JP4987046B2 - Vehicle equipped with continuously variable transmission and control method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve fuel economy effect equivalent to a two wheel drive vehicle in a four wheel drive vehicle equipped with a continuously variable transmission performing neutral control. <P>SOLUTION: This invention includes a clutch meet point learning control means (S5) detecting the rotation of a primary pulley while changing a state of a forward clutch to an engagement state when the forward clutch is maintained in a disengagement state by neutral control and learning and controlling a clutch meeting point based on oil supply pressure at a point of time when the rotation is detected at the first time in the vehicle equipped with the continuously variable transmission capable of travelling in a four wheel drive state, and performs learning control after changing a drive state to a two wheel drive state when it is determined that restart in a four wheel drive state is not required in restart of the vehicle (S4). <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to control of a four-wheel drive vehicle equipped with a continuously variable transmission that performs neutral control.

  In a vehicle equipped with a continuously variable transmission, while the shift position is set to the D range, when the driver depresses the brake pedal and stops, the forward clutch is released to disengage the engine side and the transmission side, and the engine Neutral control that improves fuel efficiency by reducing the driving load is known. Since the clutch needs to be immediately engaged when the vehicle restarts, the clutch pressure at the neutral control is controlled to a predetermined clutch pressure slightly lower than the clutch pressure at which the clutch starts torque transmission.

  However, the clutch engagement point, which is the point at which the clutch starts torque transmission, may fluctuate due to variations in the hydraulic system, individual differences in the components that make up the clutch, etc., so learning control of the clutch engagement point should be performed during neutral control. Is described in Patent Document 1. In Patent Document 1, the clutch pressure is gradually increased during the neutral control, and the clutch engagement point is estimated based on the clutch pressure at the time when the pulse from the rotation speed sensor of the primary pulley is detected.

  That is, when the clutch pressure is gradually increased as described above, the clutch is dragged at the clutch engagement point and torque transmission is started, which causes a minute twist on the output side member of the clutch. The minute rotation of the primary pulley due to the twist is detected by a rotation speed sensor.

JP 2008-106814 A

  However, the four-wheel drive vehicle has more shaft parts for transmitting the drive force than the two-wheel drive vehicle that transmits the drive force only to the front wheels or the rear wheels. The inertia from the transmission on the side to the drive wheel is large, and the torsional rigidity is correspondingly increased. Since the torsional displacement amount of the shafts decreases due to the increase in the torsional rigidity on the output side, the rotational displacement amount of the primary pulley becomes small, and pulses of the rotational speed sensor of the primary pulley are hardly generated. Thereby, since the time required for the learning control becomes longer, the clutch is held in the drag state for a longer time, and the durability of the clutch may be reduced as compared with the two-wheel drive vehicle.

  An object of the present invention is to realize a fuel efficiency effect equivalent to that of a two-wheel drive vehicle in a four-wheel drive vehicle equipped with a continuously variable transmission that performs neutral control.

  The present invention relates to a continuously variable transmission that includes a primary pulley to which driving force of an engine is input, a secondary pulley that outputs driving force to driving wheels, and a winding member that is wound around the primary pulley and the secondary pulley. And a clutch capable of selectively transmitting the driving force from the engine to the primary pulley according to the supplied hydraulic pressure, a two-wheel drive state for driving the front wheels or the rear wheels, and a four-wheel drive for driving the front wheels and the rear wheels In a vehicle equipped with a continuously variable transmission capable of switching between states, a predetermined state in which the vehicle is stopped in a state in which a rotation detecting means for detecting the rotation of the primary pulley and a travel range in which the clutch is held in the engaged state are selected. When the vehicle enters the state, the neutral control means for controlling the clutch to the non-engaged state until the vehicle restarts, and the drive when the vehicle enters the predetermined state When the vehicle is in a four-wheel drive state, the four-wheel drive necessity determination means for determining whether or not it is necessary to start in the four-wheel drive state when the vehicle restarts, and in the four-wheel drive state when the vehicle restarts When it is determined that it is not necessary to start, the driving state switching means for switching the driving state to the two-wheel driving state, and the neutral state controlling means controls the non-engaged state after the driving state is switched to the two-wheel driving state. Detecting the rotation of the primary pulley by the rotation detecting means while changing the clutch to the engaged state, or detecting the rotation of the primary pulley by the rotation detecting means while controlling the clutch to the non-engaged state by the neutral control means, Based on the supply hydraulic pressure at the time when rotation is first detected, the supply hydraulic pressure when the clutch switches from the non-engaged state to the engaged state is learned. Characterized in that it comprises a clutch meet point learning control means for.

