JP2005090610A - Control device for continuously variable transmission for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control device for a continuously variable transmission for a vehicle, in which operation performance in changeover of speed change modes is improved, and in which a speed change ratio can be properly and speedily changed in accordance with the speed changing intention of a driver. <P>SOLUTION: This control device is provided with a continuously variable automatic speed change mode executing means to execute a continuously variable automatic speed change mode, a stepped automatic speed change mode executing means 3 to execute a stepped automatic speed change mode, changeover operation means 21 and 22 operated to change over the speed change modes in the continuously variable transmission 40, and a speed change mode setting means 3 to set the speed change modes of the continuously variable transmission 40 to either of the continuously variable automatic speed change mode and the stepped automatic speed change mode in accordance with operation states of the changeover operation means. In changeover from the continuously variable automatic speed change mode into the stepped automatic speed change mode by the stepped automatic speed change mode executing means 3, the speed change ratio of the continuously variable transmission 40 is set at the closest value to the speed change ratio set before the changeover in the continuously variable automatic speed change mode till immediately before the changeover among a plurality of prescribed speeds. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a control device for a continuously variable transmission for a vehicle capable of continuously changing the output of an internal combustion engine mounted on the vehicle.

  Conventionally, what was described in patent document 1 is known as a control apparatus of this kind of continuously variable transmission. This control device has an automatic transmission mode in which the gear ratio is automatically set according to the vehicle speed, etc., and the driver himself operates the shift lever so that the driver can perform a driving operation with a stepped feeling. And a manual mode for setting the gear ratio. In this manual mode, one of a plurality of shift speeds is selected according to the operation of the shift lever by the driver, and the gear ratio of the continuously variable transmission is set to a predetermined gear ratio corresponding to the selected gear speed. Is set.

  Further, in this control device, the driver operates the shift lever from the automatic transmission mode side to the manual mode side, so that the transmission mode is switched from the automatic transmission mode to the manual mode. The gear position is increased or decreased to the Hi side or Low side closest to the gear ratio. Such shift change at the time of shifting mode change is set in advance to either upshift or downshift. Therefore, for example, when the shift change at shifting mode change is set to upshift With the operation of the shift lever to the manual mode side, the gear position is always increased. Each time the driver operates the shift lever to the Hi side or the Low side during driving in the manual mode, the gear position is increased or decreased by one step.

  In the continuously variable transmission control device described above, for example, when the shift change at the time of shifting the mode is set to upshift, the driver switches the shifting mode to the manual mode during the automatic shifting mode, When the shift lever is operated to the manual mode side to increase the gear, the gear is automatically increased. However, even if the driver wants to lower the gear position, the gear position is always raised. Therefore, when the gear position is to be lowered, the shift lever is temporarily operated to the manual mode side, and further the shift lever is moved to the low side. A two-stage operation is required. Therefore, this control device has a problem that the gear ratio of the continuously variable transmission cannot be changed quickly according to the driver's intention to shift.

  Of course, by setting the shift change at the time of the shift mode change to downshift in advance, when the driver wants to lower the shift stage, the shift stage can be changed by one operation of the shift lever to the manual mode side. It is possible to bring it down. However, in this case, when the driver wants to increase the gear position, the two-stage operation of the shift lever is required as described above, and the same problem as described above occurs.

  In addition, when the speed change mode is switched from the automatic speed change mode to the manual mode due to an erroneous operation of the driver, the speed ratio of the continuously variable transmission is immediately fixed to a constant speed ratio. The following problems arise. That is, for example, when the engine torque is required, such as when the vehicle is traveling uphill, the engine torque is insufficient when the gear position is increased by the predetermined shift mode setting (upshift setting) as described above. Or when the driver keeps stepping on the accelerator without noticing it when the gear position is lowered due to a predetermined setting of the shift mode (downshift setting) when the vehicle is traveling at high speed, etc. Overlevation occurs, and the speed ratio is fixed as described above and does not match the driver's intention. As a result, drivability is degraded.

  The present invention has been made to solve the above-described problems, and can improve the operability at the time of changing the transmission mode, and appropriately and quickly change the transmission ratio according to the driver's intention to change the transmission. It is an object of the present invention to provide a control device for a continuously variable transmission for a vehicle.

Japanese Patent No. 3218962

  A control device for a continuously variable transmission for a vehicle according to claim 1 of the present invention is a control device 1 for a continuously variable transmission for a vehicle capable of continuously changing the output of an internal combustion engine 2 mounted on a vehicle V. , A driving state detection means for detecting the driving state of the vehicle V (the vehicle speed sensor 12 and the accelerator opening sensor 13 in the embodiment (hereinafter the same in this section)) and the steplessly depending on the detected driving state of the vehicle V Stepless automatic transmission mode execution means (ECU 3, step 24 in FIG. 7) for executing a continuously variable automatic transmission mode (CVT mode) for setting the transmission gear ratio of the transmission 40 steplessly, and the detected driving state of the vehicle V Accordingly, a stepped automatic transmission mode execution means (ECU 3, steps 27 to 27) for executing a stepped automatic transmission mode (AT mode) for setting the gear ratio of the continuously variable transmission 40 to one of a plurality of predetermined gears. 29) and continuously variable transmission 40 Switching operation means (shift stage change switch 22) operated to switch the transmission mode, and the transmission mode of the continuously variable transmission 40 according to the operation state of the switching operation means are set to the continuously variable automatic transmission mode and the stepped automatic transmission. Shift mode setting means (ECU3) for setting one of the shift modes, and the stepped automatic shift mode executing means is a stepless shift at the time of switching the shift mode from the stepless automatic shift mode to the stepped automatic shift mode. The gear ratio of the machine 40 is set to one of a plurality of predetermined gear speeds that is closest to the gear ratio before switching that has been set in the continuously variable automatic transmission mode immediately before switching (steps 32, 42, 52, 72).

  According to this configuration, the continuously variable transmission has the continuously variable automatic transmission mode and the stepped automatic transmission mode as the transmission mode. The transmission mode is determined by the transmission mode setting means according to the operation state of the switching operation means. Thus, one of the two shift modes is set. When the speed change mode of the continuously variable transmission is set to the continuously variable automatic transmission mode, when the switching operation means is operated by the vehicle driver, the transmission mode is changed from the continuously variable automatic transmission mode to the stepped automatic transmission mode. And the gear ratio of the continuously variable transmission is set to one closest to the pre-switching gear ratio among a plurality of predetermined gear speeds. Thus, during the continuously variable automatic transmission mode, the driver can easily switch the transmission mode of the continuously variable transmission to the stepped automatic transmission mode only by operating the switching operation means. Can be quickly set to an appropriate gear position according to the driving state. In addition, for example, even if the shift mode is switched from the continuously variable automatic shift mode to the stepped automatic shift mode due to an erroneous operation of the driver, and the driving state of the vehicle subsequently changes, Since the gear ratio of the transmission is set as appropriate to an appropriate gear position according to the driving state, the engine torque can be ensured without excess or deficiency, and the occurrence of overrevs can be prevented appropriately.

