JP5027772B2 - Control device for continuously variable transmission - Google Patents

Description

  The present invention relates to a control device for a continuously variable transmission, and more particularly to a control device for a belt type continuously variable transmission connected to an internal combustion engine having a valve opening / closing timing changing mechanism.

  A belt-type continuously variable transmission transmits a torque by sandwiching a metal belt from the side with a pulley. However, in order to improve torque transmission efficiency, it is necessary to apply an appropriate lateral pressure (clamping force) to the pulley. . For this purpose, it is necessary to accurately estimate the output torque of the internal combustion engine connected to the continuously variable transmission.

  By the way, there is known an internal combustion engine having a hydraulic valve opening / closing timing changing mechanism that changes the opening / closing timing of at least one of an intake valve and an exhaust valve according to an operating state. Can be mentioned.

The technique described in Patent Document 1 is configured to attenuate hydraulic oil pulsation of hydraulic oil supplied to a control valve that controls the operation of the valve opening / closing timing changing mechanism by reversing and lengthening the oil passage. is doing.
JP 2001-73725 A

  When the valve opening / closing timing is changed as in the technique described in Patent Document 1, so-called internal EGR (Exhaust Gas Recirculation) occurs in which part of the exhaust gas is returned to the intake side, thereby changing the output torque of the internal combustion engine.

  Therefore, the object of the present invention is to accurately estimate the output torque of the internal combustion engine according to the change in the opening / closing timing of the intake valve, etc., and appropriately determine the hydraulic pressure to be supplied to the continuously variable transmission to improve the torque transmission efficiency. It is an object of the present invention to provide a control device for a continuously variable transmission.

In order to achieve the above object, according to the first aspect of the present invention, the internal combustion engine is provided with a valve opening / closing timing changing mechanism that changes the opening / closing timing of at least one of the intake valve and the exhaust valve according to the operating state. In a control device for a belt type continuously variable transmission, an output torque calculating means for calculating an output torque of the internal combustion engine from a load and a rotational speed of the internal combustion engine, and a larger one of a target value and an actual value of the opening / closing timing Correction coefficient calculation means for calculating a correction coefficient from the value of the internal combustion engine and the output torque of the internal combustion engine, output torque correction means for correcting the output torque of the internal combustion engine with the calculated correction coefficient, and the corrected output torque A belt transmission torque calculating means for calculating a belt transmission torque of the continuously variable transmission based on the continuously variable transmission, and the continuously variable based on the calculated belt transmission torque. Was composed as and a transmission oil pressure supplied determining means for determining a hydraulic pressure to be supplied to speed machine.

  The control of the belt type continuously variable transmission connected to the internal combustion engine provided with the valve opening / closing timing changing mechanism for changing the opening / closing timing of at least one of the intake valve and the exhaust valve according to the operating state. In the apparatus, a first output torque calculating means for calculating a first output torque of the internal combustion engine from a load and a rotational speed of the internal combustion engine and a target value of the opening / closing timing, a load and a rotational speed of the internal combustion engine, A second output torque calculating means for calculating a second output torque of the internal combustion engine from an actual value of the opening / closing timing, and a selection for selecting a larger output torque of the first and second output torques; Means, belt transmission torque calculation means for calculating the belt transmission torque of the continuously variable transmission based on the selected output torque, and based on the calculated belt transmission torque. It was composed as and a transmission oil pressure supplied determining means for determining a hydraulic pressure to be supplied to the continuously variable transmission are.

In the control device for a continuously variable transmission according to claim 1, the output torque of the internal combustion engine is calculated from the load and the rotational speed, and the larger one of the target value and actual value of the valve opening / closing timing is determined by the internal combustion engine. The correction coefficient is calculated from the output torque of the engine, the output torque of the internal combustion engine is corrected by the calculated correction coefficient, and the belt transmission torque of the continuously variable transmission is calculated based on the corrected output torque. Thus, the output torque of the internal combustion engine can be accurately estimated even when the valve opening / closing timing is changed to change the output torque of the internal combustion engine. The hydraulic pressure to be supplied to the continuously variable transmission can be appropriately determined. Therefore, the torque transmission efficiency of the continuously variable transmission can be improved and the fuel consumption can be improved. In addition, since the hydraulic pressure to be supplied to the continuously variable transmission can be appropriately determined, it is possible to apply an appropriate lateral pressure (clamping force) to the pulley, thereby improving the durability of the belt.

  In the continuously variable transmission control device according to the second aspect, the first output torque of the internal combustion engine is calculated from the load, the rotational speed, and the target value of the switching timing, while the load, the rotational speed, and the switching timing are calculated. Calculate the second output torque of the internal combustion engine from the actual value, select the larger output torque among them, calculate the belt transmission torque of the continuously variable transmission based on the selected output torque, Since the hydraulic pressure to be supplied to the continuously variable transmission is determined based on this, similarly, when the valve opening / closing timing is changed and the output torque of the internal combustion engine changes, the output torque of the internal combustion engine can be accurately determined. The hydraulic pressure to be supplied to the continuously variable transmission can be appropriately determined. Therefore, the torque transmission efficiency of the continuously variable transmission can be improved and the fuel consumption can be improved. In addition, since the hydraulic pressure to be supplied to the continuously variable transmission can be appropriately determined, it is possible to apply an appropriate lateral pressure (clamping force) to the pulley, thereby improving the durability of the belt.