  The present invention also provides a continuously variable transmission including a primary pulley to which driving force of an engine is input, a secondary pulley that outputs driving force to driving wheels, and a winding member that is wound around the primary pulley and the secondary pulley. And a four-wheel drive state for driving the front wheel and the rear wheel, and a two-wheel drive state for driving the front wheel or the rear wheel, and a clutch capable of selectively transmitting the driving force from the engine to the primary pulley according to the supplied hydraulic pressure A method for controlling a vehicle equipped with a continuously variable transmission capable of switching between a driving state, wherein the vehicle stops in a state where a step of detecting the rotation of a primary pulley and a travel range in which a clutch is held in an engaged state are selected. When the vehicle is in a predetermined state, the step of controlling the clutch to a neutral state in which the clutch is not engaged until the vehicle restarts, and the vehicle is in a predetermined state When the vehicle is in a four-wheel drive state, the vehicle determines whether or not it is necessary to start in the four-wheel drive state when the vehicle restarts, and in the four-wheel drive state when the vehicle restarts. A clutch that is controlled to a non-engaged state by a step of switching the drive state to the two-wheel drive state when it is determined that it is not necessary to start, and a step of controlling after the drive state is switched to the two-wheel drive state The rotation of the primary pulley is detected by the step of detecting while changing the clutch to the engaged state, or the rotation of the primary pulley is detected by the step of detecting while controlling the clutch to the non-engaged state by the step of controlling. Based on the supply hydraulic pressure at the time when the clutch is detected, the supply hydraulic pressure when the clutch switches from the non-engaged state to the engaged state is learned. It characterized in that it comprises the steps of:.

  According to the present invention, in a vehicle that can travel in a four-wheel drive state, when the drive state at the start of neutral control is the four-wheel drive state, is it necessary to restart in the four-wheel drive state when the vehicle restarts? When it is determined that it is not necessary, the clutch meet point learning control is performed after switching the driving state to the two-wheel driving state, so that the inertia on the output side of the clutch during the learning control can be further reduced. The rotation of the primary pulley can be detected earlier by reducing the inertia. As a result, the time for holding the clutch in the dragged state can be shortened as compared with the case where learning control is performed in the four-wheel drive state, so that appropriate learning control can be performed without being affected by the increase in inertia, A decrease in the durability of the clutch can be prevented.

It is a block diagram which shows the structure of the continuously variable transmission mounting vehicle in this embodiment. It is a block diagram which shows the structure from an engine to a continuously variable transmission. It is a flowchart which shows control of the continuously variable transmission mounting vehicle in this embodiment. It is a time chart which shows clutch meet point learning control. It is a time chart which shows the effect | action of the continuously variable transmission mounting vehicle in this embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a schematic configuration diagram showing a configuration of a continuously variable transmission-equipped vehicle in the present embodiment. The continuously variable transmission vehicle includes an engine 1, a continuously variable transmission 5 coupled to the output shaft of the engine 1, a transfer 61 coupled to the output shaft of the continuously variable transmission 5, and the transfer 61 to the propeller shaft 62. The control unit 20 includes an electronic control coupling 63 that selectively transmits torque transmitted through the rear differential gear 64 to the rear differential gear 64.

  The driving force of the engine 1 is input to the continuously variable transmission 5, shifted at a predetermined gear ratio, transmitted to the front wheels 65 via the front differential gear, and transferred from the continuously variable transmission 5 to the transfer 61 and the propeller shaft 62. To the electronic control coupling 63, and to the rear wheel 66 via the rear differential gear 64.