  According to a second aspect of the present invention, in the control device for a continuously variable transmission for a vehicle according to the first aspect, the switching operation means includes an up switch 22a for increasing the shift speed of the continuously variable transmission 40 and a down switch. The stepped automatic transmission mode execution means has a gear ratio of the continuously variable transmission 40 based on the gear ratio before switching when the up switch 22a is operated in the continuously variable automatic transmission mode. Are also set to the high speed side (steps 32 and 52), and when the down switch 22b is operated, the speed ratio of the continuously variable transmission 40 is set to the speed side lower than the pre-switching speed ratio. (Steps 42 and 72).

  According to this configuration, when the driver operates the up switch during the continuously variable automatic transmission mode, the transmission gear ratio of the continuously variable transmission is set to the closest gear position on the high speed side with respect to the gear ratio before switching. On the other hand, by operating the down switch, it is set to the closest gear position on the low speed side with respect to the pre-switching gear ratio. As a result, the shift stage of the continuously variable transmission can be appropriately set in the direction of the shift intended by the driver when performing either the high speed side shift or the low speed side shift.

  According to a third aspect of the present invention, in the control device for a continuously variable transmission for a vehicle according to the first aspect, a rotational speed detecting means (crank angle sensor 11) for detecting the rotational speed of the internal combustion engine 2 (engine rotational speed NE). ) And target rotation speed setting means (ECU3) for setting the target rotation speed NOBJ according to the driving state of the vehicle V for each of a plurality of predetermined shift speeds, and the stepped automatic transmission mode execution means When the shift mode is switched from the continuously variable automatic shift mode to the stepped automatic shift mode, the deviation between the rotational speed of the internal combustion engine 2 and the target rotational speed set for the closest shift speed is less than the first predetermined value. In some cases, the transmission gear ratio of the continuously variable transmission 40 is set to the next gear position after the closest gear speed with reference to the gear ratio before switching instead of the closest gear speed.

  According to this configuration, when the shift mode is switched from the continuously variable automatic shift mode to the stepped automatic shift mode (hereinafter simply referred to as “switching” in this section), the speed that is closest to the rotational speed of the internal combustion engine is obtained. When the deviation from the set target rotational speed is less than the first predetermined value, the speed ratio of the continuously variable transmission is changed to the closest speed ratio, and the speed ratio before switching is set as the reference. Set to the next gear after the closest gear. Thereby, at the time of switching, the gear ratio of the continuously variable transmission can be forcibly greatly changed in the direction of the shift intended by the driver, and as a result, the driver obtains it by a downshift operation or an upshift operation. It is possible to appropriately respond to functions such as engine braking by downshift and acceleration demand by kickdown. Further, as described above, by greatly changing the gear ratio of the continuously variable transmission, the driver can clearly experience the sense of stepped driving at the time of switching.

  According to a fourth aspect of the present invention, in the control device for a continuously variable transmission for a vehicle according to the first or second aspect, a rotational speed detecting means (crank angle sensor 11) for detecting the rotational speed of the internal combustion engine 2; Target rotational speed setting means (ECU3) for setting the target rotational speed in accordance with the driving state of the vehicle V for each predetermined shift speed, and the stepped automatic transmission mode execution means By controlling the rotational speed to be the target rotational speed, it has a transmission ratio control means (ECU3) for controlling the transmission ratio of the continuously variable transmission 40, and the transmission ratio control means is in a continuously variable automatic transmission mode. The deviation between the rotational speed of the internal combustion engine 2 and the target rotational speed set for the closest gear position is less than a second predetermined value (ΔNE−β) when the transmission mode is switched from step to step automatic transmission mode. Sometimes the rotational speed of the internal combustion engine 2 is After changing the predetermined rotational speed (shift rotational speed ΔNE) (steps 56 and 76), control is performed so as to gradually approach the target rotational speed.

  According to this configuration, at the time of switching, when the deviation between the rotational speed of the internal combustion engine and the target rotational speed set for the gear position closest to the pre-switching gear ratio is less than the second predetermined value, After the engine speed is changed by a predetermined speed, the engine speed is controlled so as to gradually approach the target speed. As a result, even when the difference between the pre-switching gear ratio and the gear ratio set for the closest gear is small, the gear ratio of the continuously variable transmission can be greatly changed as required by the driver. Thus, the same effect as that of the third aspect can be obtained. Further, since the rotational speed of the internal combustion engine is once changed and then gradually approximated to the target rotational speed, the speed ratio of the continuously variable transmission can be smoothly returned to the speed ratio according to the operating state of the internal combustion engine. Further, when the deviation is equal to or greater than the second predetermined value, the engine speed is set to the target engine speed set for the gear closest to the pre-switching gear ratio without changing the engine speed. Control.

  According to a fifth aspect of the present invention, in the control device for a continuously variable transmission for a vehicle according to the first or second aspect, a rotational speed detection means (crank angle sensor 11) for detecting the rotational speed of the internal combustion engine 2, Target rotational speed setting means (ECU3) for setting the target rotational speed in accordance with the driving state of the vehicle V for each predetermined shift speed, and the stepped automatic transmission mode execution means The transmission ratio control means (ECU3) for controlling the transmission ratio of the continuously variable transmission 40 by controlling the rotation speed to the target rotation speed is provided. When the automatic transmission mode is switched to the stepped automatic transmission mode, the rotational speed of the internal combustion engine 2 is changed by a predetermined rotational speed (shift rotational speed ΔNE) (steps 34 and 44), and then gradually reaches the target rotational speed. Control to approach It is characterized in.

  According to this configuration, when the speed change mode is switched from the stepless automatic speed change mode to the stepped automatic speed change mode, the engine speed is gradually changed to the target speed after the predetermined speed is changed. To control. In this case, unlike the above-described claim 4, the rotational speed of the internal combustion engine is unconditionally changed regardless of the difference between the pre-switching gear ratio and the gear ratio set for the closest gear speed. As a result, the gear ratio of the continuously variable transmission can be reliably changed greatly as required by the driver.

  According to a sixth aspect of the present invention, in the control device for a continuously variable transmission for a vehicle according to the fourth or fifth aspect, the predetermined rotational speed (shift rotational speed ΔNE) is changed from the continuously variable automatic transmission mode to the stepped automatic transmission mode. It is characterized in that it is set according to the rotational speed of the internal combustion engine 2 at the time of switching the shift mode to or the closest shift stage.

  According to this configuration, the predetermined rotational speed to be changed at the time of switching is set according to the rotational speed of the internal combustion engine at the time of switching or the gear position closest to the pre-switching gear ratio, so that the shift shock at the time of switching is suppressed. However, it is possible to appropriately respond to the above-described functions required by the driver performing an upshift operation or a downshift operation.

