JP2013152008A - Control device of belt type continuously variable transmission - Google Patents

Abstract

To provide a control device for a belt-type continuously variable transmission capable of improving the shift following ability.
An ECU that controls a belt-type continuously variable transmission mechanism corrects a thrust ratio map in accordance with at least one of a vehicle speed or an oil temperature of oil supplied to the belt-type continuously variable transmission mechanism, and corrects thrust. The ratio map is used to determine the thrust ratio. Further, the correction of the thrust ratio map according to the vehicle speed is performed based on the vehicle speed corresponding thrust ratio correction map in which the relationship among the transmission ratio, the thrust ratio, and the vehicle speed is predetermined. Further, the correction of the thrust ratio map according to the oil temperature is performed based on the oil temperature corresponding thrust ratio correction map in which the relationship among the transmission ratio, the thrust ratio, and the oil temperature is determined in advance.
[Selection] Figure 2

Description

  The present invention relates to a control device for a belt-type continuously variable transmission, and more particularly to a control device for a belt-type continuously variable transmission that continuously changes a gear ratio by controlling a thrust ratio between a primary pulley and a secondary pulley.

  Conventionally, as a control device for a belt type continuously variable transmission, a target speed ratio ip is calculated based on vehicle information, a thrust ratio RF for maintaining the target speed ratio ip is calculated, and a drive side slip where the belt does not slip is calculated. When the lower limit value Flp and the driven side slip lower limit value Fls are calculated and the thrust ratio RF is less than 1, the drive side slip lower limit value Flp is set as the target hydraulic thrust of the drive pulley, and the drive side slip lower limit value Flp The target hydraulic thrust Fls + ΔFp of the driven pulley is calculated based on the target speed ratio ip, and when the thrust ratio RF is 1 or more, the driven slip lower limit is set to the target hydraulic thrust of the driven pulley, and the driven side A configuration is known in which a target hydraulic thrust force Flp + ΔFs of a driving pulley is calculated based on a slip lower limit value Fls and a target speed ratio ip (see, for example, Patent Document 1).

  That is, in the control device for the belt-type continuously variable transmission described in Patent Document 1, in order to realize the target gear ratio, a primary pulley is used by using a thrust ratio that is a ratio of two pulley thrusts of the belt-type continuously variable transmission. And the oil pressure of the secondary pulley is determined. Further, since the thrust ratio for realizing the target gear ratio changes according to the vehicle state, the thrust ratio is corrected according to the input torque.

JP 2007-132419 A

  However, in such a conventional belt type continuously variable transmission control device, the thrust ratio is corrected according to the input torque, but the thrust ratio correction considering the vehicle state other than the input torque is not possible. not going. For this reason, when the vehicle state other than the input torque changes, the thrust ratio changes due to the deformation of the pulley or the friction coefficient between the belt and the pulley, and the actual thrust ratio deviates from the target thrust ratio. There was a problem that the shift-following performance to the vehicle was not good.

  The present invention has been made to solve the conventional problems as described above, and an object of the present invention is to provide a control device for a belt-type continuously variable transmission that can improve the shift following ability.

  In order to achieve the above object, a control device for a belt-type continuously variable transmission according to the present invention (1) based on a thrust ratio map in which a relationship between a gear ratio and a thrust ratio is determined in advance, A control device for a belt-type continuously variable transmission that continuously changes the gear ratio by controlling a thrust ratio according to at least one of a vehicle speed or an oil temperature of oil supplied to the belt-type continuously variable transmission. The thrust ratio map is corrected.

  With this configuration, the thrust ratio map is determined based on the corrected thrust ratio map by correcting the thrust ratio map according to at least one of the vehicle speed and the oil temperature, so that the actual thrust ratio is close to the target thrust. And the actual gear ratio is close to the target gear ratio. Therefore, the shift following ability can be improved.

  In order to achieve the above object, the control device for a belt-type continuously variable transmission according to the present invention has previously determined the relationship among (2) the gear ratio, the thrust ratio, and the vehicle speed in (1) above. Based on a vehicle speed corresponding thrust ratio correction map, the thrust ratio map is corrected according to the vehicle speed.