  The best mode for carrying out a continuously variable transmission control apparatus according to the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a schematic diagram generally showing a continuously variable transmission control apparatus according to a first embodiment of the present invention.

  In FIG. 1, reference numeral 10 indicates an internal combustion engine (hereinafter referred to as “engine”). The engine 10 is mounted on a vehicle (partially indicated by drive wheels W or the like) 12.

  In the engine 10, a throttle valve (not shown) arranged in the intake system is mechanically disconnected from an accelerator pedal (not shown) arranged in the driver's seat of the vehicle 12, and an actuator (such as an electric motor) It is connected to and driven by a DBW (Drive By Wire) mechanism 14 comprising a not-shown).

  The intake air metered by the throttle valve flows through an intake manifold (not shown) and mixes with fuel injected from an injector (fuel injection valve) 16 near the intake port of each cylinder to form an air-fuel mixture, When an intake valve (not shown) is opened, it flows into a combustion chamber (not shown) of the cylinder. In the combustion chamber, the air-fuel mixture is ignited and combusted, and after driving a piston (not shown) to rotate a crankshaft (not shown), it becomes exhaust and an exhaust valve (not shown) is opened. Sometimes it is released outside the engine 10.

  The crankshaft of the engine 10 is fixed to the drive plate 20. The drive plate 20 is connected to a pump / impeller 22a of a torque converter 22 that also serves as a flywheel mass, and a turbine runner 22b that is disposed opposite to the drive plate 20 and receives fluid (hydraulic fluid) is connected to a main shaft (mission input shaft) MS. Connected. Reference numeral 22c denotes a lockup clutch.

  A continuously variable transmission (hereinafter referred to as “CVT”) 26 is connected downstream of the torque converter 22 via a forward / reverse switching mechanism 24.

  The CVT 26 includes a drive pulley 26a disposed on the main shaft MS, a driven pulley 26b disposed on a counter shaft CS parallel to the main shaft MS, and a metal belt 26c wound around the drive pulley 26a.

  The drive pulley 26a includes a fixed pulley half 26a1 disposed on the main shaft MS and a movable pulley half 26a2 that can move relative to the fixed pulley half 26a1 in the axial direction. The driven pulley 26b includes a fixed pulley half 26b1 fixed to the countershaft CS and a movable pulley half 26b2 that can move relative to the fixed pulley half 26b1 in the axial direction.

  The belt 26c is composed of two bundles of rings and a large number of, for example, about 400 elements (shown later in FIG. 5) held by the rings, and the elements are sequentially pushed to move the drive pulley 26a to the driven pulley 26b. Torque is transmitted.

  The forward / reverse switching mechanism 24 includes a ring gear 24a fixed to the main shaft MS, a sun gear 24b fixed to the fixed pulley half 26a1 of the drive pulley 26a of the CVT 26, a pinion gear carrier 24c disposed therebetween, and a ring gear 24a A forward clutch 24d capable of fastening the sun gear 24b and a reverse brake clutch 24e capable of fixing the pinion gear carrier 24c to a transmission case (not shown).

  A secondary drive gear 30 is fixed to the counter shaft CS, and the secondary drive gear 30 meshes with a secondary driven gear 32 fixed to the secondary shaft SS. A final drive gear 34 is fixed to the secondary shaft SS, and the final drive gear 34 meshes with a final driven gear 36 of the differential mechanism D.

  With the above configuration, the rotation of the counter shaft CS is transmitted to the secondary shaft SS through the gears 30 and 32, and the rotation of the secondary shaft SS is transmitted to the differential D through the gears 34 and 36, and is distributed there. It is transmitted to the drive wheel (tire, only shown on the right side) W. A disc brake 40 is disposed in the vicinity of the drive wheel W.

  FIG. 2 is a hydraulic circuit diagram schematically showing a hydraulic mechanism such as the CVT 26.

  As illustrated, a hydraulic pump 42a is provided in the hydraulic mechanism (indicated by reference numeral 42). The hydraulic pump 42a is composed of a vane pump, is driven by the engine 10, pumps up the hydraulic oil stored in the reservoir 42b, and pumps it to a PH control valve (PH REG VLV) 42c.