  According to a seventh aspect of the present invention, in the control device for a continuously variable transmission for a vehicle according to any one of the first to sixth aspects, the switching operation means includes a changeover switch (MT switch 21) operated to switch the shift mode. And the shift mode setting means sets the shift mode to the continuously variable automatic shift mode when the changeover switch is operated in a state where the shift mode is set to the stepped automatic shift mode. To do.

  According to this configuration, the gear change mode of the continuously variable transmission can be changed from the stepped automatic transmission mode to the continuously variable automatic transmission mode only once by operating the changeover switch during the stepped automatic transmission mode. Easy switching by operation.

  According to an eighth aspect of the present invention, in the control device for a continuously variable transmission for a vehicle according to the first to sixth aspects, the switching operation means includes a shift lever operated to switch the shift range, The shift mode setting means sets the shift mode to the continuously variable automatic shift mode when the shift lever is operated in a state where the shift mode is set to the stepped automatic shift mode.

  According to this configuration, the gear change mode of the continuously variable transmission can be changed from the stepped automatic transmission mode to the continuously variable automatic transmission mode only once by operating the shift lever during the stepped automatic transmission mode. Easy switching by operation.

It is a figure which shows schematic structure of the vehicle drive system controlled by the control apparatus of the continuously variable transmission for vehicles by one Embodiment of this invention. It is a block diagram which shows roughly the control apparatus of the continuously variable transmission for vehicles. It is a figure which shows the shift range and shift position of a shift lever. It is a figure which shows the handle | steering-wheel which has MT switch and a gear stage change switch. It is a figure which shows the instrument panel which has a gear stage indicator and MT indicator. It is a flowchart which shows a transmission mode setting process. It is a flowchart which shows each transmission mode process. It is a flowchart which shows the AT mode upshift process by 1st Embodiment. It is a flowchart which shows the AT mode downshift process by 1st Embodiment. It is a flowchart which shows the AT mode upshift process by 2nd Embodiment. It is a flowchart which shows the AT mode downshift process by 2nd Embodiment. It is a figure which shows an example of a NOBJ table. It is a figure which shows an example of a gear stage table. It is a figure which shows an example of the NOBJ table for CVT modes.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. 1 and 2 show a schematic configuration of a vehicle drive system including a control device for a continuously variable transmission for a vehicle according to the present invention and an internal combustion engine. The control device 1 controls a gear ratio of a continuously variable transmission 40 described later.

  An internal combustion engine (hereinafter referred to as “engine”) 2 is a gasoline engine and is mounted on a vehicle V. The engine 2 is connected to drive wheels 7 and 7 via a flywheel 4, an automatic transmission 5, a differential gear mechanism 6, and the like, and the torque of the engine 2 is driven via these elements 4 to 6. It is transmitted to the wheels 7 and 7.

  The flywheel 4 is connected to the crankshaft 2a of the engine 2, and transmits the torque of the engine 2 to the automatic transmission 5 in a state where the fluctuation is reduced and the torsional vibration is attenuated.

  The automatic transmission 5 includes a forward / reverse switching mechanism 30, a continuously variable transmission 40, a starting clutch 50, and the like. The forward / reverse switching mechanism 30 includes an input shaft 31 and a planetary gear device 32 attached to the input shaft 31. The input shaft 31 is connected to the flywheel 4 at one end and penetrates through the hollow main shaft 41 in a rotatable manner. The planetary gear device 32 includes a sun gear 32a, a carrier 32d that rotatably supports a plurality of (for example, four) pinion gears 32b that mesh with the sun gear 32a, a ring gear 32c that meshes with each pinion gear 32b, and the like.

  The sun gear 32a is provided integrally with the input shaft 31, and a portion of the input shaft 31 closer to the engine 2 than the sun gear 32a is connected to the clutch inner 33a of the forward clutch 33. The clutch outer 33b includes a ring gear 32c and It is connected to the main shaft 41. Connection and disconnection of the forward clutch 33 are controlled by an ECU 3 described later. A reverse brake 34 is connected to the carrier 32d. The operation of the reverse brake 34 is also controlled by the ECU 3.

  With the above configuration, in the forward / reverse switching mechanism 30, when the vehicle V moves forward, the reverse brake 34 is released and the forward clutch 33 is connected, whereby the input shaft 31 and the main shaft 41 are directly connected, and the input shaft 31 The rotation is transmitted to the main shaft 41 as it is, and each pinion gear 32b does not rotate around its rotation axis, and the carrier 32d rotates integrally with the input shaft 31 in the same direction. As described above, when the vehicle moves forward, the main shaft 41 rotates in the same direction as the input shaft 31 at the same rotational speed. On the other hand, when the vehicle V travels backward, contrary to the above, the forward clutch 33 is disconnected and the reverse brake 34 is engaged, whereby the carrier 32d is locked. As a result, the rotation of the input shaft 31 is transmitted to the ring gear 32c via the sun gear 32a and the pinion gear 32b, whereby the ring gear 32c and the main shaft 41 connected thereto rotate in the opposite direction to the input shaft 31. Thus, the main shaft 41 rotates in the direction opposite to the input shaft 31 when the vehicle is moving backward.

  The continuously variable transmission 40 is of a belt type and includes the main shaft 41, the drive pulley 42, the counter shaft 43, the driven pulley 44, and the like.

  The drive pulley 42 includes a frustoconical movable portion 42a and a fixed portion 42b. The movable portion 42a is attached to the main shaft 41 so as to be movable in the axial direction and non-rotatable. The fixed portion 42b is fixed to the main shaft 41 and faces the movable portion 42a. Further, the mutually facing surfaces of the movable portion 42a and the fixed portion 42b are inclined so as to approach each other toward the central main shaft 41, whereby the movable portion 42a, the fixed portion 42b, and the main shaft 41 A V-shaped belt groove 42c is formed.

  The driven pulley 44 is configured in the same manner as the drive pulley 42, and has a frustoconical movable portion 44a and a fixed portion 44b. The movable portion 44a is attached to the countershaft 43 so as to be movable in the axial direction and non-rotatable. The fixed portion 44b is fixed to the countershaft 43 and faces the movable portion 44a. Further, the mutually facing surfaces of the movable portion 44a and the fixed portion 44b are inclined in the same manner as the movable portion 42a and the fixed portion 42b of the drive pulley 42, respectively, and the movable portion 44a, the fixed portion 44b, and the counter shaft 43 A V-shaped belt groove 44c is formed.

  A metal belt 45 is wound between the belt grooves 42c and 44c of the pulleys 42 and 44. The movable portions 42a and 44a are provided with pulley width variable mechanisms 46 and 46 for moving them in the axial direction, respectively. Each pulley width variable mechanism 46 includes an oil chamber 46a provided on the back side of the movable portions 42a and 44a, a hydraulic control valve 46b for controlling the hydraulic pressure supplied to the oil chamber 46a, and the like. The opening degree of 46b is controlled by ECU3.