  With this configuration, the thrust ratio is determined by a thrust ratio map that takes into account the vehicle speed that affects the friction coefficient between the belt and pulley, etc., so that the actual thrust ratio is close to the target thrust and the actual speed ratio. Becomes close to the target gear ratio, and the shift tracking performance can be improved.

  In order to achieve the above object, the control device for a belt-type continuously variable transmission according to the present invention is configured in (1) above, wherein (3) the relationship among the transmission ratio, the thrust ratio, and the oil temperature is determined in advance. The thrust ratio map is corrected based on the oil temperature based on the oil temperature corresponding thrust ratio correction map.

  With this configuration, the thrust ratio is determined by a thrust ratio map that takes into account the oil temperature that affects the friction coefficient between the belt and pulley, etc., so that the actual thrust ratio becomes close to the target thrust and the actual speed change. The ratio becomes close to the target gear ratio, and the shift tracking performance can be improved.

It is a block diagram which shows the structure of the control apparatus of the belt-type continuously variable transmission which concerns on this invention. It is a functional block diagram of the control apparatus of the belt type continuously variable transmission according to the present invention. It is a figure which shows the thrust ratio map of the control apparatus of the belt-type continuously variable transmission which concerns on this invention. It is a figure which shows the thrust ratio correction | amendment map corresponding to input torque of the control apparatus of the belt type continuously variable transmission which concerns on this invention. It is a figure which shows the vehicle speed corresponding | compatible thrust ratio correction map of the control apparatus of the belt-type continuously variable transmission which concerns on this invention. It is a figure which shows the oil temperature corresponding | compatible thrust ratio correction map of the control apparatus of the belt-type continuously variable transmission which concerns on this invention. It is a flowchart which shows the control structure of the control program performed by ECU.

  Embodiments of a control device for a belt type continuously variable transmission according to the present invention will be described below with reference to the drawings.

  FIGS. 1-7 is a figure which shows one Embodiment of the control apparatus of the belt-type continuously variable transmission which concerns on this invention. First, the configuration will be described.

  With reference to FIG. 1, a power train of a vehicle on which a continuously variable transmission according to the present embodiment is mounted will be described. As shown in FIG. 1, the power train of this vehicle includes an engine 10, a continuously variable transmission 35, and a differential gear 80.

  The continuously variable transmission 35 includes a torque converter 20, a forward / reverse switching device 29, a belt-type continuously variable transmission mechanism 30, an ECU (Electronic Control Unit) 100, and a hydraulic control unit 107.

  The output shaft of the engine 10 is connected to the input shaft of the torque converter 20. The engine 10 and the torque converter 20 are connected by a rotating shaft. Therefore, the output shaft rotational speed NE (engine rotational speed NE) of the engine 10 detected by the engine rotational speed sensor 44 and the input shaft rotational speed (pump rotational speed) of the torque converter 20 are the same.

  The torque converter 20 includes a lockup clutch 21 that directly connects the input shaft and the output shaft, a pump impeller 22 on the input shaft side, a turbine impeller 23 on the output shaft side, and a one-way clutch 25. And a stator 24 that exhibits an amplification function.

  The torque converter 20 and the belt type continuously variable transmission mechanism 30 are connected by a rotating shaft. An output shaft rotational speed NT (turbine rotational speed NT) of the torque converter 20 is detected by a turbine rotational speed sensor 40.

  An oil pump 26 is provided between the torque converter 20 and the belt type continuously variable transmission mechanism 30. The oil pump 26 is a gear pump, for example, and is operated as the pump impeller 22 on the input shaft side rotates. The oil pump 26 supplies oil to the line pressure control unit 110.

  The belt type continuously variable transmission mechanism 30 is connected to the torque converter 20 with a forward / reverse switching device 29 interposed therebetween. The belt-type continuously variable transmission mechanism 30 includes an input-side primary pulley 50, an output-side secondary pulley 60, and a metal annular belt 70 that is wound around the primary pulley 50 and the secondary pulley 60. Yes.

