JP4868024B2 - Control device for belt type continuously variable transmission - Google Patents

Description

  The present invention has a belt that has first and second pulleys and belts that span the pulleys, and that changes the gear ratio by changing the belt winding radius of both pulleys by controlling the thrust applied to both pulleys. The present invention relates to a control device for a continuously variable transmission.

  In recent years, as a vehicle-mounted transmission, it has first and second pulleys and belts stretched around these pulleys, and by changing the belt winding radius of both pulleys by controlling the thrust applied to both pulleys. Belt-type continuously variable transmissions that change the gear ratio have been put into practical use. Conventionally, a control device described in Patent Document 1 is known as a control device for such a belt type continuously variable transmission.

  In the control device for a belt-type continuously variable transmission described in Patent Document 1, thrust (hydraulic pressure) applied to a driving pulley is controlled by feedforward control and feedback control. And in the control apparatus of the literature 1, the sum of a steady thrust and a transient thrust is set to a feedforward instruction | indication thrust, and the said feedforward control is performed. Here, the steady thrust is set as the quotient of the target value of the thrust applied to the second pulley and the thrust ratio calculated according to the target gear ratio, and the transient thrust is the actual output of the belt type continuously variable transmission. It is set according to the amount of change in the ratio of the target input shaft rotational speed to the rotational speed. Further, in the control device of Patent Document 1, the feedback instruction thrust is set according to the deviation between the actual value of the input shaft rotational speed of the belt-type continuously variable transmission and the target value, and the above-described feedback control is performed.

JP 2005-344856 A JP 2006-226513 A

  In such a conventional belt-type continuously variable transmission control device, feedforward control of the thrust applied to the drive pulley is performed using a transient thrust set according to the amount of change in the ratio of the target input shaft rotational speed to the actual output rotational speed. Therefore, it is possible to appropriately control the speed of change of the speed ratio during the speed change, and to improve the response ratio of the speed ratio. However, such a conventional belt-type continuously variable transmission control device cannot easily ignore the following problems.

  In other words, the output rotational speed of the belt-type continuously variable transmission during gear shifting may fluctuate in a vibrational manner due to the influence of disturbance such as undulations on the road surface. When the output rotational speed fluctuates in this way, the value of the transient thrust set in accordance with the amount of change in the ratio of the target input shaft rotational speed to the output rotational speed, and thus the thrust applied to the drive pulley, fluctuates fluctuatingly. become. As a result, the behavior of the input rotational speed of the belt type continuously variable transmission during shifting becomes unstable.

  Patent Document 2 describes a control device for a belt-type continuously variable transmission that performs feedforward control of drive pulley thrust by setting feedforward command thrust according to oil inflow and outflow velocities. In this control device, when a disturbance is detected, the feedforward control of the drive pulley thrust is stopped, or the gain of the feedforward control amount with respect to the inflow and outflow velocities is reduced.

  If the feedforward control of the thrust applied to the drive pulley of the control device for the belt-type continuously variable transmission of Document 1 is stopped when disturbance is detected following the control device of Patent Document 2, fluctuations in the output shaft rotational speed are detected. Even at times, the input rotational speed of the belt type continuously variable transmission does not become unstable. However, in this case, since all of the feedforward control is stopped, a decrease in responsiveness is unavoidable. On the other hand, in the control device for the belt type continuously variable transmission of the above-mentioned document 1, if the gain of the feedforward command thrust is reduced when the output shaft rotational speed varies, the instability of the input shaft rotational speed is suppressed to some extent. It becomes possible. However, in this case as well, the output shaft rotational speed of the belt-type continuously variable transmission is used for the calculation of the feedforward command thrust, and it is given to the input shaft rotational speed of the belt-type continuously variable transmission during shifting. The effect of fluctuations in the output shaft rotation speed cannot be completely eliminated.

  The present invention has been made in view of such circumstances, and the problem to be solved is that the behavior of the input shaft rotational speed of the belt-type continuously variable transmission even when the output shaft rotational speed fluctuates. It is an object of the present invention to provide a control device for a belt-type continuously variable transmission capable of stabilizing the transmission.