  With the above configuration, in the continuously variable transmission 40, the hydraulic pressure control valve 46b is controlled by the ECU 3, whereby the hydraulic pressure in the oil chamber 46a is controlled, and the movable parts of the pulleys 42 and 44 are located at positions corresponding to the hydraulic pressure. 42a and 44a are positioned. As a result, the distance between the movable parts 42a, 44a and the fixed parts 42b, 44b, that is, the widths of the belt grooves 42c, 44c are set separately and continuously, so that the distance between the main shaft 41 and the counter shaft 43 is reduced. Can be changed steplessly, whereby the gear ratio of the continuously variable transmission 40 is controlled steplessly.

As will be described later, the speed change mode of the continuously variable transmission 40 is set to one of the following three speed change modes by the control device 1.
1. A continuously variable automatic transmission mode (hereinafter referred to as “CVT mode”) in which the gear ratio is set to be infinite according to the driving state of the vehicle V
2. A stepped automatic transmission mode (hereinafter referred to as “AT mode”) in which the transmission ratio is set to one of a plurality of predetermined transmission ratios according to the driving state of the vehicle V.
3. A stepped manual transmission mode (hereinafter referred to as “MT mode”) in which the transmission ratio is set to one of a plurality of predetermined transmission ratios in accordance with the driver's intention to change the transmission.

  The starting clutch 50 connects and disconnects the gear 43a rotatably provided on the counter shaft 43 and the counter shaft 43, and its operation is controlled by the ECU 3. The gear 43a meshes with the gear 6a of the differential gear mechanism 6 via large and small idler gears 51a and 51b provided on the idler shaft 51. With the above configuration, when the starting clutch 50 is connected, the rotation of the counter shaft 43 is transmitted to the drive wheels 7 and 7 through the gears 43a, 51a, 51b and 6a, and the drive wheels 7 and 7 are connected. When the vehicle starts to rotate, the vehicle V starts.

  FIG. 3 shows the shift range and shift position of the shift lever operated by the driver who drives the vehicle V. As the shift range of the shift lever, parking (P), reverse (R), neutral (N), drive (D), sport (S), low (L) ranges are set, and the shift position is in that order. Are lined up. In the sports range, in order to enable the engine 2 to be used at a higher speed, the gear ratio of the continuously variable transmission 40 is set to a higher side.

  Further, the shift lever is provided with a shift position sensor 20 for detecting the shift position. The ECU 3 responds to the detection signal to the forward clutch 33, the reverse brake 34, the pulley width variable mechanism 46 and the start. The operation of the clutch 50 is controlled. Further, when the shift lever is operated in a state where the transmission mode of the continuously variable transmission 40 is set to the AT mode or the MT mode, the transmission mode is switched to the CVT mode.

  As shown in FIG. 4, the handle H is provided with an MT switch 21 (switching switch) and shift speed change switches 22 and 22 (switching operation means). The MT switch 21 is disposed below the right switch 22 on the right and left sides, respectively. The MT switch 21 is operated by the driver in order to start or end the MT mode as the speed change mode of the continuously variable transmission 40. The MT switch 21 outputs the operation signal to the ECU 3, and the ECU 3 sets the speed change mode of the continuously variable transmission 40 according to the operation signal as described later.

  Each gear change switch 22 is operated by the driver to change the gear of the continuously variable transmission 40 during the MT mode, and includes an up switch 22a and a down switch 22b. The speed change switch 22 is connected to the ECU 3, and the ECU 3 increases the speed by one stage from the current speed every time the up switch 22a is operated during the MT mode, and operates the down switch 22b. Every time it is done, the gear position is lowered by one.

  Further, as shown in FIG. 5, a gear stage indicator 23 and an MT indicator 24 are provided on the instrument panel of the driver's seat together with a speedometer and the like. These indicators 23 and 24 are connected to the ECU 3. Under the control of the indicators 23 and 24, the former 23 lights up and displays the gear position in the AT mode or the MT mode, and the latter 24 lights up in the MT mode.

  In addition, a CRK signal is output to the ECU 3 from the crank angle sensor 11 (rotational speed detection means). This CRK signal is a pulse signal output at every predetermined crank angle as the crankshaft 2a of the engine 2 rotates. The ECU 3 obtains the engine speed NE based on the CRK signal. Further, a detection signal representing the vehicle speed VP, which is the speed of the vehicle V, is operated by the driver from the accelerator opening sensor 13 (driving state detecting means) from the vehicle speed sensor 12 (driving state detecting means). Detection signals indicating the accelerator opening AP, which is the opening of an accelerator pedal (not shown), are output.

  In this embodiment, the ECU 3 constitutes a continuously variable automatic transmission mode execution means, a stepped automatic transmission mode execution means, a transmission mode setting means, a target rotational speed setting means, and a transmission ratio control means, and an I / O interface. And a microcomputer composed of a CPU, a RAM, a ROM, and the like. The detection signals from the sensors 11 to 13 and the shift position sensor 20 are each A / D converted by the I / O interface and then input to the CPU. In accordance with these detection signals, the CPU sets the transmission mode of the continuously variable transmission 40 to any one of the CVT mode, the AT mode, and the MT mode according to a control program stored in the ROM. The transmission ratio of the continuously variable transmission 40 is controlled according to the changed transmission mode.

  FIG. 6 is a flowchart showing a shift mode setting process for setting the shift mode of the continuously variable transmission 40. This process is executed when the shift range is set to the drive range or the sports range. First, in step 1 (illustrated as “S1”, the same applies hereinafter), it is determined whether or not a failure of the continuously variable transmission 40 has already been detected.

  If the answer is YES and a failure of the continuously variable transmission 40 is detected, the AT mode execution flag F_AT and the MT mode execution flag F_MT are set to “0” (steps 2 and 3), and this program is terminated. . On the other hand, when the answer to step 1 is NO, it is determined whether or not the MT mode execution flag F_MT and the AT mode execution flag F_AT are “1” (steps 4 and 5).

  When both of these answers are NO and F_MT = 0 and F_AT = 0, that is, when the shift mode is set to the CVT mode, whether or not the up switch 22a of the shift speed change switch 22 has been operated (step 6). ) And whether or not the down switch 22b has been operated (step 7). If both of these answers are NO and the gear change switch 22 is not operated during the CVT mode, the AT mode upshift execution flag F_ATUP and the AT mode downshift execution flag F_ATDN are set to “0”, respectively (step) 8, 9).

  Next, at step 10, it is determined whether or not the MT switch 21 has been operated. If the answer is NO and the MT switch 21 is not operated during the CVT mode, the program is terminated as it is, and the CVT mode is maintained.

  If the answer to step 10 is YES and the MT switch 21 is operated during the CVT mode, the AT mode execution flag F_AT is set to “1” (step 11), and this program ends.

