JP3350220B2 - Vehicle control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a vehicle in which an automatic clutch and a continuously variable transmission are combined. More specifically, the power supply of a control unit is turned off during running and then turned on again. Regarding measures in case.

[0002]

2. Description of the Related Art For example, there has been known a vehicle using an electromagnetic clutch as an automatic clutch and combining the electromagnetic clutch with a belt-type continuously variable transmission. In this vehicle, the control unit is operated by an ignition power supply or a battery power supply that is supplied when the ignition power supply is turned on. The control unit controls an actuator such as a solenoid valve to control the hydraulic pressure, and the input side pulley (hereinafter referred to as primary pulley) and the output side pulley (hereinafter referred to as secondary pulley) control the speed ratio by adjusting the force for pinching the belt. . Also, the clutch is controlled to ON / OFF / slip by controlling the clutch current for exciting the electromagnetic clutch.

Therefore, in the electronic control system of a vehicle, it is required that power is always supplied to the control unit while the vehicle is running. However, during traveling, the power supply may be turned off due to poor contact of the power supply system connector or intentional operation of the driver. In this case, the control unit stops functioning when the power is turned off, and the continuously variable transmission as described above temporarily enters a non-control state. Thereafter, when the control unit recovers its function when the power is turned on, the control unit performs electrical processing again and returns to a normal state. Also, in the case of the electromagnetic clutch, when the power is off, the clutch current does not flow, so that the electromagnetic clutch is temporarily disconnected, and the power supply is turned off.
When the control unit recovers its function at N, it is immediately connected because it is running.

[0004] Therefore, immediately after the power is turned off and then on during traveling, the electromagnetic clutch is engaged before the speed change control of the continuously variable transmission returns to normal, and the actual speed ratio at this time becomes the maximum speed ratio (LOW). If it is close to, excessive engine braking may be applied, and the safety of the vehicle may be impaired. Therefore, when the power supply is turned off → on while the vehicle is running, it is desired to control the electromagnetic clutch and the continuously variable transmission so as to prevent abrupt engine braking.

[0005] Conventionally, as for the control of the automatic clutch and the continuously variable transmission, for example, there is a prior art disclosed in Japanese Patent Application Laid-Open No. 62-160932.
The primary engine speed follows the increase in engine speed,
It is shown that the clutch is engaged when the engine speed substantially coincides with the primary speed. Also, JP-A-63
In the prior art disclosed in Japanese Patent No. 1766751, the engagement completion input-side rotation speed is set first to complete the engagement of the clutch at this rotation speed, and then the target input-side rotation speed that matches the engagement completion input-side rotation speed is set. It is shown that the speed ratio of the continuously variable transmission is controlled so that the actual input side rotation speed matches, and furthermore, the engagement completion input side rotation speed and the target input side rotation speed are matched when the clutch engagement is completed. I have.

[0006]

In any of the above-mentioned prior arts, the rotation of the input side and the output side during engagement of the clutch is assumed on the assumption that the control unit is normally started. In this configuration, the numbers are made to match by speed change control. This is also clutch control when starting. For this reason, as the object of the present invention, it cannot be applied to clutch control when the power supply of the control unit is turned off during running and then turned on again.

[0007]

According to the present invention, a continuously variable transmission is connected to an engine via an automatic clutch, and the automatic clutch is automatically connected and disconnected based on various vehicle information. And a control device for a vehicle including a control unit that controls the speed of the continuously variable transmission.
The control unit stores history information based on various vehicle body information at the time of power-on, and power-supply-interruption determining means for determining a power interruption during traveling based on the stored history information. A shift control normal return determining unit that determines that the shift control of the continuously variable transmission has returned to a normal state after an instantaneous power interruption, and the automatic clutch when the instantaneous power interruption determining unit determines an instantaneous power interruption during traveling. And a clutch connection prohibition unit that holds the automatic clutch in a disengaged state until the shift control normal return determination unit determines that the shift control of the continuously variable transmission is normal. .