  The belt 70 is formed by arranging a plurality of elements having contact surfaces with the primary pulley 50 and the secondary pulley 60 in an annular shape.

  The primary pulley 50 includes a fixed sheave fixed to the primary shaft 51 and a movable sheave supported on the primary shaft 51 so as to be slidable only.

  The secondary pulley 60 includes a fixed sheave fixed to the secondary shaft 61 and a movable sheave supported by the secondary shaft 61 so as to be slidable only.

  Oil is supplied to and discharged from the primary hydraulic actuator 55 of the primary pulley 50. In addition, oil is supplied to and discharged from the secondary hydraulic actuator 65 of the secondary pulley 60.

  In the belt type continuously variable transmission mechanism 30, by continuously changing the groove width between the fixed sheave and the movable sheave of each pulley 50, 60, the winding radius of the belt 70 is changed to be larger or smaller. Shifting is performed.

  In the belt-type continuously variable transmission mechanism 30, the oil supplied to and discharged from the primary hydraulic actuator 55 and the secondary hydraulic actuator 65 and the oil supplied to the belt 70 are the same.

  This common oil is generally referred to as CVT fluid, and functions as hydraulic oil in the hydraulic system such as the primary hydraulic actuator 55 and the secondary hydraulic actuator 65. It is used to obtain lubrication and frictional force (slip prevention function) between the primary pulley 50 and the secondary pulley 60.

  The hydraulic control unit 107 presses the movable sheave of the primary pulley 50 toward the fixed sheave side to generate a thrust necessary for sandwiching the belt 70 (hereinafter referred to as a primary thrust). The hydraulic pressure supplied to the engine (hereinafter referred to as primary hydraulic pressure) is controlled.

  Further, the hydraulic pressure control unit 107 presses the movable sheave of the secondary pulley 60 toward the fixed sheave side to generate a thrust (hereinafter referred to as “secondary thrust”) necessary for pinching the belt 70 so as to develop the secondary hydraulic pressure of the secondary pulley 60. The hydraulic pressure supplied to the actuator 65 (hereinafter referred to as secondary hydraulic pressure) is controlled.

  The rotation speed NIN of the primary pulley 50 of the belt-type continuously variable transmission mechanism 30 (hereinafter referred to as primary pulley rotation speed NIN) is detected by the primary pulley rotation speed sensor 41, and the rotation speed NOUT of the secondary pulley 60 (hereinafter referred to as secondary). The pulley rotation speed NOUT) is detected by the secondary pulley rotation speed sensor 42.

  The primary pulley rotation speed sensor 41 and the secondary pulley rotation speed sensor 42 are provided to face the rotation detection gear teeth attached to the rotation shafts of the primary pulley 50 and the secondary pulley 60 and the drive shaft connected thereto. .

  The primary pulley rotation speed sensor 41 and the secondary pulley rotation speed sensor 42 can detect slight rotations of the primary pulley 50 as an input shaft and the secondary pulley 60 as an output shaft in the belt-type continuously variable transmission mechanism 30. For example, a sensor using a magnetoresistive element generally called a semiconductor sensor.

  In the belt type continuously variable transmission mechanism 30, a CVT oil temperature sensor 47 that detects the oil temperature of the oil is provided in the middle of a pipe that supplies oil from the oil pump 26 to the line pressure control unit 110.

  The oil temperature detected by the CVT oil temperature sensor 47 is output to the ECU 100 and used for correcting a thrust ratio map, which will be described later. Since the oil supplied to and discharged from the primary hydraulic actuator 55 and the secondary hydraulic actuator 65 and the oil supplied to the belt 70 are the same, the CVT oil temperature sensor 47 is supplied to the belt 70. Or a pipe for supplying and discharging oil to and from the primary hydraulic actuator 55 and the secondary hydraulic actuator 65, and the CVT oil temperature sensor 47 may detect the oil temperature at these locations.