  The electronic control coupling 63 has a clutch whose engagement state can be controlled by a solenoid, and selectively transmits torque input from the propeller shaft 62 to the rear differential gear 64 by changing the engagement state of the clutch. The engagement force of the clutch changes according to the solenoid current, and is set so that the engagement force increases as the solenoid current increases. The relationship between the solenoid current and the clutch engagement force is not limited to this, and it may be set so that the engagement force increases as the solenoid current decreases.

  The control unit 20 includes an acceleration signal from the acceleration sensor 25, a rotational speed signal from the front wheel side vehicle speed sensor 21 and the rear wheel side vehicle speed sensor 24, an outside air temperature signal from the outside air temperature sensor 26, a gradient signal from the slope sensor 27, and a drive. Based on the drive mode signal from the mode selection switch 28, the drive mode of the vehicle is determined and a solenoid current command value is output to the electronic control coupling 63.

  The drive mode selection switch 28 is operated in accordance with the “2WD” mode for driving only the two front wheels 65, the “LOCK” mode for driving the front and rear four wheels 65 and 66 regardless of the driving conditions, and the driving conditions. It is a switch for switching between three modes, “AUTO” mode, which switches between a two-wheel drive state and a four-wheel drive state as appropriate, and a desired mode is selected by a driver's operation.

  That is, when the drive mode switch is set to “2WD”, the clutch of the electronic control coupling 63 is released by setting the solenoid current command value to zero, and the driving force of the engine 1 is always 100% on the front wheels. Distributed.

  When the drive mode switch 28 is set to “LOCK”, the solenoid current command value is set to the maximum value, the clutch of the electronic control coupling 63 is completely engaged, and the driving force of the engine 1 is a predetermined value. It is distributed to the front wheel 65 and the rear wheel 66 at a fixed ratio (for example, front wheel: rear wheel = 50: 50).

  Further, when the drive mode switch 28 is set to “AUTO”, the road surface condition is estimated based on the detection value of each sensor, and the driving force distribution to the front and rear wheels 65 and 66 that is optimal for the estimated road surface condition is performed. Is calculated and the solenoid current command value is set. The optimal driving force distribution for the estimated road surface condition is obtained in advance through experiments or the like, and is distributed to the front wheels 65 and the rear wheels 66 at a ratio of 100: 0 to 50:50, for example.

  FIG. 2 is a schematic configuration diagram showing in more detail the configuration from the engine of FIG. 1 to the continuously variable transmission. The belt-type continuously variable transmission 5 includes an input-side primary pulley 10, an output-side secondary pulley 11, and a belt 12 that is wound between both pulleys so that torque can be transmitted. The output shaft of the engine 1 is connected to the primary pulley 10 via the torque converter 7 and the forward / reverse switching mechanism 4 and is output from the secondary pulley 11 to the drive wheel side.

  The forward / reverse switching mechanism 4 includes a planetary gear 40 that switches a power transmission path from the engine 1 to the primary pulley 10, a forward clutch 41, and a reverse clutch 42. The forward clutch 41 is fastened when the vehicle moves forward, the reverse clutch 42 is fastened when the vehicle moves backward, and both the forward clutch 41 and the reverse clutch 42 are released at the neutral position (neutral or parking).

  The forward clutch 41 and the reverse clutch 42 are controlled to be engaged by a clutch pressure adjusting device 30 that supplies a predetermined operating oil pressure to the forward clutch 41 and the reverse clutch 42 in accordance with a command from the control unit 20. The clutch pressure adjusting device 30 adjusts the hydraulic pressure supplied to the forward clutch 41 and the reverse clutch 42 using the hydraulic pressure from the hydraulic pump 15 driven by the driving force of the engine 1 as a source pressure.

  The control unit 20 includes a vehicle speed signal from the front wheel side vehicle speed sensor 21, a range signal from the inhibitor switch 22 responsive to the shift lever, an engine rotation speed signal from the engine 1, and a rotation of the primary pulley 10 from the primary pulley rotation speed sensor 23. A hydraulic pressure command value is determined based on the driving state such as speed and the driving operation, and commanded to the clutch pressure adjusting device 30. The inhibitor switch 22 shows an example of selecting one of forward (D range), neutral position = neutral (N range), and reverse (R range).