[0008]

According to the present invention, a continuously variable transmission 4 is connected to an engine 1 via an automatic clutch 2 as shown in FIG. Automatic clutch 2 by 40 electric signals
Is automatically turned off and the speed of the continuously variable transmission 4 is controlled. When the power of the control unit 40 is turned on, an instantaneous power cut during running is determined based on the history of the first calculation value of the input signal. Determination means 41 and shift control normal return determination means 42 for determining normal return of the shift control of the continuously variable transmission 4
And a clutch connection prohibiting means 43 for prohibiting the connection of the automatic clutch 2 until the speed change control of the continuously variable transmission 4 returns to normal in the case of a momentary power interruption during running.

In the present invention, the normal return of the shift control of the continuously variable transmission when the power supply of the control unit is turned on after the power supply is momentarily interrupted during traveling is a state in which the actual gear ratio follows the target gear ratio, and after the power is turned on. The determination can be made at a certain time corresponding to the maximum value of the time required for the actual gear ratio to converge to the target gear ratio, but is not limited to this. The target gear ratio in this case may be a gear ratio according to the running state, but may be set to the overdrive side to reduce engine braking and the like.

In the present invention, when the time from the start of the normal engine to the start of running is longer than the time corresponding to the maximum value of the time required for the actual speed ratio after power-on to converge on the target speed ratio. In this case, it is also possible to omit the instantaneous interruption of power supply during traveling and to control so that the clutch connection is always prohibited for a predetermined time based on the traveling start time when the control unit is powered on.

Further, in the present invention, the automatic clutch can be applied to an electromagnetic clutch or a clutch having another configuration. The continuously variable transmission can be applied to a belt-type continuously variable transmission or a continuously variable transmission having another configuration.

[0012]

According to the present invention having the above-described structure, in a vehicle in which the continuously variable transmission 4 is connected to the engine 1 via the automatic clutch 2, the single control unit 40 is turned on to operate the automatic clutch 2. Control and continuously variable transmission 4
Is electronically performed. Then, the automatic clutch 2 is automatically disengaged or connected in accordance with the driving or running state, and the continuously variable transmission 4 similarly performs a continuously variable transmission in accordance with the driving or running state and travels.

When the control unit 40 is powered on,
For example, only the first calculation result is stored as the calculation history of the input signal by the instantaneous power interruption determining means 41, and the control unit 40 normally turns on when the vehicle is stopped based on the calculation result.
And the control unit 40
It is determined that the power supply has been momentarily interrupted and turned on again. Then, in the case of a momentary power interruption, the automatic clutch 2 which has been in the disconnected state due to the power OFF is held in the disconnected state by the clutch connection inhibiting means 43.

[0014] In the power supply - stop times continuously variable transmission 4 of the control unit 40 temporarily becomes uncontrolled, transmission control function and the like works normally after power ON. That is, the target speed ratio is set, and the speed change is controlled so that the actual speed ratio follows the target speed ratio. Therefore, the shift control normal return determination means 42 determines the restart state of the shift control based on the coincidence of the target speed ratio and the actual speed ratio in this case, the lapse of time when both converge, and the like. For example, when the target speed ratio and the actual speed ratio match,
It is determined that the shift control has been restarted, and the automatic clutch 2 is released by the clutch connection prohibiting means 43 to be connected. Therefore, when the power of the control unit 40 is turned on while the vehicle is running, the automatic clutch 2 is controlled to be engaged when the actual speed ratio of the continuously variable transmission 4 substantially converges to a target corresponding to the running state. The occurrence of braking is avoided beforehand.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. Referring to FIG. 2, an overall configuration of a drive system of a vehicle in which a belt-type continuously variable transmission is combined with an electromagnetic clutch will be described. The engine 1 includes an electromagnetic clutch 2 and a forward / reverse switching device 3
, And is transmitted to the drive wheels 9 from the continuously variable transmission 4 via a set of reduction gears 5, an output shaft 6, a differential device 7, and an axle 8.