  The forward / reverse switching device 29 includes a double pinion planetary gear, a reverse (reverse) brake B1, and an input clutch C1. In the planetary gear, its sun gear is connected to the input shaft, the carrier CR supporting the first and second pinions P1, P2 is connected to the primary side fixed sheave, and the ring gear R is a reverse friction engagement element. The reverse brake B1 is connected, and an input clutch C1 is interposed between the carrier CR and the ring gear R.

  The input clutch C1 is also called a forward clutch or a forward clutch, and is always used in an engaged state when a vehicle other than the parking (P) position, R position, and N position moves forward.

  The ECU 100 and the hydraulic control unit 107 that control the continuously variable transmission 35 will be described. The ECU 100 receives a signal representing the turbine rotational speed NT from the turbine rotational speed sensor 40, receives a signal representing the primary pulley rotational speed NIN from the primary pulley rotational speed sensor 41, and receives a secondary pulley rotational speed from the secondary pulley rotational speed sensor 42. A signal representing the number NOUT is input.

  The ECU 100 calculates the gear ratio from gear ratio = primary pulley rotation speed NIN / secondary pulley rotation speed NOUT. Further, the ECU 100 receives a signal representing the actual secondary hydraulic pressure in the secondary hydraulic actuator 65 from the secondary hydraulic sensor 43.

  The hydraulic control unit 107 includes a primary pressure control unit 108, a secondary pressure control unit 109, a line pressure control unit 110, a lockup engagement pressure control unit 111, a clutch pressure control unit 112, and a manual valve 113. ing.

  The ECU 100 controls the primary pressure control linear solenoid 120, the secondary pressure control linear solenoid 122, the line pressure control linear solenoid 123, and the lockup engagement pressure control duty solenoid 124 of the hydraulic control unit 107. A signal is output.

  The primary pressure control unit 108 controls the hydraulic pressure supplied to the primary hydraulic actuator 55 of the primary pulley 50 by the primary pressure control linear solenoid 120 so that the primary hydraulic pressure becomes the target hydraulic pressure.

  The secondary pressure control unit 109 controls the hydraulic pressure supplied to the secondary hydraulic actuator 65 of the secondary pulley 60 by the secondary pressure control linear solenoid 122 so that the secondary hydraulic pressure becomes the target hydraulic pressure. The target hydraulic pressure of the primary hydraulic pressure and the secondary hydraulic pressure is set according to the state of the vehicle. A method for setting the target hydraulic pressure will be described later.

  The line pressure control unit 110 includes an instruction value for the secondary pressure control linear solenoid 122 corresponding to the secondary pressure, and an instruction value for the primary pressure control linear solenoid 120 corresponding to the primary hydraulic pressure (estimated value or actual measurement value) or the primary pressure. Therefore, the line pressure is controlled by the line pressure control linear solenoid 123.

  In the present embodiment, the “line pressure” is the original pressure of the hydraulic pressure supplied to the primary hydraulic actuator 55 and the hydraulic pressure of the oil supplied to the secondary hydraulic actuator 65, and the hydraulic pressure generated by the oil pump 26 is the regulator valve. (Not shown) and the hydraulic pressure adjusted by the linear solenoid 123 for line pressure control.

  The line pressure controlled by the line pressure control unit 110 is supplied to the primary pressure control linear solenoid 120 and the secondary pressure control linear solenoid 122. In the primary pressure control unit 108 and the secondary pressure control unit 109, the primary hydraulic pressure and the secondary hydraulic pressure are controlled using the supplied line pressure.

  The lockup engagement pressure control unit 111 controls switching between engagement and release of the lockup clutch 21 and the gradual increase and decrease of the engagement pressure of the lockup clutch 21 by the lockup engagement pressure control duty solenoid 124. It is like that.

  The manual valve 113 operates in conjunction with the driver's operation of the shift lever to switch the oil passage. The clutch pressure control unit 112 controls the hydraulic pressure supplied via the manual valve 113 by the line pressure control linear solenoid 123 when the input clutch C1 or the reverse brake B1 is engaged.

  The ECU 100 further includes a signal representing the vehicle speed from the wheel speed sensor 45, a signal representing the depression amount of the accelerator pedal 48 from the accelerator pedal stroke sensor 46, and the engine speed (NE) from the engine speed sensor 44. Are respectively input.