  The clutch pressure adjusting device 30 adjusts the hydraulic pressure supplied to the forward clutch 41 and the reverse clutch 42 according to the hydraulic pressure command value, and engages or releases the forward clutch 41 and the reverse clutch 42.

  The forward clutch 41 and the reverse clutch 42 are exclusively engaged, and at the time of forward movement (range signal = D range), the forward clutch pressure is supplied to fasten the forward clutch 41 while the reverse clutch pressure is connected to the drain. Then, the reverse clutch 42 is released. At the time of reverse (range signal = R range), the forward clutch pressure is connected to the drain to release the forward clutch 41, while the reverse clutch pressure is supplied and the reverse clutch 42 is engaged. In the neutral position (range signal = N range), the forward clutch pressure and the reverse clutch pressure are connected to the drain, and both the forward clutch 41 and the reverse clutch 42 are released.

  The primary pulley rotation speed sensor 23 that detects the rotation speed of the primary pulley 10 faces an output gear (not shown) attached to the primary pulley 10, and teeth are formed at equal intervals on the outer periphery of the output gear. . For this reason, the output waveform detected by the primary pulley rotational speed sensor 23 is a pulse having an equal pitch at a constant vehicle speed. That is, the primary pulley rotation speed sensor 23 is configured by a pulse sensor that outputs a pulse signal synchronized with the rotation of the primary pulley 10.

  The vehicle equipped with a continuously variable transmission is configured as described above. When the driver depresses the brake pedal in the D range and the vehicle is stopped, the neutral clutch that releases the forward clutch 41 to reduce the driving load of the engine 1 is achieved. Control is performed. Since it is necessary to immediately engage the forward clutch 41 when the vehicle restarts, the clutch pressure of the forward clutch 41 is controlled to a clutch pressure slightly lower than the clutch pressure at the clutch meet point where the forward clutch 41 starts torque transmission. .

  At this time, if the clutch pressure is too high, the forward clutch 41 is not completely released, so that the forward clutch 41 is dragged and durability is lowered, and the driving load of the engine 1 is not sufficiently reduced. The fuel efficiency improvement effect is suppressed. In addition, if the clutch pressure is too low, the time required to engage the forward clutch 41 when the vehicle is restarted becomes longer, so that the start-up becomes sluggish. Therefore, it is necessary to appropriately set the clutch meet point by learning control.

  Therefore, the clutch meet point is learned by detecting a pulse signal transmitted from the primary pulley rotational speed sensor 23 that detects the rotational speed of the primary pulley 10. Specifically, when the forward clutch 41 reaches a torque capacity at which torque transmission starts from the non-engaged state, the forward clutch 41 is dragged and a small torsional torque is transmitted to the output side (fastened member). Since the (for example, drive shaft) is twisted, this is detected by the primary pulley rotational speed sensor 23 and a pulse signal is output to the control unit 20. Based on the input pulse signal, the control unit 20 learns a clutch meet point at which the forward clutch 41 starts to transmit torque. Since the vehicle is stopped by the driver depressing the brake pedal at the time of the control, even if the engine torque is transmitted to the output side via the forward clutch 41 and the drive shaft is twisted, the front and rear wheels 65, 66 does not rotate.

  However, in the four-wheel drive vehicle, the inertia of the shafts between the forward clutch 41 and the drive wheels 65 and 66 is larger than that in the two-wheel drive vehicle, so that the torsional rigidity is increased correspondingly and the output side of the forward clutch 41 is increased. The amount of torsional displacement is reduced. Accordingly, since the rotational displacement of the primary pulley 10 due to twisting is also reduced, the pulse of the primary pulley rotation speed sensor 23 is hardly generated. As a result, the time during which the forward clutch 41 is held in the drag state during learning of the clutch meet point that is performed until a pulse is detected becomes longer, and the durability of the forward clutch 41 may be reduced.

  Therefore, in the present embodiment, the following control is performed during clutch meet point learning. FIG. 3 is a flowchart showing the control of the continuously variable transmission-equipped vehicle in the present embodiment.