  The output (PH pressure (line pressure)) of the PH control valve 42c, on the other hand, is driven from the oil passage 42d through the first and second regulator valves (DR REG VLV, DN REG VLV) 42e, 42f, and the drive pulley 26a of the CVT 26. Are connected to the piston chamber (DR) 26a21 of the movable pulley half 26a2 and the piston chamber (DN) 26b21 of the movable pulley half 26b2 of the driven pulley 26b, and on the other hand, the CR valve (CR VLV) via the oil passage 42g. 42h.

  The CR valve 42h reduces the PH pressure to generate a CR pressure (control pressure), and the first, second, and third (electromagnetic) linear solenoid valves 42j, 42k, 42l (LS-DR, LS) from the oil passage 42i. -DN, LS-CPC). The first and second linear solenoid valves 42j and 42k act on the first and second regulator valves 42e and 42f with the output pressure determined according to the excitation of the solenoids, and the PH pressure sent from the oil passage 42d. Hydraulic oil is supplied to the piston chambers 26a21 and 26b21 of the movable pulley halves 26a2 and 26b2, and a pulley side pressure is generated accordingly.

  Therefore, in the configuration shown in FIG. 1, the pulley side pressure that moves the movable pulley halves 26a2 and 26b2 in the axial direction is generated, the pulley widths of the drive pulley 26a and the driven pulley 26b change, and the winding radius of the belt 26c changes. Changes. Thus, by adjusting the side pressure of the pulley, the transmission gear ratio for transmitting the output of the engine 10 to the drive wheels W can be changed steplessly.

  The output (CR pressure) of the CR valve 42h is also connected to a CR shift valve (CR SFT VLV) 42n, and from there through a manual valve (MAN VLV) 42o, the piston chamber (FWD) of the forward clutch 24d of the forward / reverse switching mechanism 24 ) 24d1 and the piston chamber (RVS) 24e1 of the reverse brake clutch 24e.

  The operation of the forward clutch 24d and the reverse brake clutch 24e is performed by the driver operating a select lever 44 provided in the driver's seat of the vehicle 12, for example, having a range (position) of P, R, N, D, S, and L. To be determined. That is, when one of the ranges of the select lever 44 is selected by the driver, the selection operation is transmitted to the manual valve 42o of the hydraulic mechanism 42.

  For example, when the D, S, L range, that is, the forward travel range is selected, the spool of the manual valve 42o moves accordingly, and hydraulic oil (hydraulic pressure) is discharged from the piston chamber 24e1 of the reverse brake clutch 24e. The hydraulic fluid is supplied to the piston chamber 24d1 of the forward clutch 24d, and the forward clutch 24d is fastened. When the forward clutch 24d is engaged, all the gears rotate together with the main shaft MS, and the drive pulley 26a is driven in the same direction as the main shaft MS (a direction corresponding to the direction in which the vehicle 12 moves forward).

  On the other hand, when the R range (reverse travel range) is selected, the hydraulic oil is discharged from the piston chamber 24d1 of the forward clutch 24d, while the hydraulic oil is supplied and fastened to the piston chamber 24e1 of the reverse brake clutch 24e. As a result, the pinion gear carrier 24c is fixed to the transmission case, the sun gear 24b is driven in the opposite direction to the ring gear 24a, and the drive pulley 26a is driven in the opposite direction to the main shaft MS (corresponding to the direction in which the vehicle 12 moves backward). Is done.

  When the P or N range is selected, the hydraulic oil is discharged from both piston chambers, the forward clutch 24d and the reverse brake clutch 24e are both released, and the power transmission via the forward / reverse switching mechanism 24 is cut off. The power transmission between the engine 10 and the drive pulley 26a of the CVT 26 is cut off.

  The output of the PH control valve 42c is sent to the TC regulator valve (TC REG VLV) 42q through the oil passage 42p, and the output of the TC regulator valve 42q is LC shifted through the LC control valve (LC CTL VLV) 42r. Connected to valve (LC SFT VLV) 42s. The output of the LC shift valve 42s is connected to the piston chamber 22c1 of the lockup clutch 22c of the torque converter 22 on the one hand and to the chamber 22c2 on the back side on the other hand.

  The CR shift valve 42n and the LC shift valve 42s are connected to first and second (electromagnetic) on / off solenoids (SOL-A, SOL-B) 42u and 42v, and the oil to the forward clutch 24d is excited or de-energized. The switching of the road and the engagement (on) / release (off) of the lock-up clutch 22c are controlled.

  In the lockup clutch 22c, the hydraulic oil is supplied to the piston chamber 22c1 via the LC shift valve 42s, while the lockup clutch 22c is engaged (fastened on) when discharged from the chamber 22c2 on the back side. ) And supplied to the back side chamber 22c2 and released (not fastened, off) when discharged from the piston chamber 22c1. The slip amount of the lock-up clutch 22c, that is, the engagement capacity when the lock-up clutch 22c is slipped between engagement and release is determined by the amount of hydraulic oil (hydraulic pressure) supplied to the piston chamber 22c1 and the rear chamber 22c2. The

  The previously described third linear solenoid valve 42l is connected to the LC shift valve 42s via the oil passage 42w and the LC control valve 42r, and further connected to the CR shift valve 42n via the oil passage 42x. That is, the engagement capacity (slip amount) of the forward clutch 24d and the lockup clutch 22c is adjusted (controlled) by the excitation / non-excitation of the solenoid of the third linear solenoid valve 42l.