  The ECU 100 includes a CPU (Central Processing Unit) (not shown) and a memory 101. Various information, programs, threshold values, maps, and the like are stored in the memory 101, and data is read or stored by the CPU as necessary.

  The wheel speed sensor 45 detects the rotational speed of a wheel (not shown). The wheel speed sensor 45 transmits a wheel speed signal indicating the detected number of rotations of the wheel to the ECU 100. In the present embodiment, as long as the vehicle speed can be detected, the present invention is not particularly limited to detecting the rotational speed of the wheel. For example, the secondary pulley rotational speed and the reduction ratio from the continuously variable transmission to the drive wheel The vehicle speed may be calculated based on the above.

  In the vehicle having the above configuration, the present invention is characterized in that the ECU 100 corrects the thrust ratio map according to the vehicle state.

  In the present embodiment, the ECU 100 corrects the thrust ratio map according to the input torque, the vehicle speed, and the oil temperature, and calculates the thrust ratio with reference to the corrected thrust ratio map.

  ECU 100 is based on a predetermined map (hereinafter referred to as a thrust ratio map) showing the relationship between the transmission ratio of continuously variable transmission 35 and the thrust ratio based on the thrust of primary pulley 50 and the thrust of secondary pulley 60. Thus, the hydraulic pressure of the primary hydraulic actuator 55 and the secondary hydraulic actuator 65 is controlled.

  The thrust ratio map defines the relationship among the safety factor SF (specifically, the torque ratio), the transmission ratio, and the thrust ratio. In the present embodiment, the “thrust ratio” is a ratio of primary thrust to secondary thrust. The thrust ratio map is stored in the memory 101 in advance.

  FIG. 2 shows a functional block diagram of ECU 100 that is the vehicle control apparatus according to the present embodiment. ECU 100 includes a shift control unit 106, a primary thrust correcting unit 102, an input torque corresponding thrust ratio map correcting unit 103, a vehicle speed corresponding thrust ratio map correcting unit 104, and an oil temperature corresponding thrust ratio map correcting unit 105. Consists of.

  The shift control unit 106 transmits an SLP control signal to the primary pressure control linear solenoid 120 of the hydraulic control unit 107 based on the vehicle state and the thrust ratio map, and SLS to the secondary pressure control linear solenoid 122. The transmission control of the continuously variable transmission 35 is performed by transmitting the control signal.

  Specifically, the shift control unit 106 calculates the target hydraulic pressure of the secondary hydraulic pressure based on the safety factor SF and the input torque for the primary pulley 50. The “input torque to the primary pulley 50” is, for example, the output torque of the engine 10 based on the amount of depression of the accelerator pedal 48 (signal from the accelerator pedal stroke sensor 46), the throttle opening, the rotational speed of the engine 10 or the intake air amount. And the torque ratio in the torque converter 20 may be estimated or may be detected directly.

  Note that the speed change control unit 106 may calculate the target oil pressure of the secondary oil pressure using a predetermined map, function, table, or the like that shows the relationship between the gear ratio, the input torque, and the target oil pressure of the secondary oil pressure. . A predetermined map, function, table, or the like may be adapted through experiments or the like.

  The intake air amount may be detected by an air flow meter (not shown), and the throttle opening may be detected by a slot position sensor (not shown).

  The shift control unit 106 calculates the safety factor SF from the calculated input torque and the actual secondary hydraulic pressure detected by the secondary hydraulic pressure sensor 43. The safety factor SF indicates the safety factor of the secondary thrust with respect to the actual input torque.

  For example, as the calculated input torque decreases, the safety factor SF increases as the degree of load on the continuously variable transmission 35 decreases (that is, the possibility of occurrence of a shift failure such as belt slip is low). . On the other hand, as the calculated input torque increases, the safety factor SF decreases as the degree of load on the continuously variable transmission 35 increases.