The electromagnetic clutch 2 has a drive member 2a directly connected to the crankshaft 10 of the engine 1, and a driven member 2b having a built-in clutch coil 2c and directly connected to the input shaft 11. When the clutch current Ic is supplied to the clutch coil 2c by the control unit 40, the magnetic powder is magnetically coupled to the gap between the two members 2a, 2b in a chain-like manner and accumulated, and the clutch torque is changed by this coupling force. .

The forward / reverse switching device 3 is constituted by a gear, a hub and a sleeve between the input shaft 11 and the primary shaft 12 in a synchronous meshing manner. Then, the input shaft 11 is changed to the primary shaft 12
A forward position directly connected to the input shaft 11, a reverse position for reversing the rotation direction of the input shaft 11 and transmitting the rotation to the primary shaft 12,
12 has a neutral position for cutting.

The continuously variable transmission 4 has a primary shaft 12 and a secondary shaft 13 arranged in parallel with the primary shaft 12. The primary shaft 12 is provided with a primary pulley 14 having a primary cylinder 14a and a variable pulley interval. The secondary shaft 13 is provided with a secondary pulley 15 having a similar secondary cylinder 15a.
The drive belt 16 is wound therebetween.

Next, the hydraulic control system will be described. First, an oil passage 22 from an oil pump 21 communicating with an oil pan 20 communicates with a secondary pressure control valve 26. When the solenoid current Is flows from the control unit 40, the secondary pressure control valve 26 adjusts the pump discharge pressure to generate a predetermined secondary pressure (line pressure) Ps. To provide a clamping force corresponding to the transmission torque. The secondary pressure Ps is transmitted through the oil passage 24 to the transmission control valve 2.
It is led to 7. When the solenoid current Ip from the control unit 40 flows, the shift control valve 27
Is supplied to and discharged from the primary cylinder 14a to generate a predetermined primary pressure Pp. With this primary pressure Pp, the ratio of the winding diameter of the drive belt 16 to both the pulleys 14 and 15 is changed to perform stepless speed change control. Be composed.

Further, the electronic control system will be described. The control unit 40 has both a clutch control function, a shift control function, and a secondary pressure control function, and has an arithmetic function and an input / output function necessary for each control. When the engine is operated by turning on the ignition switch 35, power is supplied from the battery 36, and the microcomputer of the control unit 40 operates. A secondary pressure sensor 30 for detecting the secondary pressure Ps, an engine speed sensor 31 for detecting the engine speed Ne by an ignition pulse or the like, a primary pulley speed sensor 32 for detecting the primary pulley speed Np, and a secondary pulley speed Ns. Secondary pulley rotation speed sensor 3 to detect
3. Throttle sensor 3 for detecting throttle opening θ
4. It has various switches 37 such as a range switch, an accelerator switch, and a brake switch. These various car bodies
A signal as information is input to the control unit 40 and is electrically processed, the clutch current Ic is output to the electromagnetic clutch 2 to perform clutch control, and the solenoid current Is is output to the secondary pressure control valve 26 to perform secondary pressure control. Then, the solenoid current Ip is output to the shift control valve 27 to perform shift control.

Next, the operation of this embodiment will be described with reference to the flowcharts of FIGS. First, when the vehicle is stopped, the ignition switch 35 is turned on to set the engine 1
Is started, the oil pump 21 is driven by the engine 1 to generate a hydraulic pressure, and the hydraulic pressure is guided to the secondary pressure control valve 26. The control unit 40 includes a battery 36
, Power is turned on, and clutch control, shift control, and secondary pressure control are executed.

The clutch control will be described with reference to the flowchart of FIG. This flowchart is executed at predetermined time intervals. In step S1, it is determined whether the vehicle speed Vs obtained from the secondary pulley rotation speed Ns is larger or smaller than a set value. The degree of opening θ is determined, and if it is a fully closed opening degree, the target clutch torque Tc is set to T in step S5.
c = 0, and the clutch current Ic is set in step S6.
Set Ic = 0 to disengage the clutch. Therefore, when the vehicle is stopped with the throttle fully closed, the electromagnetic clutch 2 is automatically disconnected.