  Returning to the description of FIG. 1, a TDC sensor 50 is provided near the camshaft of the engine 10 to output a signal indicating the TDC position of the piston, and a crank angle sensor 51 is provided near the crankshaft. A pulse signal indicating a predetermined crank angle position of the piston is output. An intake pressure sensor 52 is provided at an appropriate position downstream of the throttle valve in the intake system, and outputs a signal proportional to the intake pressure (engine load) PBA.

  The actuator of the DBW mechanism 14 is provided with a throttle opening sensor 54 that outputs a signal proportional to the throttle opening TH through the amount of rotation of the actuator, and an accelerator opening sensor 56 is provided near the accelerator pedal. A signal proportional to the accelerator opening AP corresponding to the accelerator pedal operation amount is output.

  Further, an atmospheric pressure sensor 58 is provided at an appropriate position of the engine 10 to generate an output indicating the atmospheric pressure of the ground where the vehicle 12 (and the engine 10) is located. Further, a water temperature sensor 60 is provided in the vicinity of a cooling water passage (not shown) to generate an output corresponding to the engine cooling water temperature TW, in other words, the temperature of the engine 10, and an intake air temperature sensor 62 is provided in the intake system. An output corresponding to the intake air temperature (outside air temperature) taken into the engine 10 is generated.

  The sensor output described above is sent to the engine controller 64. The engine controller 64 includes a microcomputer including a CPU, ROM, RAM, I / O, and a waveform shaping circuit. The engine controller 64 measures the output pulse interval time of the crank angle sensor 51 to detect the engine speed NE, and determines a target throttle opening based on the detected engine speed NE and other sensor outputs. Then, the operation of the DBW mechanism 14 is controlled, the fuel injection amount is determined, and the injector 16 is driven.

  An NT sensor (rotational speed sensor) 66 is provided at an appropriate position in the vicinity of the main shaft MS, and outputs a pulse signal indicating the rotational speed of the main shaft MS corresponding to the rotational speed of the turbine runner 22b. An NDR sensor (rotation speed sensor) 70 is provided at an appropriate position near the drive pulley 26a to output a pulse signal indicating the rotation speed of the drive pulley 26a.

  A VEL sensor (rotational speed sensor) 72 is provided in the vicinity of the secondary driven gear 32 of the secondary shaft SS, and outputs a pulse signal indicating the output rotational speed of the CVT 26 or the vehicle speed VEL through the rotational speed of the secondary driven gear 32. A select lever sensor 74 is provided in the vicinity of the select lever 44 described above, and outputs a signal corresponding to a range such as R, N, and D selected by the driver.

  In the hydraulic mechanism 42, an oil temperature sensor 76 is disposed in the reservoir 42b to generate an output corresponding to the temperature of the hydraulic oil (oil temperature), and is connected to the piston chamber 26b21 of the movable pulley half 26b2 of the driven pulley 26b. A hydraulic pressure sensor 78 is disposed in the oil path to generate an output corresponding to the pressure (hydraulic pressure) of the hydraulic oil supplied to the piston chamber 26b21.

  The output from the NT sensor 66 and the like described above is sent to the shift controller 80. Similarly to the engine controller 64, the shift controller 80 includes a microcomputer including a CPU, ROM, RAM, I / O, a waveform shaping circuit, and the like, and is configured to be communicable with the engine controller 64. The shift controller 80 includes a nonvolatile memory 80a.

  In the shift controller 80, the outputs of the NT sensor 66 and the NDR sensor 70 are input to the waveform shaping circuit, and the CPU detects the rotation speed from the outputs. The output of the VEL sensor 72 is input to the direction detection circuit after being input to the waveform shaping circuit. The CPU counts the output of the waveform shaping circuit to detect the output rotation speed (and the vehicle speed) of the CVT 26 and detects the rotation direction of the CVT 26 from the output of the direction detection circuit.

  Based on these detected values, the shift controller 80 determines the supply hydraulic pressure of the CVT 26 and controls the operation of the CVT 26 by exciting / de-exciting the electromagnetic solenoid valve 42j of the hydraulic mechanism 42 and the lock-up clutch 22c of the torque converter 22. And the engagement / release of the forward clutch 24d and the reverse brake clutch 24e.

  In addition to the above-described configuration, a change mechanism 84 that changes the valve opening / closing timing is provided near the intake camshaft of the engine 10.

  The engine 10 has two intake and exhaust camshafts arranged on the upper part of the crankshaft, and is driven by a chain by the crankshaft to make one revolution per two revolutions of the crankshaft.

