention, in the threshold value setting means, the larger the variable corresponding to the shift inertia due to the shift ratio change amount due to the upshift and the transmission output rotation speed, the greater the driving force control. The threshold value corresponding to the driving force control is set by the variable setting for setting the threshold value to a low rotation speed.
[0017]
Therefore, by setting the threshold value variably on the basis of the shift inertia at which the driving force control performance is ensured, the driving force control performance can be ensured by a substantially constant shift inertia irrespective of the driving condition or the running condition. .
[0018]
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.
[0019]
[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.
[0020]
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.
[0021]
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.
[0022]
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.
[0023]
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.
[0024]
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.
[0025]
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.
[0026]
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.
[0027]
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.
[0028]
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.
[0029]
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.
[0030]
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.
[0031]
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.
[0032]
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.
[0033]
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.
[0034]
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.
[0035]
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.
[0036]
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.
[0037]
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.
[0038]
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.
[0039]
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.
[0040]
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.
[0041]
The actuator drive position command Asstep to the step motor 4 is set by the controller 61.
[0042]
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.
[0043]
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.
[0044]
[Controller configuration]
In the present embodiment, the controller 61 is configured as shown in FIG.
[0045]
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.
[0046]
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.
[0047]
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.
[0048]
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.
[0049]
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.
[0050]
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.
[0051]
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.
[0052]
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.
[0053]
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.
[0054]
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.
[0055]
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.
[0056]
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.
[0057]
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.
[0058]
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.
[0059]
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).
[0060]
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.
[0061]
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.
[0062]
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.
[0063]
Accordingly, the drive position command Asstep can always be regarded as the actual drive position of the step motor 4.
[0064]
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.
[0065]
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.
[0066]
In the present embodiment, a step motor follow-up determination section 89 is additionally provided.
[0067]
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.
[0068]
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.
[0069]
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.
[0070]
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.
[0071]
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.
[0072]
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.
[0073]
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.
[0074]
[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.
[0075]
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.
[0076]
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.
[0077]
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.
[0078]
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.
[0079]
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.
[0080]
[Automatic shift-up control in manual mode]
FIG. 6 is a flowchart showing the automatic upshift control processing in the manual mode in the shift control program.
[0081]
First, at step 104, it is determined whether or not a manual mode is selected in which a fixed gear ratio is selected from six gears by manual operation, based on whether or not a manual range signal is output from the inhibitor switch 60 (FIG. 2). If YES, the process proceeds to step 105.
[0082]
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 actuated). When it is moved backward (negative side), the downshift is performed (the UP / DOWN switch 69 operates).
[0083]
In step 105, it is determined whether or not the TCS is operating (ON signal) based on a signal from the traction control device 330. If NO, the process proceeds to step 106, and if YES, the process proceeds to step 108 (corresponding to an operation state determining means).
[0084]
In step 106, it is determined whether or not the input rotation speed Ni from the input rotation sensor 64 is equal to or greater than the auto-up rotation threshold value NiMAX (see FIG. 7) set in the maximum rotation speed range. If NO, return to step 104 without upshifting.
[0085]
In step 107, the gear is automatically shifted up by one gear from the current gear. Steps 105 to 107 correspond to overrev prevention control means.
[0086]
In step 108, if it is determined in step 105 that the TCS operation is being performed, the current gear position is determined based on the switch signal from the UP / DOWN switch 69, and the process proceeds to step 109.
[0087]
In step 109, as the shift speed is lower, the TCS corresponding threshold value NiTCS based on the lower rotational speed is set for each shift speed as shown in FIG. 7 (corresponding to threshold value setting means). By reading out the TCS-corresponding threshold value NiTCS of the changed gear, the TCS-corresponding threshold value NiTCS is determined, and the routine proceeds to step 110.
[0088]
In step 110, it is determined whether or not the input rotation speed Ni from the input rotation sensor 64 is equal to or greater than the TCS corresponding threshold NiTCS determined in step 109. If YES, proceed to step 111, and if NO, shift up. The process returns to step 104 without any processing.
[0089]
In step 111, the gear is automatically shifted up by one gear from the current gear. Steps 105 to 111 correspond to the driving force control corresponding control means.