Hereinafter, means for solving the above-described problems and the effects thereof will be described.
In order to solve the above-mentioned problem, the invention described in claim 1 includes first and second pulleys and belts that are stretched around the pulleys, and belt winding of both pulleys by controlling the thrust applied to both pulleys. A belt type continuously variable transmission that changes a gear ratio by changing a radius, and a target input shaft for a steady thrust set according to a target gear ratio and an actual output rotational speed of the belt type continuously variable transmission In the control device for a belt-type continuously variable transmission that performs shift control by setting the sum of the transient thrust set according to the amount of change in the rotation speed ratio to the feedforward command thrust of the first pulley, When detecting fluctuations in the output shaft rotational speed of the continuously variable transmission, a feedforward command thrust setting means at the time of rotational fluctuation is provided which sets the steady thrust to the feedforward command thrust. It has as its gist that.

  In the above configuration, the first and second pulleys and the belts that span the pulleys are provided, and the gear ratio is changed by changing the belt winding radius of both pulleys by controlling the thrust applied to both pulleys. I have to. Normally, the speed change control at this time depends on the amount of change in the target speed ratio calculated as the ratio of the steady thrust set according to the speed ratio control target and the target input shaft speed to the actual output speed. This is done by setting the sum of the transient thrust set to the feed forward command thrust of the first pulley. If the above-described transient thrust is employed as a calculation term for the feed-forward instruction thrust, it is possible to appropriately control the speed of change of the speed ratio during the speed change, and to increase the speed ratio response. However, since the actual output rotational speed of the belt-type continuously variable transmission is used for the calculation of the transient thrust, if the output shaft rotational speed of the belt-type continuously variable transmission fluctuates during shifting, the value is As a result, the feed-forward command thrust fluctuates in a vibrational manner, and the behavior of the input shaft rotational speed becomes unstable.

  In that respect, in the above-described configuration, when the fluctuation of the output shaft rotation speed is detected, the reflection of the transient thrust is stopped, and the steady thrust is set as the feedforward instruction thrust as it is. The steady thrust is set according to the target gear ratio. The target gear ratio is obtained as a ratio between the actual output of the belt type continuously variable transmission and the target input rotation speed. Therefore, the effect of fluctuations in the output rotation speed of the belt type continuously variable transmission also appears to some extent in the steady thrust value. However, since the actual value of the target gear ratio is used for the calculation of the steady thrust, not the differential value of the target gear ratio, the influence is limited. Therefore, even if the output shaft rotational speed of the belt type continuously variable transmission fluctuates, the value of the feedforward instruction thrust does not change in vibration. Therefore, according to the above configuration, the behavior of the input shaft rotation speed of the belt-type continuously variable transmission can be stabilized even when the output shaft rotation speed fluctuates.

  According to a second aspect of the present invention, there is provided a control device for the belt-type continuously variable transmission according to the first aspect, wherein the control device uses a feedback command thrust of the first pulley as a shift of the belt-type continuously variable transmission. The feedback instruction thrust is set based on the deviation between the actual value of the ratio and the target value, and when the fluctuation of the output shaft rotational speed of the belt type continuously variable transmission is detected, the input shaft rotational speed of the belt type continuously variable transmission The gist of the present invention is that it includes a rotation instruction feedback instruction thrust setting means that is set based on the deviation between the actual value and the target value.

  In the above configuration, the thrust control of the first pulley is performed using the feedback command thrust in addition to the feedforward command thrust. Normally, the feedback instruction thrust is set based on the deviation between the actual value of the speed ratio of the belt-type continuously variable transmission and the target value. However, the actual value of the transmission ratio varies depending on the variation of the output shaft rotation speed of the belt type continuously variable transmission. For this reason, if the feedback command thrust set as described above is used for thrust control of the first pulley, the value of the feedback command thrust fluctuates fluctuating with the variation of the output shaft rotational speed of the belt-type continuously variable transmission. It becomes like this.

  In that respect, in the above configuration, when a change in the output shaft rotational speed of the belt-type continuously variable transmission is detected, instead of the deviation between the actual value of the speed ratio of the belt-type continuously variable transmission and the target value, the belt-type continuously variable transmission The feedback command thrust is set using the deviation between the actual value of the input shaft rotation speed of the continuously variable transmission and the target value. Therefore, when the output shaft rotational speed of the belt type continuously variable transmission varies, the feedback instruction thrust is set regardless of the output shaft rotational speed. Therefore, according to the above configuration, when the thrust control of the first pulley is performed using the feedback instruction thrust set based on the deviation between the actual value of the speed ratio of the belt type continuously variable transmission and the target value, the output shaft rotates. It becomes possible to stabilize the behavior of the input shaft rotation speed of the belt type continuously variable transmission when the speed fluctuation occurs.