  The change mechanism 84 includes a vane portion connected to the intake camshaft, an actuator 84a including a timing gear, a hydraulic valve 84b (both shown in FIG. 4), and the like, and supplies hydraulic oil to the left and right oil chambers of the vane portion. The vane portion is rotated with respect to the timing gear, and the angle (phase) of the intake camshaft connected to the vane portion is rotated in the advance direction with respect to the crankshaft, thereby at least one of the intake valve and the exhaust valve, Specifically, the opening / closing timing of the intake valve is changed.

  FIG. 3 is an explanatory diagram showing the opening / closing timing of the intake and exhaust valves by the change mechanism 84 with respect to the crank angle.

  In FIG. 3, the characteristic IN1 is the angle of the intake camshaft, that is, when the operating angle of the actuator 84a of the changing mechanism 84 is not changed (initial), and the characteristic IN2 is the intake valve when the operating angle is changed to the maximum. Indicates the opening and closing timing.

  The operating angle of the change mechanism 84, that is, the opening / closing timing of the intake valve can be continuously changed in the traveling direction at the crank angle between the characteristics IN1 and IN2, and therefore the overlap amount with the opening / closing timing of the exhaust valve is also characteristic IN1. Can be continuously changed between a at the time of b and b at the characteristic IN2. This operating angle is a value indicating a displacement angle from when the state (initial state) in which the changing mechanism 84 is not operated is zero.

  FIG. 4 is a block diagram for explaining the control of the changing mechanism 84 performed by the engine controller 64 described above.

  The engine controller 64 is a target value of the operating angle of the actuator 84a of the change mechanism 84 according to the operating state determined from the outputs of the crank angle sensor 51, the intake pressure sensor 52, the throttle opening sensor 54, and the atmospheric pressure sensor 58. A target operating angle (the target angle of the intake camshaft, that is, the opening / closing timing of the intake valve, more precisely, the target value of the opening timing) is calculated.

  The engine controller 64 includes a cam sensor 68 that generates an output corresponding to the rotational speed of the intake camshaft, and is an actual value of the operating angle of the actuator 84a of the changing mechanism 84 from the outputs of the cam sensor 68, the TDC sensor 50, and the crank angle sensor 51. The actual operating angle (actual angle of the intake camshaft, that is, the opening / closing timing of the intake valve, more precisely the actual value of the opening timing) is calculated (detected).

  Next, the engine controller 64 obtains the deviation between the calculated target operating angle and the actual operating angle, and adjusts the opening of the hydraulic valve 84b by calculating and driving the drive duty of the electromagnetic solenoid valve of the hydraulic valve 84b accordingly. Then, the supply and discharge of the hydraulic oil to and from the oil chamber of the vane portion is controlled so that the actual operating angle of the actuator 84a of the change mechanism 84 becomes the target operating angle. Further, the engine controller 64 determines whether the operation of the changing mechanism 84 is permitted from the outputs of the crank angle sensor 51, the water temperature sensor 60, and the intake air temperature sensor 62.

  Although explanation is omitted, in addition to the valve opening / closing timing changing mechanism 84, a valve lift amount changing mechanism is also provided, and the shift controller 80 also changes the lift amount itself of the intake and exhaust valves. The description is omitted here.

  FIG. 5 is a flowchart showing the control operation of the CVT 26 of the shift controller 80. The illustrated program is executed by the shift controller 80 every predetermined time, for example, every 10 msec.

  In the following, torque output from the engine 10 is calculated from the load and the rotational speed of the engine 10 in S10. This is done by searching a map showing the characteristics in FIG. 6 from the detected engine speed NE and intake pressure PBA (indicating load). Since the intake pressure PBA is set only at some representative points, the engine torque when the intake pressure is other than the set value is obtained by interpolation.

  Next, in S12, the torque output by the engine 10 according to the target operating angle (of the actuator 84a of the changing mechanism 84), that is, the torque output by the engine 10 according to the target value of the opening / closing timing of the intake valve is calculated.

  This is calculated by searching a map showing the characteristics in FIG. 7 from the target operating angle, the detected engine speed NE and the intake pressure PBA. As shown in FIG. 7, maps are prepared for each of four types of operating angles A, B, C, and D, and the intake pressure PBA is also set at several representative points, so the operating angle and intake pressure are set. The output torque at a value other than the value is obtained by interpolation.

  Next, in S14, the torque output by the engine 10 according to the actual operating angle (of the actuator 84a of the changing mechanism 84), that is, the torque output by the engine 10 according to the actual value of the opening / closing timing of the intake valve is calculated.

  This is also calculated by searching a map showing the characteristics in FIG. 7 from the actual operating angle, the detected engine speed NE and the intake pressure PBA. Similarly, the output torque when the operating angle and the intake pressure are other than the set values is obtained by interpolation.