  If the answer to step 6 is YES and the up switch 22a is operated during the CVT mode, the AT mode upshift execution flag F_ATUP is set to “1” (step 12), and the AT mode downshift execution flag F_ATDN is set. After setting to “0” (step 13), the process further proceeds to step 11 to set the AT mode execution flag F_AT to “1”. If the answer to step 7 is YES and the down switch 22b is operated during the CVT mode, the AT mode upshift execution flag F_ATUP is set to “0” (step 14) and the AT mode downshift execution flag is set. After F_ATDN is set to “1” (step 15), the process proceeds to step 11 and the AT mode execution flag F_AT is set to “1” in the same manner as when the up switch 22a is operated.

  As described above, when the up switch 22a or the down switch 22b of the gear position change switch 22 is operated during the CVT mode, the AT mode execution flag F_AT is set in step 11 in the same manner as when the MT switch 21 is operated. Is set to “1”, whereby the transmission mode is set to the AT mode. By executing step 11, the answer to step 5 becomes YES. In this case, it is determined whether or not the MT switch 21 has been operated (step 16).

  If the answer is YES and the MT switch 21 is operated during the AT mode, the AT mode execution flag F_AT is set to “0” (step 17), and the shift mode is set to the CVT mode. With this setting, when the MT switch 21 or the gear change switch 22 is erroneously operated during the CVT mode and the mode is shifted to the AT mode, by operating the MT switch 21, Can be immediately returned to the CVT mode.

  If the answer to step 16 is NO and the MT switch 21 is not operated during the AT mode, it is determined whether or not the up switch 22a or the down switch 22b of the gear position change switch 22 has been operated (step 18). . If the answer is no and there is no such operation, the program is terminated as it is and the AT mode is maintained.

  If the answer to step 18 is YES, and the upshift operation or downshift operation of the gear change switch 22 is performed during the AT mode, the operation of the MT switch 21, the up switch 22a, or the down switch 22b during the CVT mode is incorrect. Instead, assuming that the driver desires the MT mode, the AT mode execution flag F_AT is set to “0” (step 19) and the MT mode execution flag F_MT is set to “1” (step 20). The transmission mode is switched from the AT mode to the MT mode. By executing step 20, the answer to step 4 is YES. In this case, it is determined whether or not the MT switch 21 has been operated (step 21). If the answer is no, the program is terminated as it is and the MT mode is maintained.

  If the answer to step 21 is YES and the MT switch 21 is operated during the MT mode, the MT mode execution flag F_MT is set to “0” (step 22) to switch the shift mode from the MT mode to the CVT mode. End this program.

  FIG. 7 is a flowchart showing an execution process in each shift mode. In this process, the target rotational speed NOBJ corresponding to the shift speed or speed ratio of the set shift mode is set according to the shift mode set as described above and the driving state of the vehicle V.

  First, in step 21, it is determined whether or not the MT mode execution flag F_MT is “1”. If the answer is YES and the speed change mode is set to MT mode, MT mode processing is executed (step 22).

  In this MT mode process, first, the gear to be set is set according to the operation state of the gear change switch 22. Specifically, when the shift mode is switched from the AT mode to the MT mode, a shift stage that is one stage up or down from the shift stage in the AT mode immediately before the switching is set. Then, the target rotational speed NOBJ corresponding to the gear position is set. The target rotational speed NOBJ is set according to the vehicle speed VP, for example, based on the NOBJ table shown in FIG. This NOBJ table represents the relationship between the vehicle speed VP and the target rotational speed NOBJ, and its inclination corresponds to the gear ratio to be set at each gear stage. Therefore, the higher the gear position, the smaller the slope corresponding to the gear ratio. As a result, by controlling the continuously variable transmission 40 so that the engine rotational speed NE becomes equal to the target rotational speed NOBJ, the speed ratio of the continuously variable transmission 40 becomes the speed ratio that the set speed stage should have. Is set.

  As described above, in the MT mode, the shift speed is set according to the vehicle speed VP and the shift speed of the AT mode immediately before switching, and thereafter, every time the driver operates the shift speed change switch 22, the shift speed is set to 1. Step up or down step by step.

  Returning to FIG. 7, when the answer to step 21 is NO and the shift mode is not set to the MT mode, it is determined whether or not the AT mode execution flag F_AT is “1” (step 23). When the answer is NO and the shift mode is set to the CVT mode, the CVT mode process is executed (step 24).

  In this CVT mode process, the target rotational speed NOBJ is set according to the vehicle speed VP and the accelerator pedal opening AP. This target rotational speed NOBJ is set based on, for example, the NOBJ table for CVT mode shown in FIG. This NOBJ table is composed of a plurality of tables set for each predetermined accelerator opening AP in the range of 0% to 100%, and when the accelerator opening AP shows an intermediate value thereof, The rotational speed NOBJ is obtained by interpolation calculation. In these tables, the target rotational speed NOBJ is set to a larger value as the vehicle speed VP is larger and the accelerator pedal opening AP is larger.

  As described above, in the CVT mode, the target rotation speed NOBJ is set steplessly according to the vehicle speed VP and the accelerator pedal opening AP, so that the gear ratio of the continuously variable transmission 40 is set steplessly.

  Returning to FIG. 7, if the answer to step 23 is YES and the shift mode is set to the AT mode, whether or not the AT mode upshift execution flag F_ATUP and the AT mode downshift execution flag F_ATDN are “1”. Are respectively determined (steps 25 and 26). When both of these answers are NO, that is, when switching to the AT mode is not performed by the operation of the gear change switch 22 but by the operation of the MT switch 21, the process proceeds to step 27 to execute the AT mode normal process. To do. In this AT mode normal processing, the gear position of the continuously variable transmission 40 is selected according to the vehicle speed VP and the accelerator pedal opening AP based on the gear position table shown in FIG.

  This gear table is set separately for upshift (solid line) and downshift (dotted line), and the regions of the first to seventh gears are divided by boundary lines L12 to L67 and L21 to L76. Are set so as to have a large hysteresis. Specifically, the setting / change of the gear position is performed as follows. Immediately after switching from the CVT mode to the AT mode, the gear position corresponding to the upshift region including the vehicle speed VP and the accelerator pedal opening AP is set. Further, for example, when the shift speed is set to the first speed, the boundary line L12 between the first speed and the second speed for the upshift is obtained when the accelerator pedal opening AP is constant and the vehicle speed VP is increased. Is exceeded, the shift speed is changed from the first speed to the second speed. Further, when the shift speed is set to the second speed, when the vehicle speed VP exceeds the downshift boundary L21 due to the decrease in the vehicle speed VP, the shift speed is changed from the second speed to the first speed. Changed to

  Next, the target rotational speed NOBJ in the AT mode is set. The target rotational speed NOBJ is set by searching the NOBJ table shown in FIG. 12 in the same manner as the target rotational speed NOBJ in the MT mode, according to the gear stage set in the gear stage table. . As described above, in the AT mode, the gear stage is set according to the vehicle speed VP and the accelerator pedal opening AP, and the gear ratio of the continuously variable transmission 40 is set stepwise to the gear ratio according to the selected gear stage. Is done.