When, for example, the D range is selected at the time of starting, the forward / reverse switching device 3 is at the forward position, and the input shaft 11 and the primary shaft 12 are directly connected. Then, when the accelerator is depressed, the process proceeds from step S2 to S4, where the target clutch torque Tc is set so as to gradually increase as a function of the engine speed Ne, and the torque in the half-clutch state is set. In step S6, the clutch current Ic is converted into a clutch current Ic corresponding to the half-clutch torque.
And control. Therefore, a clutch current Ic corresponding to the increase in the engine speed Ne flows through the electromagnetic clutch 2, and
The electromagnetic clutch 2 connects smoothly. Therefore, the power of the engine 1 is input to the continuously variable transmission 4 via the electromagnetic clutch 2 and the forward / reverse switching device 3, and the power of the maximum speed ratio is transmitted to the drive wheels 9 and the vehicle starts running.

When the vehicle speed Vs becomes equal to or higher than the set value after the vehicle starts running, the process proceeds from step S1 to step S3, in which the target clutch torque Tc is set to a direct coupling torque equal to or higher than the engine maximum output torque. Is controlled to a large value. Therefore, the electromagnetic clutch 2 is securely connected, and is kept connected thereafter. When the vehicle speed decreases during deceleration and the vehicle speed Vs falls below the set value, the process proceeds from step S1 to step S2 again, and when the throttle is fully closed, the process further proceeds to step S5 and thereafter to automatically disengage the clutch and prevent engine stall. . This clutch control corresponds to "normal clutch control" in the flowcharts of FIGS.

The secondary pressure control will be described with reference to the flowchart of FIG. This flowchart is also executed at predetermined time intervals. First, in step S11, the engine torque Te is changed to the throttle opening θ and the engine speed Ne.
Is estimated by a map search. Further, the actual speed ratio i is calculated by i = Np / Ns from the primary pulley rotation speed Np and the secondary pulley rotation speed Ns.

In step S12, a secondary pressure Psu required for transmitting the unit torque is obtained by a function with the actual speed ratio i. Thereafter, the process proceeds to step S13, where the target secondary pressure Pss is obtained. That is, by multiplying the input pressure Te by the secondary pressure Psu necessary for transmitting the unit torque, the secondary pressure required at that time is obtained. Therefore, the target secondary pressure Pss is calculated from Pss = Ksf × Te × Psu based on the secondary pressure Psu, the input torque Te and a slight safety factor Ksf (where Ksf> 1.0).

Further, the routine proceeds to step S14, where the current is converted into a solenoid current Is corresponding to the target secondary pressure Pss.
At this time, the feedback amount (Ps−Ps) based on the actual secondary pressure Ps detected by the secondary pressure sensor 30
s), the solenoid current Is is calculated as Is = f2 (P
ss) + f3 (Ps-Pss). Then, the solenoid current Is is output to the secondary pressure control valve 26.

Therefore, when the vehicle stops at Ns = 0, the actual gear ratio i
Becomes the maximum speed ratio and the required secondary pressure hydraulic pressure Psu also increases, but the target secondary pressure Pss is calculated to be low because the engine torque Te is small when the throttle is fully closed.
When the engine torque Te increases in accordance with the depression of the accelerator at the time of starting, the target secondary pressure Pss increases. If the actual gear ratio i gradually decreases due to the increase in Ns during the running after the start and the required secondary pressure Psu decreases, and when the engine torque Te further decreases,
Control is performed such that the target secondary pressure Pss becomes lower again.

Then, a solenoid current Is corresponding to the target secondary pressure Pss flows to the secondary pressure control valve 26, and the secondary pressure Ps of the secondary cylinder 15a is controlled according to the transmission torque in each running state. Therefore, the belt clamping force by the secondary pulley 15 is controlled so as to secure the minimum clamping force that does not cause belt slip with respect to the transmission torque. In addition, the feedback of the difference between the actual secondary pressure Ps and the target secondary pressure Pss is added to the solenoid current Is, so that the secondary pressure Ps is maintained at the target secondary pressure Pss even when the shift speed is high.
And a proper clamping force is secured.