  Furthermore, the shift control unit 106 calculates the target gear ratio after calculating the target hydraulic pressure of the secondary hydraulic pressure. Specifically, the shift control unit 106 determines the target output of the engine based on the depression amount of the accelerator pedal 48 and the vehicle speed, and can realize the determined target output of the engine on the optimal fuel consumption line of the engine. A target gear ratio is calculated.

  The speed change control unit 106 calculates a thrust ratio with reference to the thrust ratio map shown in FIG. 3 according to the calculated safety factor SF and the target speed ratio. This thrust ratio map is a map set in advance corresponding to the safety factor SF, and defines the relationship among the safety factor SF, the gear ratio, and the thrust ratio. Further, as will be described later, the thrust ratio determined by this thrust ratio map is a thrust ratio base constant before the thrust ratio is corrected according to the input torque, the vehicle speed, and the oil temperature.

  In the thrust ratio map shown in FIG. 3, the horizontal axis represents the torque ratio, and the vertical axis represents the thrust ratio.

  In the thrust ratio map shown in FIG. 3, the horizontal axis is a drive region in which power is transmitted from the engine to the tire with the torque ratio being a positive value with 0.0 as a boundary. The left area where the ratio is negative is a driven area where power is transmitted from the tire to the engine and engine braking is generated.

  In the present embodiment, the thrust ratio map is generated by the input torque corresponding thrust ratio map correcting unit 103, the vehicle speed corresponding thrust ratio map correcting unit 104, and the oil temperature corresponding thrust ratio map correcting unit 105, which will be described later. It is corrected according to the oil temperature. The shift control unit 106 calculates the thrust ratio with reference to the corrected thrust ratio map.

  The input torque corresponding thrust ratio map correcting unit 103 corrects the thrust ratio map according to the input torque to the primary pulley 50. Specifically, the input torque corresponding thrust ratio map correction unit 103 refers to the input torque corresponding thrust ratio correction map shown in FIG. 4 and corrects the thrust ratio map according to the input torque.

  In the input torque corresponding thrust ratio correction map of FIG. 4, the horizontal axis indicates the torque ratio, the vertical axis indicates the thrust ratio correction amount, and the thrust ratio correction amount is determined according to a plurality of input torques. The thrust ratio correction amount is determined as a value to be subtracted from the thrust ratio of the thrust ratio map.

  In this input torque corresponding thrust ratio correction map, the thrust ratio correction amount increases as the input torque increases, and the thrust ratio correction amount increases as the torque ratio of the horizontal axis moves away from the drive region and the driven region. It has become. Further, in the input torque corresponding thrust ratio correction map, when the torque ratio on the horizontal axis is 0, the correction amount is 0 regardless of the input torque.

  The vehicle speed corresponding thrust ratio map correcting unit 104 corrects the thrust ratio according to the vehicle speed detected by the wheel speed sensor 45. Specifically, the vehicle speed corresponding thrust ratio map correction unit 104 refers to the vehicle speed corresponding thrust ratio correction map shown in FIG. 5 and corrects the thrust ratio according to the vehicle speed.

  In the vehicle speed corresponding thrust ratio correction map of FIG. 5, the horizontal axis indicates the torque ratio, the vertical axis indicates the thrust ratio correction amount, and the thrust ratio correction amount is determined according to a plurality of vehicle speeds. The thrust ratio correction amount is determined as a value to be subtracted from the thrust ratio of the thrust ratio map. Further, in the vehicle speed corresponding thrust ratio correction map, a signal indicating the rotational speed of the wheel detected by the wheel speed sensor 45 is used as the vehicle speed.

  In this vehicle speed corresponding thrust ratio correction map, the thrust ratio correction amount increases as the vehicle speed increases. The thrust ratio correction amount is constant regardless of the horizontal axis torque ratio at each vehicle speed.

  The oil temperature corresponding thrust ratio map correcting unit 105 corrects the thrust ratio map according to the oil temperature detected by the CVT oil temperature sensor 47. Specifically, the oil temperature corresponding thrust ratio map correction unit 105 refers to the oil temperature corresponding thrust ratio correction map shown in FIG. 6 and corrects the thrust ratio map according to the oil temperature.