The steady thrust can be set as a quotient of a target value of the thrust applied to the second pulley and a thrust ratio calculated according to the target gear ratio.
Further, when the applied thrust of the first pulley is controlled as described above, the thrust applied to the second pulley as described in claim 4 should be set to a value at which a belt clamping pressure capable of suppressing belt slip is obtained. By controlling, it becomes possible to perform suitable shift control.

  Such a control device of the present invention can be applied to a hydraulically driven belt-type continuously variable transmission that generates hydraulic thrust applied to the first and second pulleys as described in claim 5. It is.

BRIEF DESCRIPTION OF THE DRAWINGS The schematic which shows typically the whole structure about the control apparatus of the belt-type continuously variable transmission which concerns on one Embodiment of this invention. The flowchart which shows the process sequence of the electronic control unit in the primary pulley thrust control routine employ | adopted as the same embodiment. The time chart which shows the control aspect of this embodiment at the time of the non-fluctuation of an output shaft rotational speed. The time chart which shows the control aspect of this embodiment and the conventional control apparatus at the time of the fluctuation | variation of an output shaft rotational speed, respectively.

Hereinafter, an embodiment of a control device for a belt type continuously variable transmission according to the present invention will be described in detail with reference to FIGS.
FIG. 1 shows the overall structure of a control device for a belt-type continuously variable transmission according to this embodiment. As shown in the figure, the belt-type continuously variable transmission includes two pulleys arranged with a fixed interval with the rotation axis in parallel, that is, a primary pulley 1 as a first pulley and a second pulley as a first pulley. A secondary pulley 2 and a metal belt 3 wound around the two pulleys are provided. Each pulley (1, 2) is composed of a fixed sheave fixed in the axial direction and a movable sheave arranged so as to be movable back and forth in the axial direction, according to the thrust (sheave pressure) applied to the movable sheave. Thus, the wrapping radius of the belt 3 is variable.

  Such a belt-type continuously variable transmission is controlled by the electronic control unit 4. The electronic control unit 4 includes a CPU that performs various arithmetic processes related to the shift control, a ROM that stores programs and data for shift control, a RAM that temporarily stores CPU calculation results and detection results of various sensors, It is provided with I / O for exchanging signals.

  The electronic control unit 4 controls the speed ratio of the belt type continuously variable transmission through the control of the hydraulic circuit. The hydraulic circuit includes first and second solenoids 5 and 7, a first flow control valve 6 and a second flow control valve 8. Here, the first and second solenoids 5 and 7 are configured as electromagnetic valves that output a command pressure based on a command signal from the electronic control unit 4. The first flow control valve 6 is a valve that adjusts the line pressure PL according to the command pressure output from the first solenoid 5 to form a sheave pressure that is applied to the primary pulley 1. The valve 8 is a valve that adjusts the line pressure PL according to the command pressure output from the second solenoid 7 to form a sheave pressure applied to the secondary pulley 2.

  The electronic control unit 4 includes an accelerator sensor 9 that detects an accelerator operation amount, a vehicle speed sensor 10 that detects a vehicle speed, an input shaft rotational speed sensor 11 that detects an input shaft rotational speed of a belt-type continuously variable transmission, and the transmission. The detection signal of the output shaft rotational speed sensor 12 for detecting the output shaft rotational speed is input. The electronic control unit 4 also includes detection signals such as a first sheave pressure sensor 13 that detects the sheave pressure applied to the primary pulley 1 and a second sheave pressure sensor 14 that detects the sheave pressure applied to the secondary pulley 2. Have been entered.

  Such an electronic control unit 4 calculates a gear ratio that is optimal for the current vehicle traveling state based on the accelerator operation amount and the vehicle speed, and controls the hydraulic circuit to realize the gear ratio. The electronic control unit 4 at this time determines the sheave pressure (secondary sheave pressure) applied to the secondary pulley 2 as follows. That is, the electronic control unit 4 calculates the value of the belt clamping pressure that can prevent the belt 3 from slipping on the secondary pulley 2 from the state of both pulleys at that time, and the secondary sheave pressure so that the belt clamping pressure can be obtained. To control. That is, the thrust applied to the secondary pulley 2 is controlled so as to obtain a belt clamping pressure that can prevent the belt 3 from slipping.