  In step S1, it is determined whether or not neutral control is being performed. If it is determined that the neutral control is being performed, the process proceeds to step S2, and if it is determined that the neutral control is not being performed, the process is terminated. Neutral control is control that reduces the driving load of the engine 1 by disengaging the forward clutch 41, and is performed while the vehicle is stopped in the D range.

  In step S2, it is determined whether or not the clutch meet point learning control is completed. If it is determined that the clutch meet point learning control has been completed, the process ends. If it is determined that the clutch meet point learning control has not been completed, the process proceeds to step S3.

  The clutch meet point learning control is a control for learning the clutch pressure at the clutch meet point at which the forward clutch 41 starts torque transmission. When the clutch meet point learning control is repeatedly performed a predetermined number of times in one driving cycle, it is determined that the learning control is completed. Alternatively, it may be determined that the learning control has been completed when it is repeatedly performed a predetermined number of times while traveling a predetermined distance instead of one driving cycle. The predetermined number of times is a number that can improve the accuracy of learning control, and is obtained in advance by experiments or the like. Details of the clutch meet point learning control will be described later.

  In step S3, it is determined whether or not the vehicle is in a four-wheel drive state. If it is determined that the vehicle is in the four-wheel drive state, the process proceeds to step S4. If it is determined that the vehicle is in the two-wheel drive state, the process proceeds to step S6. When the drive mode selection switch is in the “AUTO” mode and the solenoid current command value is not zero, or when the drive mode selection switch is set in the “LOCK” mode, it is determined that the vehicle is in the four-wheel drive state.

  In step S4, it is determined whether or not the vehicle can be started even in a two-wheel drive state when the vehicle restarts. If it is determined that the vehicle can be started even in the two-wheel drive state, the process proceeds to step S5. If it is determined that the vehicle cannot start in the two-wheel drive state, the process is terminated.

  When the drive mode selection switch 28 is set to the “AUTO” mode, it detects whether or not the vehicle is traveling on a rough road based on a change in the acceleration of the vehicle detected by the acceleration sensor 25, and the front and rear wheels 65, Based on the difference in rotational speed of 66, it is detected whether the vehicle is traveling on a low μ road, whether the road surface is frozen based on the outside air temperature sensor 26, and based on the detected value of the gradient sensor 27. The road surface gradient is determined, and based on these results, it is determined whether or not the vehicle can start even in a two-wheel drive state. The detection or determination is always performed while the vehicle is traveling, and in this step, it is determined whether or not the vehicle can be started even in the two-wheel drive state based on the determination immediately before the vehicle stops.

  Further, when the drive mode selection switch 28 is set to the “LOCK” mode, it is determined that the driver is traveling on a rough road, and therefore it is determined that the vehicle cannot start in the two-wheel drive state. .

  In step S5, the driving state of the vehicle is switched from the four-wheel driving state to the two-wheel driving state. The switching is performed by setting the solenoid current command value to the electronic control coupling 63 to zero.

  In step S6, clutch meet point learning control is performed. The clutch meet point learning control will be described later.

  In step S7, the driving state of the vehicle is switched from the two-wheel driving state to the four-wheel driving state. The switching is performed by resetting the solenoid current command value to the electronic control coupling 63 to a value before executing step S5.

  If there is a vehicle start request between the switch to the two-wheel drive state in step S5 and the return to the four-wheel drive state in step S7, the vehicle is started in the two-wheel drive state, and then 4 Switch to wheel drive mode. At this time, the startability of the vehicle can be ensured by restricting the engine torque to a torque that can transmit the driving force to the road surface even in a two-wheel drive state.

  Here, the clutch meet point learning control performed in step S6 will be described with reference to FIG. FIG. 4 is a time chart showing the clutch meet point learning control, where (a) is the clutch command pressure, (b) is the forward clutch transmission torque, (c) is the output pulse of the primary pulley rotation speed sensor, and (d) is The turbine rotation speed, which is the rotation speed on the input side of the forward clutch, is shown.

  At time t1, the clutch command pressure for engaging the forward clutch 41 during the neutral control is increased stepwise with a predetermined hydraulic pressure.