The shift control will be described with reference to the flowchart of FIG. This flowchart is also executed at predetermined time intervals. First, in step S21, the throttle opening θ
-The target speed ratio is is calculated and determined from is = Npd / Ns from the target primary pulley rotation speed Npd and the secondary pulley rotation speed Ns which are map-defined as a function of the vehicle speed Vs.

In step S22, a primary pressure Ppd necessary for achieving the target gear ratio is is calculated. Maximum torque that can be transmitted with the current secondary pressure Ps (Ps / Ps
u) and the engine torque Te are represented by Kt, and the target gear ratio is
Is defined as Ppd, and K
t = Te / (Ps / Psu), Kp = f4 (Kt / i
s), required primary pressure Pp by Ppd = Kp × Ps
Find d.

Thereafter, the process proceeds to step S23, where the target primary pressure Pps is calculated from Pps = Ppd ± ΔPp by the correction ΔPp corresponding to the difference between the target speed ratio is and the actual speed ratio i. Further, in step S24, the current is converted into a solenoid current Ip corresponding to the target primary pressure Pps, and this solenoid current Ip is output to the shift control valve 27.

Therefore, when the vehicle stops at Ns = 0, the target speed ratio is set to the maximum speed ratio of the continuously variable transmission 4 on the mechanism.
By operating the shift control valve 27 to the drain (oil drainage) side, the primary pressure Pp becomes substantially zero. For this reason, the secondary syringe 1
5a is supplied with the secondary pressure Ps, and the continuously variable transmission 4
Is the low speed stage having the maximum speed ratio at which the belt 16 moves to the secondary pulley 15 side most. When traveling after starting, θ-
The target primary pulley rotation speed Npd is set according to the driving and running conditions according to the map of Vs, and the target speed ratio is is sequentially reduced as the secondary pulley rotation speed Ns increases together with the vehicle speed Vs to start shifting. Then, the target primary pressure Pp is determined by the torque ratio Kt, the hydraulic pressure ratio Kp, and the correction ΔPp corresponding to the deviation between the actual speed ratio i and the target speed ratio is.
s is calculated to be gradually higher. Therefore, the solenoid current Ip to the shift control valve 27 also gradually changes to the pressure increasing side, and accordingly, the oil supply amount is increased by the shift control valve 27 so that the primary pressure Pp is controlled to be sequentially increased, and the belt 16 is moved toward the primary pulley 14. To upshift to a higher gear with a smaller gear ratio. Then, it is possible to shift to the overdrive having the minimum speed ratio and to run at high speed.

If the target primary pulley rotation speed Npd increases when the accelerator pedal is depressed, or if the vehicle speed Vs drops below the set value during deceleration, the target gear ratio is increases and the gear shifts down. In this way, the actual speed ratio i follows the target speed ratio is between the maximum speed ratio and the minimum speed ratio, and upshifting or downshifting is performed, thereby performing stepless speed change control.

Next, when the control unit 40 normally turns on the power when the vehicle is stopped, and when the power is turned off for some reason during running.
Next, control in the case of an instantaneous interruption that is turned on after that is described. Here, when the power supply of the control unit 40 is turned off, the electromagnetic clutch 2 is not energized and is in a disconnected state. In addition, the secondary pressure control and the shift control of the continuously variable transmission control system are not performed, and the vehicle is in a non-control state when the vehicle is traveling. However, a fail-safe function is provided to ensure traveling performance when the electronic control system fails. ing. That is, as the shift control valve 27 and the secondary pressure control valve 26, valves that reduce the pressure when the solenoid currents Ip and Is increase are used. Therefore, the power supply O
In the FF, both valves 26 and 27 are operated on the pressure increasing side. In this embodiment, the primary pressure and the secondary pressure are the respective maximum pressures. In many cases, however, the FF is designed to have an intermediate speed ratio. Therefore, during traveling in the overdrive area, the power supply OF
When the vehicle is in the non-control state at F, a downshift operation is performed and abrupt engine braking is caused.