  Returning to FIG. 7, when the answer to step 25 is YES and the AT mode upshift execution flag F_ATUP is “1”, that is, when the mode is switched to the AT mode by operating the up switch 22a in the CVT mode, the AT mode An upshift process is executed (step 28).

  As shown in FIG. 8, in this AT mode upshift process, first, in step 31, it is determined whether or not the previous value of the AT mode upshift execution flag F_ATUP is “0”. When this answer is YES, that is, when this time is immediately after switching from the CVT mode to the AT mode, the continuously variable transmission 40 according to the vehicle speed VP and the engine speed NE based on the shift speed table of FIG. Is set to the closest gear position on the high speed side with respect to the gear ratio in the CVT mode immediately before switching (hereinafter referred to as “the gear ratio before switching”) (step 32).

  Next, the routine proceeds to step 33, and based on a ΔNE table (not shown), a shift rotational speed ΔNE (predetermined rotational speed), which will be described later, according to the vehicle speed VP and the engine rotational speed NE, or according to the vehicle speed VP and the shift stage set in step 32 above. Number). In the ΔNE table, the shift rotational speed ΔNE is set to a larger value as the vehicle speed VP is larger, the engine rotational speed NE is larger, and the set shift speed is larger.

  Next, the routine proceeds to step 34, where the value obtained by subtracting the shift rotational speed ΔNE set at step 33 from the engine rotational speed NE is set as the target rotational speed NECMD, and this program is terminated. The target rotational speed NECMD is actually used as the target rotational speed for controlling the engine rotational speed NE in the AT mode upshift process and the AT mode downshift process.

  When the answer to step 31 is NO, that is, when this time is the second and subsequent loops that have shifted to the AT mode, the routine proceeds to step 35, where the speed of FIG. Based on the NOBJ table, NOBJ which is the final target rotational speed is set. In the following description, this NOBJ is referred to as “final target rotational speed”.

  Next, it is determined whether or not the absolute value of the deviation between the target rotational speed NECMD and the final target rotational speed NOBJ set in step 35 is larger than a predetermined value α (for example, 10 rpm) (step 36). If the answer is YES and | NECMD−NOBJ |> α, the routine proceeds to step 37, where it is determined whether or not the target rotational speed NECMD is larger than the final target rotational speed NOBJ. If the answer is YES and NECMD> NOBJ, a value obtained by subtracting the predetermined value α from the target rotational speed NECMD is set as the current target rotational speed NECMD (step 38), and the program is terminated. On the other hand, if the answer to step 37 is NO and NECMD ≦ NOBJ, a value obtained by adding a predetermined value α to the target rotational speed NECMD is set as the current target rotational speed NECMD (step 39), and the program is terminated.

  On the other hand, when the answer to step 36 is NO, that is, when | NCMD-NOBJ | ≦ α and the target rotational speed NECMD is substantially equal to the final target rotational speed NOBJ, the target rotational speed NECMD is set to the final target rotational speed NOBJ. (Step 40), the program is terminated.

  As described above, when the speed change mode is switched from the CVT mode to the AT mode by the operation of the up switch 22a, immediately after that, the target rotational speed NECMD is equal to the shift rotational speed ΔNE from the engine rotational speed NE at that time. Set to the reduced value. Thereafter, the target rotational speed is determined according to the magnitude relationship between the absolute value of the deviation between the target rotational speed NECMD and the final target rotational speed NOBJ and the predetermined value α, and the magnitude relation between the target rotational speed NECMD and the final target rotational speed NOBJ. By adding or subtracting a predetermined value α to or from the number NECMD, the target rotational speed NECMD that has been decreased immediately after switching is controlled so as to gradually approach the final target rotational speed NOBJ and converge to the final target rotational speed NOBJ. .

  Returning to FIG. 7, when the answer to step 26 is YES, that is, when the mode is switched to the AT mode by operating the down switch 22b in the CVT mode, an AT mode downshift process is executed (step 29).

  As shown in FIG. 9, in this AT mode downshift process, first, in step 41, it is determined whether or not the previous value of the AT mode downshift execution flag F_ATDN is “0”. When this answer is YES, that is, when this time is immediately after switching from the CVT mode to the AT mode, the continuously variable transmission 40 according to the vehicle speed VP and the engine speed NE based on the shift speed table of FIG. Is set to the closest speed on the low speed side with respect to the pre-switching speed ratio (step 42).

  Next, the routine proceeds to step 43, in the same manner as in the AT mode upshift process described above, based on the ΔNE table, according to the vehicle speed VP and the engine speed NE, or according to the vehicle speed VP and the gear position set at step 42, A shift rotational speed ΔNE to be changed immediately after the operation of the down switch 22b is set. In the following step 44, a value obtained by adding the shift rotational speed ΔNE to the engine rotational speed NE is set as the target rotational speed NECMD, and this program is terminated.

  When the answer to step 41 is NO, that is, when this time is the second and subsequent loops that have shifted to the AT mode, the routine proceeds to step 45, where NOBJ in FIG. 12 is selected according to the vehicle speed VP and the gear set in step 42. Based on the table, the final target rotational speed NOBJ is set.

  Next, it is determined whether or not the absolute value of the deviation between the final target rotational speed NOBJ and the target rotational speed NECMD set in steps 45 and 44 is larger than a predetermined value α (step 46). If the answer is YES and | NOBJ−NECMD |> α, the routine proceeds to step 47, where it is determined whether or not the final target rotational speed NOBJ is larger than the target rotational speed NECMD. If the answer is YES and NOBJ> NECMD, a value obtained by adding a predetermined value α to the target rotational speed NECMD is set as the current target rotational speed NECMD (step 48), and this program is terminated. On the other hand, if the answer to step 47 is NO and NOBJ ≦ NECMD, a value obtained by subtracting the predetermined value α from the target rotational speed NECMD is set as the current target rotational speed NECMD (step 49), and the program ends.

  On the other hand, when the answer to step 46 is NO, that is, when | NOBJ−NECMD | ≦ α and the target rotational speed NECMD is substantially equal to the final target rotational speed NOBJ, the target rotational speed NECMD is set to the final target rotational speed NOBJ. (Step 50), the program is terminated.

  As described above, when the shift mode is switched from the CVT mode to the AT mode by operating the down switch 22b, immediately after that, the target rotational speed NECMD is equal to the shift rotational speed ΔNE from the engine rotational speed NE at that time. Set to increased value. Thereafter, the target rotational speed is determined according to the magnitude relationship between the absolute value of the deviation between the final target rotational speed NOBJ and the target rotational speed NECMD and the predetermined value α, and the magnitude relation between the final target rotational speed NOBJ and the target rotational speed NECMD. By adding / subtracting the predetermined value α to / from the number NECMD, the target rotational speed NECMD increased immediately after switching is controlled so as to gradually approach the final target rotational speed NOBJ and converge to the final target rotational speed NOBJ. .