[0090]
Therefore, in the manual mode and when the TCS is not operated, the flow proceeds to step 104 → step 105 → step 106 in the flowchart of FIG. When Ni (equivalent value of the engine speed) becomes equal to or higher than the auto-up rotation threshold value NiMAX set in the maximum speed range, the process proceeds from step 106 to step 107, and the automatic operation is performed without performing the manual operation for shifting. , The input speed Ni is reduced, and over-rev is prevented.
[0091]
On the other hand, in the manual mode and at the time of TCS operation, the flow proceeds to step 104 → step 105 → step 108 → step 109 → step 110 in the flowchart of FIG. When the number Ni becomes equal to or greater than the threshold value NiTCS corresponding to the TCS determined by the gear position determination, the process proceeds from step 110 to step 111, and the upshift is automatically performed without performing a manual operation for shifting.
[0092]
Therefore, in the manual mode, and when the TCS is operating and when the TCS is not operating, the TCS-compatible threshold value NiTCS is set separately, and the TCS-compatible threshold value NiTCS is set to a low speed range on the low speed side. By setting the rotational speed in the high rotational speed range, it is possible to achieve both the prevention of the engine over-rev and the securing of the TCS performance at all the shift speeds from the low speed stage where the shift inertia is large to the high speed stage where the shift inertia is small.
[0093]
Further, as the TCS-compatible threshold value NiTCS, the lower the shift speed, the lower the rotational speed, the lower the TCS-compatible threshold value NiTCS is set for each of the shift speeds from manual first speed to manual fifth speed. When the TCS starts to operate, an optimal threshold value can be set at any one of the first to fifth speeds, which can both prevent overrev and ensure TCS control performance.
[0094]
The present invention is not limited to the above embodiment, and many modifications and variations are possible.
[0095]
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.
[0096]
Further, in the above-described embodiment, an example is described in which the input rotation speed of the transmission is used as the engine rotation speed equivalent value, but the engine rotation speed itself may be used as the engine rotation speed equivalent value.
[0097]
Further, in the above-described embodiment, the TCS correspondence threshold is set such that the gear ratios of the respective gears are set substantially at the same ratio, so that, as shown in FIG. Although the example in which the number is set as the threshold value corresponding to the TCS has been described, the threshold value corresponding to the driving force control becomes lower as the variable corresponding to the shift inertia due to the shift ratio change amount due to the upshift and the transmission output rotation speed becomes larger. The threshold value corresponding to the TCS may be set by the variable setting (corresponding to the invention of claim 3).
[0098]
In this case, by setting the threshold value variably based on the shift inertia at which the TCS control performance is ensured, the TCS control performance can be ensured with a substantially constant shift inertia regardless of the driving condition or the running condition.
[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 an automatic upshift control process in a manual mode in a shift control program.
FIG. 7 is a diagram showing a shift map used in a manual mode.
[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 driving force control device that controls the driving force that acts between the tire and the road surface, and a continuously variable transmission that has a manual mode function that allows a fixed gear ratio to be sequentially selected from a plurality of gear positions by manual operation are mounted,
In manual mode, to prevent engine overspeed (hereinafter referred to as overrev), an overrev that automatically shifts up when the detected engine speed equivalent value exceeds the auto-up rotation threshold set in the maximum speed range In a shift control device for a continuously variable transmission provided with prevention control means,
Operating state determining means for determining an operating state of the driving force control device;
Instead of the auto-up rotation threshold set in the maximum rotation speed range, a threshold for setting the driving force control threshold set in the low rotation speed range on the low speed side and in the high rotation speed range on the high speed side. Value setting means;
In manual mode and when the driving force control device is activated, the driving force that automatically shifts up when the detected engine speed equivalent value is equal to or greater than the driving force control corresponding threshold value determined by the gear position determination. Control corresponding control means,
A shift control device for a continuously variable transmission, comprising: The shift control device for a continuously variable transmission according to claim 1,
The said threshold value setting means is a means in which a driving force control corresponding threshold value with a lower rotational speed is set for each shift speed as the shift speed is lower. Transmission control device. The shift control device for a continuously variable transmission according to claim 2,
The threshold value setting means is a variable setting means for setting a threshold value corresponding to the driving force control to a lower rotation speed as a variable corresponding to a shift ratio change amount due to an upshift and a transmission inertia equivalent variable based on a transmission output rotation speed is larger. A shift control device for a continuously variable transmission, characterized by:

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