  At time t2, torque starts to be transmitted to the output side of the forward clutch 41, the turbine rotational speed of the torque converter 7 decreases, and the forward clutch 41 switches from the non-engaged state to the engaged state. The clutch command pressure at the time of switching to the engaged state becomes the clutch meet point.

  At time t3, the primary pulley rotational speed sensor 23 detects the twist on the output side of the forward clutch 41 and outputs it to the control unit 20 as a pulse signal. The control unit 20 stores the clutch command pressure learning value corresponding to the clutch meet point based on the clutch command pressure at the time when the first pulse signal is input after increasing the clutch command pressure. Here, the differential pressure between the clutch command pressure when the pulse signal of the primary pulley rotation speed sensor 23 is output and the clutch command pressure corresponding to the clutch meet point is obtained in advance by experiments or the like. The differential pressure is set so that the clutch command pressure is slightly lower than the clutch command pressure corresponding to the clutch meet point at which torque transmission starts by a predetermined hydraulic pressure, and the forward clutch 41 is in the non-engaged state. To improve fuel efficiency.

  After time t3, the clutch command pressure is controlled based on the stored clutch command pressure learning value, and neutral control is performed. Note that learning from time t1 to t3 is continuously performed a plurality of times, and the clutch instruction pressure learning value at the time of detecting the pulse signal in each learning period can be averaged to obtain the final clutch instruction pressure learning value. .

  Next, the operation of the continuously variable transmission vehicle according to this embodiment will be described with reference to FIG. FIG. 5 is a time chart showing the operation of the vehicle equipped with a continuously variable transmission according to the present embodiment. The driving state, (d) shows the clutch meet point learning control state.

  While the vehicle is traveling in a four-wheel drive state, the driver decelerates by depressing the brake pedal, and when the vehicle stops at time t1, neutral control is started. At this point, since it is determined that the vehicle can start even in the two-wheel drive state when the vehicle restarts, that is, the four-wheel drive state is unnecessary, the drive state is switched to the two-wheel drive state and the clutch meet point Perform learning control.

  When clutch meet point learning control is completed at time t2, the driving state is switched from the two-wheel driving state to the four-wheel driving state.

  Thereafter, when the driver depresses the accelerator pedal at time t3, the vehicle restarts in a four-wheel drive state.

  As described above, in this embodiment, in a vehicle that can travel in a four-wheel drive state, when the drive state at the start of neutral control is the four-wheel drive state, it is necessary to restart in the four-wheel drive state when the vehicle restarts. If it is determined that it is not necessary, the clutch meet point learning control is performed after switching the driving state to the two-wheel driving state, so the inertia on the output side of the forward clutch 41 during the learning control is reduced. It can be made smaller than that in the four-wheel drive state, and the rotation of the primary pulley 10 can be detected earlier by reducing the inertia. As a result, the time during which the forward clutch 41 is held in the drag state can be shortened as compared with the case where learning control is performed in the four-wheel drive state, so that appropriate learning control can be performed without being affected by the increase in inertia. In addition, it is possible to prevent the durability of the forward clutch 41 from being lowered (corresponding to claims 1, 2, 6 and 7).

  When it is determined that the clutch meet point learning control has been repeatedly performed a predetermined number of times, the switching of the driving state is stopped and the clutch meet point learning control is stopped, so unnecessary learning control is performed while improving the accuracy of the learning control. It is possible to suppress the deterioration of the startability of the vehicle (corresponding to claim 3).

  Further, when it is determined that it is necessary to start in the four-wheel drive state when the vehicle restarts, the clutch meet point learning control is stopped, so that the four-wheel drive state is changed in a road surface situation where starting in the two-wheel drive state is difficult. It is maintained, and the startability of the vehicle can be prevented from deteriorating (corresponding to claim 4).

  When the vehicle is requested to start while switching to the two-wheel drive state and performing the clutch meet point learning control, the vehicle is started in the two-wheel drive state. The vehicle can be started and deterioration of the startability of the vehicle can be prevented (corresponding to claim 5).

  The present invention is not limited to the embodiment described above, and various modifications and changes can be made within the scope of the technical idea.