Therefore, as a solution to the above-mentioned problems, the control unit 40 determines whether the power supply is running while the vehicle is running, and determines an instantaneous power interruption, and forcibly engages the clutch when the power is running. Has a function of clutch connection prohibition control for prohibiting the clutch connection. These controls are executed during traveling by the engine operation.

The instantaneous interruption determination control will be described with reference to the flowcharts of FIGS. Operation sub routine in FIG. 6, the engine speed, the primary pulley rotational speed, the secondary pulley rotational speed, illustrates a general form of a subroutine program for calculating the input value of the secondary hydraulic pressure and the like. Therefore, in step S31, when the power supply of the control unit 40 is turned on, the rotational speed of the secondary pulley and the rotational speed of the wheel side of the vehicle speed are calculated. Thereafter, the process proceeds to step S32 to check the operation history flag. In the case of the first time, the operation proceeds to step S33, where the operation value at this time is stored and stored in the memory, and the operation proceeds to step S34 to set the operation history flag. Then, after the second time, the process directly exits from step S32, and thus the power is turned on, and information such as the wheel-side rotation speed for the first time is obtained.

In the instantaneous interruption determination subroutine of FIG. 7, the first initial operation value is compared with a threshold value in step S41. If the difference is smaller than the threshold value, the process directly exits. If the difference is larger than the threshold value, a momentary power interruption is determined, and the process proceeds to step S42 to set the momentary power interruption flag.

Therefore, while the vehicle is stopped, the ignition switch 3
5 and ON the Rutotomoni control unit 4 to the engine start
When the power is normally turned on at 0, the wheel-side rotation speed of the first initial calculation value is substantially zero. For this reason, the initial calculation value is smaller than the threshold value and exits as it is, and it is determined that the power is turned on while the vehicle is stopped. On the other hand, when the power of the control unit 40 is turned off → on for some reason during traveling, the wheel-side rotation speed of the initial calculation value becomes larger than the threshold value according to the traveling state in this case, and thus the instantaneous power Disconnection is determined.

The clutch connection prohibition control will be described with reference to the clutch control subroutine in the flowchart of FIG. First, in step S51, the instantaneous power interruption flag is checked, and when the control unit 40 is normally powered on while the vehicle is stopped,
Proceeding to step S52, normal clutch control is performed. Therefore, the connection of the electromagnetic clutch 2 is controlled by executing the flowchart of FIG.

[0041] On the other hand, the power supply instantaneous and momentary power interruption occurs during travel
If the cross-sectional flag Ru Tei is set, drip coercive from step S51 to a state of forcibly clutch disengagement process proceeds to step S53. That is, the clutch current is cut off and the connection of the electromagnetic clutch 2 is prohibited.

Thereafter, the flow proceeds to step S54 to compare the target speed ratio and the actual speed ratio for the speed change control of the continuously variable transmission 4 to check for normal recovery. Here, the power supply OF of the control unit 40
In F, the continuously variable transmission 4 is in an uncontrolled state, but the actual gear ratio i becomes the intermediate gear ratio by the above-described fail-safe function of the valve characteristics, the traveling performance is secured, and the belt slip and the like are prevented. By the way, in the case of high-speed running, if the clutch is engaged even at this intermediate speed ratio, abrupt engine braking occurs. To avoid this, confirm that the actual speed ratio i has shifted to the overdrive side by restarting the speed change control function. Just connect the clutch. Therefore, if the actual speed ratio i and the target speed ratio is not the same, it is determined that the speed change control function has not returned to the normal state, the process directly exits from step S54, and the clutch connection prohibited state is maintained.

When the actual gear ratio i and the target gear ratio is coincide with each other, it is determined that the gear control function has returned to normal by turning on the power of the control unit 40 and the actual gear ratio i has converged to the target gear ratio is. The process proceeds from step S54 to step S55 to clear the power interruption flag. Thereafter, the process proceeds from step S51 to step S52, in which clutch control is performed normally, whereby the drive system returns to its original state. Therefore, the electromagnetic clutch 2 is engaged when the actual gear ratio i shifts according to the running state, thereby preventing abrupt engine braking from occurring and ensuring the safety of the occupant.