  In the oil temperature corresponding thrust ratio correction map of FIG. 6, the horizontal axis indicates the torque ratio, the vertical axis indicates the thrust ratio correction amount, and the thrust ratio correction amount is determined according to a plurality of oil temperatures. The thrust ratio correction amount is determined as a value to be subtracted from the thrust ratio of the thrust ratio map.

  In this oil temperature corresponding thrust ratio correction map, the thrust ratio correction amount increases as the oil temperature increases. The thrust ratio correction amount is constant regardless of the torque ratio on the horizontal axis at each oil temperature.

  The shift control unit 106 refers to the thrust ratio map corrected by the input torque corresponding thrust ratio map correcting unit 103, the vehicle speed corresponding thrust ratio map correcting unit 104, and the oil temperature corresponding thrust ratio map correcting unit 105. A primary thrust is calculated according to the thrust. The shift control unit 106 calculates a target hydraulic pressure of the primary hydraulic pressure from the calculated primary thrust.

  Then, the transmission control unit 106 transmits an SLP control signal to the primary pressure control linear solenoid 120 so that the primary hydraulic pressure becomes the target hydraulic pressure. Furthermore, the shift control unit 106 transmits an SLS control signal to the secondary pressure control linear solenoid 122 so that the secondary hydraulic pressure becomes the target hydraulic pressure.

  The primary thrust correction unit 102 feeds back a deviation between the actual speed ratio detected by the primary pulley speed sensor 41 and the secondary pulley speed sensor 42 and the target speed ratio so that the actual speed ratio becomes equal to the target speed ratio. Furthermore, the primary hydraulic pressure is changed by correcting the SLP control signal for the linear solenoid 120 for primary pressure control.

  In the configuration in which the primary hydraulic pressure is corrected by feeding back the deviation between the actual gear ratio and the target gear ratio by the primary thrust correcting unit 102 as in the present embodiment, the deviation between the actual gear ratio and the target gear ratio is large. In addition, it may take time to correct the primary hydraulic pressure by the primary thrust correcting unit 102, which may impair the shift tracking performance. However, the input torque corresponding thrust ratio map correcting unit 103, the vehicle speed corresponding thrust ratio map correcting unit 104, By correcting the thrust ratio map according to the input torque, the vehicle speed, and the oil temperature by the oil temperature corresponding thrust ratio map correcting unit 105, the actual gear ratio becomes close to the target gear ratio. The amount of correction is reduced, and the shift tracking performance is improved.

  Hereinafter, with reference to FIG. 7, a control structure of a shift control program executed by ECU 100, which is the vehicle control apparatus according to the present embodiment, will be described.

  First, the ECU 100 calculates the target hydraulic pressure of the secondary hydraulic pressure based on the safety factor SF and the input torque to the primary pulley 50 (step S11), and outputs the secondary hydraulic pressure, that is, the secondary pressure so that the secondary hydraulic pressure becomes the target hydraulic pressure. An SLS control signal is output to the control linear solenoid 122 (step S12).

  Next, the ECU 100 calculates a target gear ratio based on the depression amount of the accelerator pedal 48 and the vehicle speed (step S13). Next, the ECU 100 corrects the thrust ratio map according to the input torque, the vehicle speed, and the oil temperature (step S14).

  Next, the ECU 100 calculates a thrust ratio with reference to the thrust ratio map corrected in step S14 according to the calculated target gear ratio and safety factor SF (step S15).

  Next, the ECU 100 calculates the primary thrust, that is, calculates the target hydraulic pressure of the primary hydraulic pressure according to the secondary thrust calculated in step S11 and the thrust ratio calculated in step S15 (step S16), and the primary hydraulic pressure is calculated. An SLP control signal is transmitted to the primary pressure control linear solenoid 120 so that the output, that is, the primary hydraulic pressure becomes the target hydraulic pressure (step S17).

  Next, the ECU 100 feeds back the deviation between the actual speed ratio and the target speed ratio, and corrects the primary hydraulic pressure so that the actual speed ratio becomes equal to the target speed ratio (step S18).