  For example, in this embodiment, when the forward clutch 41 is in the non-engaged state by neutral control, the clutch pressure is gradually increased, and the primary pulley rotation speed sensor 23 emits while shifting from the non-engaged state to the engaged state. The clutch meet point learning control is performed by detecting the pulse. On the contrary, when the forward clutch 41 is shifted from the engaged state to the non-engaged state by the neutral control, the pulse of the primary pulley rotational speed sensor 23 is detected. May be detected. In this case, since the return of the torsional deformation occurs on the output side of the forward clutch 41 as the forward clutch 41 changes from the engaged state to the non-engaged state, a pulse is generated when the primary pulley 10 rotates due to this return. Is detected.

  In the present embodiment, the clutch meet point learning control of the forward clutch 41 has been described as a premise. However, the present invention is not limited to this. For example, the same effect can be obtained even when the clutch meet point learning control of the reverse clutch 42 is performed. be able to.

  Further, in the present embodiment, the belt 12 is described as an example of the winding member wound around the primary pulley 10 and the secondary pulley 11, but the belt 12 is, for example, a notch in which a large number of link plates overlap each other. You may comprise the link plate chain etc. which were combined with the joint type via the pin pushed in.

1 Engine 10 Primary pulley 11 Secondary pulley 12 Belt (winding member)
20 Control unit 23 Primary pulley rotation speed sensor (rotation detection means)
41 Forward clutch (clutch)
65 Front wheel 66 Rear wheel S3 Four-wheel drive necessity determination means S5 Drive state switching means S6 Clutch meet point learning control means

Claims (7)