A second embodiment of the clutch connection prohibition control will be described with reference to the flowchart of FIG. This example is
The normal return of the shift control function after the power of the control unit 40 is turned on is determined based on the shift time. The time required for the actual speed ratio i to converge to the target speed ratio is changes depending on the deviation between the two, the oil temperature, the oil pump discharge amount, and the like.

Therefore, when the clutch connection is prohibited in step S63 and the process proceeds to step S64, it is checked whether or not the predetermined time has elapsed after the power is turned on. After a lapse of a predetermined time, it is determined that the actual speed ratio i has converged to the target speed ratio is, and the process proceeds to step S65 to clear the instantaneous power interruption flag. Is avoided. In this example,
Since it is not necessary to determine whether the actual speed ratio i matches the target speed ratio is, the control program is simplified and the reliability of the operation is improved.

A third embodiment of the clutch connection prohibition control will be described with reference to the flowchart of FIG. In this embodiment, when the power of the control unit 40 is turned on, the clutch connection is always prohibited depending on the time, so that it is not necessary to determine the instantaneous interruption of the power during running. Usually, it takes at least several seconds for the engine to start, select the driving range, release the parking brake, and start driving. If the running start time is longer than the maximum value of the shift time in the second embodiment, the determination of the instantaneous power interruption during running is omitted, and the power is turned on.
In this case, the clutch connection may always be prohibited for a predetermined time based on the traveling start time. Therefore, a predetermined time based on the case of normal running start is set in advance.

In this case, in step S71, the control unit 4 is turned off either when the vehicle is stopped or when the power is turned off during running.
When it is determined that the power is ON, whether or not a predetermined time has elapsed after the power is turned on is checked. If the predetermined time has not been reached, the flow advances to step S73 to forcibly prohibit the clutch connection.
Then, the normal clutch control is performed, so that the running start from the stop is performed without any trouble, and in the case of a momentary power interruption during running, sudden engine braking is avoided. In this embodiment, the control program is further simplified since there is no need to determine the instantaneous interruption of the power supply during traveling as compared with the second embodiment.

A fourth embodiment of the clutch connection prohibition control will be described with reference to the flowchart of FIG. In this embodiment, the engine brake and the shock when the clutch is engaged after the power of the control unit 40 is turned on are reduced. In order to reduce the engine brake when the clutch is engaged in accordance with the speed ratio, the speed may be controlled to be at or near the overdrive at the minimum speed ratio.

Therefore, in the case of an instantaneous power interruption during traveling, the process proceeds from step S81 to step S83 to forcibly disengage the clutch and set the target gear ratio is to overdrive.
Then, in step S84, it is checked whether or not a predetermined time has elapsed. If it is determined that the gear has shifted to overdrive or its vicinity after the lapse of the predetermined time, the process proceeds to step S85 to clear the power interruption flag. After that, step S8
The routine proceeds from step 1 to step S82, where normal clutch and shift control are performed. In the event of a momentary power interruption during running, the electromagnetic clutch 2 is connected with the continuously variable transmission 4 in the overdrive state. Here, since the moment of inertia of the engine system viewed from the driving wheels is proportional to the square of the speed ratio, for example, when the overdrive speed ratio is 0.5 with respect to the intermediate speed ratio 1.0, the engine braking force is 1 /. It becomes 4. Therefore, in this embodiment, the engine brake and the shock when the clutch is engaged are reduced, which is particularly advantageous in high-speed running.