  As described above, in the present embodiment, the ECU 100 that controls the belt type continuously variable transmission mechanism 30 determines the thrust ratio according to at least one of the vehicle speed or the oil temperature of the oil supplied to the belt type continuously variable transmission mechanism 30. It consists of what corrects the map.

  With this configuration, the thrust ratio map is determined based on the corrected thrust ratio map by correcting the thrust ratio map according to at least one of the vehicle speed and the oil temperature, so that the actual thrust ratio is close to the target thrust. And the actual gear ratio is close to the target gear ratio. Therefore, the shift following ability can be improved.

  In the present embodiment, the ECU 100 that controls the belt-type continuously variable transmission mechanism 30 generates a thrust according to the vehicle speed on the basis of a vehicle speed corresponding thrust ratio correction map in which the relationship between the gear ratio, the thrust ratio, and the vehicle speed is predetermined. It is comprised from what performs correction of a ratio map.

  With this configuration, the thrust ratio is determined by a thrust ratio map that takes into account the vehicle speed that affects the friction coefficient between the belt 70, the primary pulley 50, and the secondary pulley 60, and the actual thrust ratio is close to the target thrust. As a result, the actual gear ratio becomes close to the target gear ratio, and the shift tracking performance can be improved.

  In the present embodiment, the ECU 100 that controls the belt-type continuously variable transmission mechanism 30 adjusts the oil temperature based on the oil temperature corresponding thrust ratio correction map in which the relationship between the gear ratio, the thrust ratio, and the oil temperature is predetermined. It is comprised from what corrects the thrust ratio map according to.

  With this configuration, the thrust ratio is determined by the thrust ratio map that takes into account the oil temperature that affects the friction coefficient between the belt 70, the primary pulley 50, and the secondary pulley 60, and the actual thrust ratio becomes the target thrust. As a result, the actual speed ratio becomes closer to the target speed ratio, and the shift tracking performance can be improved.

  As described above, the present invention can improve the shift following ability, and in particular, a belt type continuously variable transmission that continuously changes the gear ratio by controlling the thrust ratio between the primary pulley and the secondary pulley. It is useful for the control device.

30 Belt type continuously variable transmission mechanism (belt type continuously variable transmission)
35 continuously variable transmission 40 turbine speed sensor 41 primary pulley speed sensor 42 secondary pulley speed sensor 43 secondary oil pressure sensor 44 engine speed sensor 45 wheel speed sensor 46 accelerator pedal stroke sensor 47 CVT oil temperature sensor 48 accelerator pedal 50 primary Pulley 55 Primary hydraulic actuator 60 Secondary pulley 65 Secondary hydraulic actuator 70 Belt 100 ECU (Electronic Control Unit) (control device)
DESCRIPTION OF SYMBOLS 102 Primary thrust correction | amendment part 103 Input torque corresponding | compatible thrust ratio map correction | amendment part 104 Vehicle speed corresponding | compatible thrust ratio map correction | amendment part 105 Oil temperature corresponding | compatible thrust ratio map correction | amendment part 106 Shift control part 107 Hydraulic control part (control apparatus)

Claims (3)

A belt type continuously variable transmission control device that continuously changes the gear ratio by controlling the thrust ratio of the primary pulley and the secondary pulley based on a thrust ratio map in which the relationship between the gear ratio and the thrust ratio is determined in advance. There,
A control device for a belt-type continuously variable transmission, wherein the thrust ratio map is corrected according to at least one of a vehicle speed or an oil temperature of oil supplied to the belt-type continuously variable transmission.   2. The thrust ratio map according to the vehicle speed is corrected based on a vehicle speed corresponding thrust ratio correction map in which a relationship among the speed ratio, the thrust ratio, and the vehicle speed is determined in advance. Control device for belt type continuously variable transmission.   The correction of the thrust ratio map according to the oil temperature is performed based on an oil temperature corresponding thrust ratio correction map in which a relationship among the transmission ratio, the thrust ratio, and the oil temperature is predetermined. A control device for a belt-type continuously variable transmission according to claim 1.

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