  Next, in S16, it is determined whether or not the engine torque corresponding to the target operating angle is larger than the engine torque corresponding to the actual operating angle. If the result is affirmative, the process proceeds to S18, and the target operation is performed with the engine torque calculated in S10. The quotient obtained by dividing the engine torque according to the angle is used as the correction coefficient.

  On the other hand, when the result in S16 is negative, the program proceeds to S20, and the quotient obtained by dividing the engine torque corresponding to the actual operating angle by the engine torque calculated in S10 is used as the correction coefficient. The processing from S12 to S20 corresponds to calculating a correction coefficient from the target value and actual value of the intake valve opening and closing timing.

  Next, the process proceeds to S22, in which the pulley torque calculation torque (corrected output torque) is calculated by multiplying the engine torque calculated in S10 by the correction coefficient calculated in S18 (or S20).

  FIG. 8 is a graph showing the relationship between the operating angle, engine torque, and belt transmission torque.

  The above will be described with reference to FIG. 8. As shown in FIGS. 8A and 8B, the engine torque decreases because the internal EGR amount increases as the operating angle is advanced. The engine torque was corrected accordingly, and the larger of the target operating angle and the actual operating angle was used for the correction. This is because the belt 26c may slip if the lateral pressure is determined by estimating it lower than the actual input torque of the CVT 26 in the transition of the operating angle.

  However, when the target operating angle (or actual operating angle) increases rapidly as shown in FIG. 10A, the pulley clamping force calculation torque is corrected as shown in FIGS. Decrease gently. This is intended to suppress slippage of the belt 26c due to an undershoot of the hydraulic pressure supplied to the CVT 26.

  FIG. 9 is a flowchart showing a pulley side pressure determination process performed based on the pulley clamping force calculation torque calculated in the process of FIG. This process is also executed by the shift controller 80 every predetermined time, for example, every 10 msec.

  As will be described below, in S100, another correction coefficient, for example, an environmental correction coefficient corresponding to the intake air temperature TA detected by the intake air temperature sensor 62 is calculated, and a correction coefficient corresponding to the retard amount of the ignition timing is calculated.

  Since the torque output from the engine 10 decreases as the intake air temperature TA increases, the environmental correction coefficient is set to decrease as the intake air temperature TA increases.

  Next, in S102, the pulley clamping force calculation torque is corrected again by multiplying the correction coefficient calculated in S100.

  Next, in S104, based on the calculated (corrected) pulley clamping force calculation torque, more precisely, the calculated torque ratio of the torque converter 22 to the pulley clamping force calculation torque (the detected engine speed NE and the main torque is calculated). The belt transmission torque of the CVT 26 is calculated so as to be able to transmit the product obtained by multiplying the map MS from the rotation speed of the shaft MS.

  Next, the process proceeds to S106, and based on the calculated belt transmission torque, more precisely, based on the calculated belt transmission torque, the engine speed NE detected from the detected vehicle speed and throttle opening becomes the target value. Then, the shift map is searched to determine the hydraulic pressure (side pressure) to be supplied to the drive pulley 26a and the driven pulley 26b. That is, the hydraulic pressure (side pressure) to be supplied to the CVT 26 is determined based on the calculated belt transmission torque.

  FIG. 10 is a data diagram showing the simulation results of the first embodiment.

  As shown in the figure, it can be seen that the correction coefficient is properly calculated according to the torque calculated from the operating angle.

As described above, the first embodiment is connected to the engine (internal combustion engine) 10 including the valve opening / closing timing changing mechanism 84 that changes the opening / closing timing of at least one of the intake valve and the exhaust valve according to the operating state. Output for calculating the engine output torque from the engine load (intake pressure PBA) and the rotational speed (engine rotational speed) NE in the control device (shift controller 80) of the belt type CVT (continuously variable transmission) 26 Correction coefficient calculation for calculating a correction coefficient from the torque calculation means (S10), the larger value of the target value (target operating angle) and the actual value (actual operating angle) of the opening / closing timing, and the output torque of the engine Means (S12 to S20), output torque correction means (S22) for correcting the output torque of the engine with the calculated correction coefficient, Belt transmission torque calculation means (S100 to S104) for calculating the belt transmission torque of the CVT based on the corrected output torque, and hydraulic pressure (side pressure) to be supplied to the CVT 26 based on the calculated belt transmission torque The transmission supply hydraulic pressure determining means (S106) for determining the engine output torque is determined so that the output torque of the engine can be accurately estimated even when the valve opening / closing timing is changed and the output torque of the engine 10 changes. The hydraulic pressure to be supplied to the CVT 26 can be appropriately determined. Therefore, the torque transmission efficiency of the CVT 26 can be improved, and the fuel consumption can be improved. In addition, since the hydraulic pressure to be supplied to the CVT 26 can be appropriately determined, it is possible to apply an appropriate lateral pressure (clamping force) to the drive pulley 26a and the driven pulley 26b, thereby improving the durability of the belt 26c.