  As described above in detail, according to the present embodiment, when the driver operates the MT switch 21 or the gear change switch 22 during the CVT mode, the gear change mode of the continuously variable transmission 40 is changed from the CVT mode. Switch to AT mode. In this way, the shift mode of the continuously variable transmission 40 can be easily and quickly switched to the AT mode simply by operating the up switch 22a or the down switch 22b during the CVT mode. When the up switch 22a or the down switch 22b is operated, the gear position of the continuously variable transmission 40 is on the same side as the speed change direction by the up switch 22a or the down switch 22b with respect to the gear ratio before switching. , The closest gear position is set. Therefore, the shift stage of the continuously variable transmission can be appropriately set in the direction of the shift intended by the driver when performing either a shift on the high speed side or the low speed side. Further, even when the gear change mode of the continuously variable transmission 40 is switched from the CVT mode to the AT mode due to a driver's erroneous operation or the like, in the AT mode, the gear ratio of the continuously variable transmission 40 becomes the driving state of the vehicle V. Since an appropriate gear position is set as needed, the engine torque can be ensured without excess and deficiency, and the occurrence of overrevs can be appropriately prevented.

  In addition, when the up switch 22a or the down switch 22b is operated during the CVT mode, the target rotational speed NECMD is forcibly increased or decreased by the shift rotational speed ΔNE in the same direction as the speed change by that, so that the driver can It is possible to appropriately respond to functions required by a shift operation or an upshift operation, for example, an engine brake by a downshift or a request for acceleration by a kickdown. Further, as described above, when the mode is switched to the AT mode, the driver can clearly feel the stepped driving feeling by greatly increasing or decreasing the target rotational speed NECMD.

  Further, since the shift rotational speed ΔNE is set according to the engine rotational speed NE or the set shift speed, the driver can perform an upshift operation or a downshift operation while suppressing a shift shock at the time of switching. It is possible to appropriately respond to the above-described functions that are required. Further, the AT mode can be easily switched to the CVT mode by one operation only by operating the MT switch 21 or the shift lever during the operation in the AT mode.

  Next, AT mode upshift processing and AT mode downshift processing according to the second embodiment of the present invention will be described with reference to FIGS. In the following description, the above-described embodiment will be referred to as the first embodiment, and the description will focus on the parts that are different from the first embodiment.

  As shown in FIG. 10, in the AT mode upshift process of the second embodiment, first, as in step 31 of the first embodiment, it is determined whether or not the previous value of F_ATUP is “0” (step 51). ). If the answer is YES and this time is immediately after switching from the CVT mode to the AT mode by the operation of the up switch 22a, the vehicle speed VP and the engine speed are based on the shift speed table of FIG. 12 as in the first embodiment. In response to NE, the gear position of continuously variable transmission 40 is set to the closest gear position on the high speed side with respect to the pre-switching gear ratio (step 52).

  Next, the final target rotation speed NOBJ is calculated according to the vehicle speed VP and the gear position set at step 52 (step 53), and according to the vehicle speed VP and the engine rotation speed NE, or the vehicle speed VP and the set gear speed. Accordingly, the shift rotational speed ΔNE is set (step 54). In the following step 55, it is determined whether or not the deviation between the engine rotational speed NE and the final target rotational speed NOBJ is smaller than the difference (second predetermined value) between the shift rotational speed ΔNE and a predetermined value β (for example, 10 rpm). Determine. If the answer is YES and NE-NOBJ <ΔNE-β, a value obtained by subtracting the shift rotational speed ΔNE from the engine rotational speed NE is set as the target rotational speed NECMD (step 56), and the program is terminated. On the other hand, when the answer to step 55 is NO and NE-NOBJ ≧ ΔNE-β, the routine proceeds to step 57, where the target rotational speed NECMD is set to the final target rotational speed NOBJ, and this program ends.

  If the answer to step 51 is NO and this time is the second and subsequent loops that have shifted to the AT mode, the final target rotational speed NOBJ is set in accordance with the vehicle speed VP and the speed set in step 52 (step 58).

  Next, at step 59, it is determined whether or not the absolute value of the deviation between the target rotational speed NECMD and the final target rotational speed NOBJ is greater than a predetermined value α. If the answer is YES and | NECMD−NOBJ |> α, the process proceeds to step 60 to determine whether or not the target rotational speed NECMD is greater than the final target rotational speed NOBJ. When the answer is YES, a value obtained by subtracting the predetermined value α from the target rotational speed NECMD is set as the current target rotational speed NECMD (step 61), and the program is terminated. On the other hand, if the answer to step 60 is NO and NECMD ≦ NOBJ, a value obtained by adding a predetermined value α to the target rotational speed NECMD is set as the current target rotational speed NECMD (step 62), and the program is terminated.

  When the answer to step 59 is NO and | NECMD-NOBJ | ≦ α, step 57 is executed and the program is terminated.

  Next, the AT mode downshift process of the second embodiment will be described with reference to FIG. As shown in the figure, in this AT mode downshift process, first, as in the first embodiment, it is determined whether or not the previous value of F_ATDN is “0” (step 71). If the answer is YES and this time is immediately after switching from the CVT mode to the AT mode by the operation of the down switch 22b, the vehicle speed VP and the engine speed are based on the shift speed table of FIG. 12 as in the first embodiment. In response to NE, the gear position of continuously variable transmission 40 is set to the closest gear position on the low speed side with respect to the pre-switching gear ratio (step 72).

  Next, the final target rotational speed NOBJ is calculated according to the vehicle speed VP and the gear position set at step 72 (step 73), and according to the vehicle speed VP and the engine speed NE, or the vehicle speed VP and the set gear speed. Accordingly, a shift rotational speed ΔNE is set (step 74). In the following step 75, it is determined whether or not the deviation between the final target rotational speed NOBJ and the engine rotational speed NE is smaller than the difference (second predetermined value) between the shift rotational speed ΔNE and the predetermined value β. If the answer is YES and NOBJ−NE <ΔNE−β, a value obtained by adding the shift rotational speed ΔNE to the engine rotational speed NE is set as the current target rotational speed NECMD (step 76), and the program is terminated. . On the other hand, when the answer to step 75 is NO and NOBJ−NE ≧ ΔNE−β, the routine proceeds to step 77 where the target rotational speed NECMD is set to the final target rotational speed NOBJ and the program is terminated.

  If the answer to step 71 is NO and this time is the second and subsequent loops in which the mode has shifted to the AT mode, the final target rotational speed NOBJ is set according to the vehicle speed VP and the speed set in step 72 (step 78). ).

  Next, at step 79, it is determined whether or not the absolute value of the deviation between the final target rotational speed NOBJ and the target rotational speed NECMD is greater than a predetermined value α. If the answer is YES and | NOBJ−NECMD |> α, the routine proceeds to step 80, where it is determined whether or not the final target rotational speed NOBJ is larger than the target rotational speed NECMD. If the answer is YES and NOBJ> NECMD, a value obtained by adding a predetermined value α to the target rotational speed NECMD is set as the current target rotational speed NECMD (step 81), and this program is terminated. On the other hand, if the answer to step 80 is NO and NOBJ ≦ NECMD, a value obtained by subtracting the predetermined value α from the target rotational speed NECMD is set as the current target rotational speed NECMD (step 82), and the program is terminated.