A continuously variable transmission including a primary pulley to which driving force of an engine is input, a secondary pulley that outputs the driving force to driving wheels, and a primary pulley and a winding member that is wound around the secondary pulley; ,
A clutch capable of selectively transmitting a driving force from the engine to the primary pulley according to a supply hydraulic pressure;
In a vehicle equipped with a continuously variable transmission capable of switching between a two-wheel drive state for driving a front wheel or a rear wheel and a four-wheel drive state for driving the front wheel and the rear wheel,
Rotation detection means for detecting rotation of the primary pulley;
Neutral control for controlling the clutch to a non-engaged state until the vehicle re-starts when the vehicle enters a predetermined state in which the vehicle is stopped with a travel range in which the clutch is held in an engaged state selected Means,
Determining whether four-wheel drive is necessary or not when determining whether or not it is necessary to start in the four-wheel drive state when the vehicle restarts when the drive state when the vehicle enters the predetermined state is the four-wheel drive state Means,
Drive state switching means for switching the drive state to a two-wheel drive state when it is determined that it is not necessary to start in a four-wheel drive state when the vehicle restarts;
After the driving state is switched to the two-wheel driving state, the rotation detecting unit detects the rotation of the primary pulley while changing the clutch controlled to the non-engaged state by the neutral control unit to the engaged state. A clutch meet point learning control unit that learns and controls the supply hydraulic pressure when the clutch switches from the non-engaged state to the engaged state based on the supplied hydraulic pressure at the time when the rotation is first detected;
A vehicle equipped with a continuously variable transmission. A continuously variable transmission including a primary pulley to which driving force of an engine is input, a secondary pulley that outputs the driving force to driving wheels, and a primary pulley and a winding member that is wound around the secondary pulley; ,
A clutch capable of selectively transmitting a driving force from the engine to the primary pulley according to a supply hydraulic pressure;
In a vehicle equipped with a continuously variable transmission capable of switching between a two-wheel drive state for driving a front wheel or a rear wheel and a four-wheel drive state for driving the front wheel and the rear wheel,
Rotation detection means for detecting rotation of the primary pulley;
Neutral control for controlling the clutch to a non-engaged state until the vehicle re-starts when the vehicle enters a predetermined state in which the vehicle is stopped with a travel range in which the clutch is held in an engaged state selected Means,
Determining whether four-wheel drive is necessary or not when determining whether or not it is necessary to start in the four-wheel drive state when the vehicle restarts when the drive state when the vehicle enters the predetermined state is the four-wheel drive state Means,
Drive state switching means for switching the drive state to a two-wheel drive state when it is determined that it is not necessary to start in a four-wheel drive state when the vehicle restarts;
After the drive state is switched to the two-wheel drive state, the rotation detection means detects the rotation of the primary pulley while controlling the clutch to the non-engaged state by the neutral control means. Clutch meet point learning control means for learning and controlling the supply oil pressure when the clutch switches from the non-engaged state to the engaged state based on the supplied oil pressure at the detected time point;
A vehicle equipped with a continuously variable transmission. Learning control number determination means for determining whether or not the learning control has been repeatedly performed a predetermined number of times;
When it is determined that the learning control has been repeatedly performed a predetermined number of times, the driving state switching unit stops switching the driving state to the two-wheel driving state, and the clutch meet point learning control unit stops the learning control. A vehicle equipped with a continuously variable transmission according to claim 1 or 2.   The clutch meet point learning control means stops the learning control when the four-wheel drive necessity determining means determines that it is necessary to start in a four-wheel drive state when the vehicle restarts. A vehicle equipped with a continuously variable transmission according to any one of claims 1 to 3.   When it is determined that it is not necessary to start in the four-wheel drive state when the vehicle restarts, and the vehicle is requested to start when the learning control is performed after switching the drive state to the two-wheel drive state The vehicle with a continuously variable transmission according to any one of claims 1 to 4, wherein the vehicle is started with the driving state being in a two-wheel driving state. A continuously variable transmission including a primary pulley to which driving force of an engine is input, a secondary pulley that outputs the driving force to driving wheels, and a primary pulley and a winding member that is wound around the secondary pulley; ,
A clutch capable of selectively transmitting a driving force from the engine to the primary pulley according to a supply hydraulic pressure;
Comprising: a continuously variable transmission-equipped vehicle control method capable of switching between a two-wheel drive state for driving a front wheel or a rear wheel and a four-wheel drive state for driving the front wheel and the rear wheel,
Detecting rotation of the primary pulley;
Controlling the clutch to a non-engaged state until the vehicle restarts when the vehicle enters a predetermined state in which the vehicle is stopped with a travel range in which the clutch is held in an engaged state selected. ,
Determining whether or not it is necessary to start in the four-wheel drive state when the vehicle restarts when the vehicle is in the four-wheel drive state when the vehicle is in the predetermined state;
When it is determined that it is not necessary to start in a four-wheel drive state when the vehicle restarts, the step of switching the drive state to a two-wheel drive state;
After the driving state is switched to the two-wheel driving state, the rotation of the primary pulley is detected by the detecting step while changing the clutch controlled to the non-engaged state by the controlling step to the engaged state. Learning control of the supply hydraulic pressure when the clutch switches from the non-engaged state to the engaged state based on the supplied hydraulic pressure at the time when the rotation is first detected;
A control method for a vehicle equipped with a continuously variable transmission. A continuously variable transmission including a primary pulley to which driving force of an engine is input, a secondary pulley that outputs the driving force to driving wheels, and a primary pulley and a winding member that is wound around the secondary pulley; ,
A clutch capable of selectively transmitting a driving force from the engine to the primary pulley according to a supply hydraulic pressure;
Comprising: a continuously variable transmission-equipped vehicle control method capable of switching between a two-wheel drive state for driving a front wheel or a rear wheel and a four-wheel drive state for driving the front wheel and the rear wheel,
Detecting rotation of the primary pulley;
Controlling the clutch to a non-engaged state until the vehicle restarts when the vehicle enters a predetermined state in which the vehicle is stopped with a travel range in which the clutch is held in an engaged state selected. ,
Determining whether or not it is necessary to start in the four-wheel drive state when the vehicle restarts when the vehicle is in the four-wheel drive state when the vehicle is in the predetermined state;
When it is determined that it is not necessary to start in a four-wheel drive state when the vehicle restarts, the step of switching the drive state to a two-wheel drive state;
After the driving state is switched to the two-wheel driving state, the rotation of the primary pulley is detected by the detecting step while controlling the clutch to the non-engaged state by the controlling step. Learning control of the supply hydraulic pressure when the clutch switches from the non-engaged state to the engaged state based on the supplied hydraulic pressure at the detected time;
A control method for a vehicle equipped with a continuously variable transmission.