  FIG. 11 is a flow chart similar to FIG. 5 showing the operation of the control device for the continuously variable transmission according to the second embodiment of the present invention.

  Explained below, in S200, as in the first embodiment, a map similar to the map shown in FIG. 7 is searched to calculate the torque (first output torque) output by the engine 10 in accordance with the target operating angle, and then Proceeding to S202, a torque (second output torque) output from the engine 10 is calculated according to the actual operating angle.

  Next, in S204, it is determined whether or not the engine torque corresponding to the target operating angle is larger than the engine torque corresponding to the actual operating angle. If the determination is affirmative, the process proceeds to S206 and the engine torque corresponding to the target operating angle is set to the pulley. On the other hand, if the determination is negative, the process proceeds to S208, and the engine torque corresponding to the actual operating angle is determined as the pulley clamping force calculation torque.

  Next, the belt transmission torque is calculated based on the pulley clamping force calculation torque calculated according to the processing similar to the processing shown in the flowchart of FIG. 9, and the pulley side pressure is determined based on the belt transmission torque. The remaining configuration is not different from the first embodiment.

  As described above, the second embodiment is connected to the engine (internal combustion engine) 10 including the valve opening / closing timing changing mechanism 84 that changes the opening / closing timing of at least one of the intake valve and the exhaust valve according to the operating state. In the control device (shift controller 80) of the belt type CVT (continuously variable transmission) 26, the engine load (intake pressure PBA), the rotational speed (engine rotational speed NE), and the target value of the opening / closing timing (target operation) First output torque calculating means (S200) for calculating the first output torque of the engine 10 from the angle, the load (intake pressure PBA), the rotational speed (engine rotational speed NE) of the engine 10 and the opening / closing. Second output torque calculating means (S202) for calculating a second output torque of the engine 10 from an actual timing value (actual operating angle); Selection means (S204 to S208) for selecting the larger output torque of the first and second output torques, and a belt transmission torque for calculating the belt transmission torque of the CVT 26 based on the selected output torque Calculation means (processing similar to S100 to S104) and transmission supply hydraulic pressure determination means (processing similar to S106) for determining the hydraulic pressure to be supplied to the CVT 26 based on the calculated belt transmission torque. As in the first embodiment, even when the valve opening / closing timing is changed and the output torque of the engine 10 changes, the output torque of the engine 10 can be accurately estimated and supplied to the CVT 26. Hydraulic pressure can be determined properly. Therefore, the torque transmission efficiency of the CVT 26 can be improved, and the fuel consumption can be improved. In addition, since the hydraulic pressure to be supplied to the CVT 26 can be appropriately determined, it is possible to apply an appropriate lateral pressure (clamping force) to the pulleys 26a and 26b, thereby improving the durability of the belt 26c.

  FIG. 12 is a flow chart similar to FIG. 5 showing the operation of the continuously variable transmission control apparatus according to the third embodiment of the present invention.

  Explained below, in S300, as in the first embodiment, a map similar to the map shown in FIG. 6 is searched, and the torque output by the engine 10 is calculated.

  Next, the routine proceeds to S302, where the exhaust gas recirculation rate returned to the intake side to the engine 10 according to the operating angle (of the actuator 84a of the changing mechanism 84) is calculated according to the characteristics shown in FIG. The actual operating angle is used as the operating angle.

  Next, in S304, a correction coefficient is calculated from the calculated recirculation rate according to the characteristics shown in FIG. 14, and in S306, the engine torque calculated in S300 is multiplied by the correction coefficient calculated in S304. Torque (corrected output torque) is calculated.

  Next, the belt transmission torque is calculated based on the pulley clamping force calculation torque calculated according to the processing similar to the processing shown in the flowchart of FIG. 9, and the pulley side pressure is determined based on the belt transmission torque. The remaining configuration is not different from the first embodiment.

  As described above, the third embodiment is connected to the engine (internal combustion engine) 10 including the valve opening / closing timing changing mechanism 84 that changes the opening / closing timing of at least one of the intake valve and the exhaust valve according to the operating state. The output torque of the engine 10 is calculated from the load (intake pressure PBA) and the rotational speed (engine speed) NE of the engine 10 in the control device (shift controller 80) of the belt-type CVT (continuous transmission) 26. Output torque calculating means (S300), a recirculation rate calculating means (S302) for calculating a recirculation rate of exhaust gas according to the opening / closing timing (operating angle (of the actuator 84a of the changing mechanism 84)), and the calculated recirculation rate Correction coefficient calculating means (S304) for calculating a correction coefficient from the rate, and the calculated correction of the output torque of the engine 10 Output torque correction means (S306) for correcting by a number, belt transmission torque calculation means for calculating the belt transmission torque of the CVT 26 based on the corrected output torque (the same processing as S100 to S104), and the calculation. Since the transmission supply hydraulic pressure determining means (the same processing as S106) for determining the hydraulic pressure to be supplied to the CVT 26 based on the belt transmission torque is provided, similarly, the valve opening / closing timing is changed and the engine is changed. Even when the output torque of the engine 10 changes, the output torque of the engine 10 can be accurately estimated, and the hydraulic pressure to be supplied to the CVT 26 can be determined appropriately. Therefore, the torque transmission efficiency of the CVT 26 can be improved, and the fuel consumption can be improved. In addition, since the hydraulic pressure to be supplied to the CVT 26 can be appropriately determined, it is possible to apply an appropriate lateral pressure (clamping force) to the pulleys 26a and 26b, thereby improving the durability of the belt 26c.