  When the answer to step 79 is NO and | NOBJ-NECMD | ≦ α, the step 77 is executed and the program is terminated.

  As described in detail above, this second embodiment can achieve the same effects as those of the first embodiment described above. Further, in this embodiment, when switching from the CVT mode to the AT mode by operating the up switch 22a or the down switch 22b, the difference between the pre-switching gear ratio and the gear ratio set for the closest gear stage is as follows. Even when the speed is small, the gear ratio of the continuously variable transmission 40 is forcibly changed greatly, so that it is possible to appropriately and reliably respond to a function that the driver seeks through a downshift operation or an upshift operation.

  Further, in the above embodiment, when the up switch 22a or the down switch 22b is operated during the CVT mode, the gear position of the continuously variable transmission 40 is set to the up switch 22a or the down switch 22b with respect to the pre-switching gear ratio. However, the deviation between the engine rotational speed NE and the final target rotational speed NOBJ set at the closest gear is relatively small. If it is less than the value (first predetermined value), the speed stage of the continuously variable transmission 40 may be set to the next speed stage after the nearest speed stage with reference to the pre-switching speed ratio. In this way, by changing the shift speed of the continuously variable transmission 40 by one or more stages, it is possible to forcibly greatly change the shift direction required by the driver, and as a result, the driver can downshift. It is possible to appropriately and reliably respond to the above-described functions required by operation or upshift operation.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Control apparatus 2 Internal combustion engine 3 ECU (continuously variable transmission mode execution means, stepped automatic transmission mode execution means,
(Speed change mode setting means, target speed setting means, speed ratio control means)
11 Crank angle sensor (rotation speed detection means)
12 Vehicle speed sensor (driving condition detection means)
13 Accelerator opening sensor (operating state detection means)
21 MT switch (changeover switch)
22 Speed change switch (switching operation means)
22a up switch 22b down switch 40 continuously variable transmission V vehicle VP vehicle speed AP accelerator opening NE engine speed NOBJ target speed ΔNe shift speed (predetermined speed)
NECMD target speed

Claims (8)

A control device for a continuously variable transmission for a vehicle capable of steplessly shifting the output of an internal combustion engine mounted on the vehicle,
Driving state detecting means for detecting the driving state of the vehicle;
Continuously variable automatic transmission mode execution means for executing a continuously variable automatic transmission mode for setting the transmission ratio of the continuously variable transmission continuously according to the detected driving state of the vehicle;
A stepped automatic transmission mode executing means for executing a stepped automatic transmission mode for setting the transmission ratio of the continuously variable transmission to one of a plurality of predetermined gears according to the detected driving state of the vehicle;
Switching operation means operated to switch the transmission mode of the continuously variable transmission;
Shift mode setting means for setting the shift mode of the continuously variable transmission to one of the continuously variable automatic shift mode and the stepped automatic shift mode according to the operation state of the switching operation means;
The stepped automatic transmission mode execution means sets the transmission ratio of the continuously variable transmission of the plurality of predetermined gears when the transmission mode is switched from the continuously variable automatic transmission mode to the stepped automatic transmission mode. Of these, the control device for a continuously variable transmission for a vehicle is set to one closest to the pre-switching speed ratio set in the continuously variable automatic transmission mode immediately before the switching. The switching operation means has an up switch for raising and a down switch for lowering the gear stage of the continuously variable transmission,
The stepped automatic transmission mode execution means sets the transmission ratio of the continuously variable transmission to a higher speed than the speed ratio before switching when the up switch is operated in the continuously variable automatic transmission mode. 2. The vehicle according to claim 1, wherein, when the down switch is operated, the speed ratio of the continuously variable transmission is set to a speed lower than the speed ratio before switching. Control device for continuously variable transmission. A rotational speed detection means for detecting the rotational speed of the internal combustion engine;
A target rotation speed setting means for setting a target rotation speed for each of the plurality of predetermined shift speeds according to the driving state of the vehicle;
The stepped automatic shift mode execution means is set for the speed that is closest to the rotational speed of the internal combustion engine when the shift mode is switched from the continuously variable automatic shift mode to the stepped automatic shift mode. When the deviation from the target rotational speed is less than a first predetermined value, the gear ratio of the continuously variable transmission is changed to the nearest gear position based on the gear ratio before switching instead of the nearest gear speed. 2. The control device for a continuously variable transmission for a vehicle according to claim 1, wherein A rotational speed detection means for detecting the rotational speed of the internal combustion engine;
A target rotation speed setting means for setting a target rotation speed for each of the plurality of predetermined shift speeds according to the driving state of the vehicle;
The stepped automatic transmission mode execution means includes a transmission ratio control means for controlling the transmission ratio of the continuously variable transmission by controlling the rotational speed of the internal combustion engine to be the target rotational speed. ,
The gear ratio control means is configured to change the speed of the internal combustion engine and the target speed set for the closest speed at the time of switching the speed change mode from the stepless automatic speed change mode to the stepped automatic speed change mode. The engine speed is controlled so as to gradually approach the target speed after changing the speed of the internal combustion engine by a predetermined speed when the deviation is less than a second predetermined value. Or a control device for a continuously variable transmission for a vehicle according to 2; A rotational speed detection means for detecting the rotational speed of the internal combustion engine;
A target rotation speed setting means for setting a target rotation speed for each of the plurality of predetermined shift speeds according to the driving state of the vehicle;
The stepped automatic transmission mode execution means includes a transmission ratio control means for controlling the transmission ratio of the continuously variable transmission by controlling the rotational speed of the internal combustion engine to be the target rotational speed. ,
The gear ratio control means changes the rotational speed of the internal combustion engine by a predetermined rotational speed when the shift mode is switched from the continuously variable automatic shift mode to the stepped automatic shift mode, and then performs the target rotation. 3. The control device for a continuously variable transmission for a vehicle according to claim 1, wherein the control is performed so as to gradually approach the number.   The predetermined rotation speed is set according to the rotation speed of the internal combustion engine at the time of switching the shift mode from the continuously variable automatic shift mode to the stepped automatic shift mode, or the closest shift speed. The control device for a continuously variable transmission for a vehicle according to claim 4 or 5. The changeover operation means has a changeover switch operated to change the shift mode.
The shift mode setting means sets the shift mode to the continuously variable automatic shift mode when the changeover switch is operated in a state where the shift mode is set to the stepped automatic shift mode. A control device for a continuously variable transmission for a vehicle according to any one of claims 1 to 6. The switching operation means has a shift lever operated to switch the shift range,
The shift mode setting means sets the shift mode to the continuously variable automatic shift mode when the shift lever is operated in a state where the shift mode is set to the stepped automatic shift mode. A control device for a continuously variable transmission for a vehicle according to any one of claims 1 to 6.

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