[0050]

According to the present invention as described above,
In a vehicle in which a continuously variable transmission is connected to an engine via an automatic clutch, the automatic clutch is automatically connected / disconnected according to an electric signal of the control unit, and the speed of the continuously variable transmission is controlled. An instantaneous power interruption determining means for judging whether or not an instantaneous power interruption during traveling based on the history of the first calculation value of the power transmission, a shift control normal return determining means for judging a normal restoration of the shift control of the continuously variable transmission, In the case of an instantaneous interruption, the clutch includes a clutch connection prohibiting unit that prohibits the connection of the automatic clutch until the shift control of the continuously variable transmission returns to a normal state. Also, in this case, abrupt engine braking accompanying the connection of the automatic clutch can be avoided beforehand, and the safety of the occupant is ensured.

In the method of judging the normal return of the speed change control at the time of turning on the power while the vehicle is running on the basis of the coincidence between the target speed ratio and the actual speed ratio, the normal return of the speed change control can be confirmed. In addition, it is possible to appropriately perform traveling and shift control after the clutch is connected. The method of determining from the shift time simplifies the control program and improves the reliability of the clutch connection operation.
The method of making a determination based on the time at which the vehicle starts running after the normal engine startup eliminates the need for the instantaneous power interruption determination and further simplifies the control program. The method of setting the target gear ratio on the overdrive side can minimize engine braking and shock because the gear ratio when the clutch is engaged is small.

[Brief description of the drawings]

FIG. 1 is a claim correspondence diagram of a vehicle control device according to the present invention.

FIG. 2 is a configuration diagram illustrating an overall configuration of a vehicle control device to which the present invention is applied;

FIG. 3 is a flowchart showing clutch control.

FIG. 4 is a flowchart showing secondary pressure control of the continuously variable transmission.

FIG. 5 is a flowchart showing shift control of the continuously variable transmission.

FIG. 6 is a flowchart illustrating calculation history control.

FIG. 7 is a flowchart illustrating a momentary power interruption determination control.

FIG. 8 is a flowchart showing a first embodiment of clutch connection prohibition control.

FIG. 9 is a flowchart showing a second embodiment of the clutch connection prohibition control.

FIG. 10 is a flowchart showing a third embodiment of the clutch connection prohibition control.

FIG. 11 is a flowchart showing a fourth embodiment of the clutch connection prohibition control.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 engine 2 electromagnetic clutch (automatic clutch) 4 stepless transmission 40 control unit 41 power supply instantaneous interruption determination means 42 shift control normal return determination means 43 clutch connection prohibition means

Claims (5)

(57) [Claims] 1. A through an automatic clutch continuously variable transmission connected to the engine, a control unit for shift control of the continuously variable transmission with automatically connecting and disconnecting the clutch on the basis of various vehicle information the vehicle control device were that the control unit, based on various vehicle information at the time of power oN
And the stored history information.
A power supply interruption judging means for judging power - stop traveling based on distribution, the shift control of the continuously variable transmission is conductive on the basis of various vehicle information
A shift control normal return determining unit that determines that the vehicle has returned to a normal state after a power source instantaneous interruption; and
Disengage control of the automatic clutch and transmission control
Until your normal return judgment means judges normal return of the shift control of the continuously variable transmission coercive disconnected the automatic clutch
And a clutch connection prohibiting unit. 2. The normal-speed-recovery control means for determining a normal return when the actual speed ratio substantially matches the target speed ratio in the shift control of the continuously variable transmission.
The control device for a vehicle according to any one of the preceding claims. 3. The speed change control normal return determination means includes a predetermined time corresponding to the maximum value of a time required for the actual speed ratio to converge on the target speed ratio in the speed change control of the continuously variable transmission after the control unit is turned on. 2. The control device for a vehicle according to claim 1, wherein it is determined that the vehicle has returned to a normal state when the time has elapsed. 4. The clutch connection prohibiting means prohibits the connection of the automatic clutch at all times when the power supply of the control unit is turned on until a predetermined time based on the time from the start of the normal engine to the start of running has elapsed. The control device for a vehicle according to claim 1. 5. A shift control normal return determining means sets a target speed ratio of the continuously variable transmission at or near a minimum speed ratio, and determines that the normal speed is restored when the actual speed ratio converges to the target speed ratio. The control device for a vehicle according to claim 1, wherein the determination is performed.