  In addition, in the above, the structure of CVT26 or the forward / reverse switching mechanism 24 is an illustration, and this invention is not limited to it.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram showing an overall control device for a continuously variable transmission according to a first embodiment of the present invention. FIG. 2 is a hydraulic circuit diagram schematically showing a hydraulic mechanism such as a CVT (transmission) shown in FIG. 1. It is explanatory drawing which shows the opening / closing timing of the suction and exhaust valves by the valve opening / closing timing changing mechanism shown in FIG. 1 with respect to the crank angle. It is a block diagram explaining the control of the valve opening / closing timing changing mechanism performed by the engine controller shown in FIG. It is a flowchart which shows operation | movement of the apparatus shown in FIG. It is explanatory drawing which shows the characteristic of the map used by the process of FIG. Similarly, it is explanatory drawing which shows the characteristic of the map used by the process of FIG. 2 is a graph showing the relationship between the operating angle, engine torque, and belt transmission torque of the valve opening / closing timing changing mechanism of FIG. 1. 6 is a flowchart showing a pulley side pressure determination process performed based on the pulley clamp force calculation torque calculated in the process of FIG. 5. It is a data figure which shows the simulation result of 1st Example. FIG. 6 is a flowchart similar to FIG. 5 showing the operation of the control device for the continuously variable transmission according to the second embodiment of the present invention. FIG. 9 is a flow chart similar to FIG. 5 showing the operation of the continuously variable transmission control apparatus according to the third embodiment of the present invention. FIG. It is explanatory drawing which shows the characteristic of the reflux rate calculated by the process of FIG. Similarly, it is explanatory drawing which shows the characteristic of the correction | amendment reflux rate calculated by the process of FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Internal combustion engine (engine), 12 Vehicle, 22 Torque converter, 24 Forward / reverse switching mechanism, 24a Ring gear, 24b Sun gear, 24c Pinion gear carrier, 24d Forward clutch, 24e Reverse brake clutch, 26 Continuously variable transmission (CVT), 26a Drive Pulley, 26b Driven pulley, 26c Belt, 26c1 element, 42 Hydraulic mechanism, 44 Select lever, 51 Crank angle sensor, 52 Intake pressure sensor, 60 Water temperature sensor, 62 Intake temperature sensor, 64 Engine controller, 66 NT sensor, 70 NDR sensor , 72 VEL sensor, 80 shift controller, 84 valve opening / closing timing change mechanism, 84a actuator, MS main shaft, CS counter shaft, SS secondary shaft D differential, W drive wheel (tire)

Claims (2)

In a control device for a belt-type continuously variable transmission connected to an internal combustion engine having a valve opening / closing timing changing mechanism that changes the opening / closing timing of at least one of an intake valve and an exhaust valve according to an operating state,
a. Output torque calculating means for calculating the output torque of the internal combustion engine from the load and rotation speed of the internal combustion engine;
b. Correction coefficient calculation means for calculating a correction coefficient from the larger one of the target value and actual value of the opening / closing timing and the output torque of the internal combustion engine ;
c. Output torque correction means for correcting the output torque of the internal combustion engine with the calculated correction coefficient;
d. Belt transmission torque calculating means for calculating a belt transmission torque of the continuously variable transmission based on the corrected output torque;
e. A transmission supply hydraulic pressure determination means for determining a hydraulic pressure to be supplied to the continuously variable transmission based on the calculated belt transmission torque;
A control device for a continuously variable transmission. In a control device for a belt-type continuously variable transmission connected to an internal combustion engine having a valve opening / closing timing changing mechanism that changes the opening / closing timing of at least one of an intake valve and an exhaust valve according to an operating state,
a. First output torque calculating means for calculating a first output torque of the internal combustion engine from a load and rotation speed of the internal combustion engine and a target value of the opening / closing timing;
b. Second output torque calculating means for calculating the second output torque of the internal combustion engine from the load and rotation speed of the internal combustion engine and the actual value of the opening / closing timing;
c. Selecting means for selecting the larger output torque of the first and second output torques;
d. Belt transmission torque calculating means for calculating a belt transmission torque of the continuously variable transmission based on the selected output torque;
e. A transmission supply hydraulic pressure determination means for determining a hydraulic pressure to be supplied to the continuously variable transmission based on the calculated belt transmission torque;
A control device for a continuously variable transmission.

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