  On the other hand, the thrust applied to the primary pulley 1, that is, the primary sheave pressure is controlled so as to achieve a target gear ratio. Control of the primary sheave pressure at this time is performed by feedforward control and feedback control. Normally, the electronic control unit 4 uses a feedforward command thrust related to the feedforward control of the primary sheave pressure as a steady thrust set according to a target gear ratio of the belt type continuously variable transmission, and a belt type continuously variable transmission. Shift control is performed by setting the sum to the transient thrust set in accordance with the amount of change in the target γ, which is the ratio of the target input shaft rotational speed to the actual output rotational speed of the machine. The steady thrust is a thrust calculated according to the target value of the applied thrust (secondary sheave pressure) of the secondary pulley 2 set so as to obtain a belt clamping pressure capable of preventing the belt 3 from slipping and the target gear ratio. It is set as a quotient with the ratio.

  On the other hand, the electronic control unit 4 performs the feedback control of the primary sheave pressure by setting the feedback instruction thrust based on the deviation between the actual value of the speed ratio of the belt type continuously variable transmission and the target value. That is, the electronic control unit 4 feedback-controls the primary sheave pressure so that the deviation between the actual value of the gear ratio and the target value is reduced.

  By performing the feed forward control and the feedback control of the primary sheave pressure in such a manner, normally, the shift control of the belt type continuously variable transmission can be suitably performed. However, in such a control mode, if a change in the output shaft rotational speed of the belt-type continuously variable transmission due to disturbance such as undulations on the road surface occurs during the shift, the input shaft rotational speed of the belt-type continuously variable transmission becomes unstable. End up. That is, both the feedforward instruction thrust and the feedback instruction thrust are calculated based on the output shaft rotational speed of the belt-type continuously variable transmission. Therefore, when the output shaft rotational speed of the belt-type continuously variable transmission fluctuates in a vibrational manner, the values of the feedforward instruction thrust and the feedback instruction thrust calculated using the values also fluctuate in a vibrational manner. As a result, the input shaft rotational speed of the belt type continuously variable transmission fluctuates in an unstable manner.

  Therefore, in the present embodiment, the electronic control unit 4 detects the fluctuation of the output shaft rotation speed from the detection result of the output shaft rotation speed sensor 12, and changes the contents of the feedforward control and feedback control at the time of detection. I am doing so. Specifically, the electronic control unit 4 performs the feed forward control of the primary sheave pressure by setting the steady thrust as the feed forward instruction thrust as it is when detecting the fluctuation of the output shaft rotation speed. Further, the electronic control unit 4 sets the feedback instruction thrust based on the deviation between the actual value of the input shaft rotational speed of the belt-type continuously variable transmission and the target value when detecting the fluctuation of the output shaft rotational speed, and the primary sheave pressure. Feedback control is performed. In such a case, the feedback instruction thrust is set regardless of the output shaft rotational speed of the belt type continuously variable transmission. In addition, the differential value of the output shaft rotation speed of the belt-type continuously variable transmission is not used in the calculation of the feedforward command thrust at this time, and the effect of fluctuations in the output shaft rotation speed on the value of the feedforward command thrust Will be limited. Therefore, it is possible to prevent the fluctuation of the output shaft rotation speed from being superimposed on the values of the feedforward instruction thrust and the feedback instruction thrust, thereby avoiding instability of the input shaft rotation speed.

  FIG. 2 shows a flowchart of a primary pulley thrust control routine for controlling the primary sheave pressure, that is, the applied thrust of the primary pulley 1. The processing of this routine is repeatedly performed by the electronic control unit 4 periodically.

  When this routine is started, the electronic control unit 4 first checks in step S100 whether a change in the output shaft rotational speed of the belt type continuously variable transmission has been detected. If the fluctuation of the output shaft rotation speed is not detected (S100: NO), the electronic control unit 4 proceeds to the process of step S101. In step S101, the electronic control unit 4 sets the sum of the steady thrust and the transient thrust as the feedforward command thrust Winff. In step S102, the electronic control unit 4 sets a feedback control amount calculated according to a deviation between the actual value of the gear ratio and the target value as the feedback instruction thrust Winfb. In step S105, the electronic control unit 4 sets the sum of the feedforward command thrust Winff and the feedback command thrust Winfb set in this way to the applied thrust (primary sheave pressure) of the primary pulley 1, and the processing of this routine this time Exit.

  On the other hand, if the fluctuation | variation of the output-shaft rotational speed is detected in step S100 (S100: YES), the electronic control unit 4 will progress to the process of step S103. In step S103, the electronic control unit 4 sets the steady thrust as it is as the feedforward command thrust Winff. Further, in the subsequent step S104, the electronic control unit 4 sets a feedback control amount calculated according to the deviation between the actual value of the input shaft rotation speed and the target value as the feedback instruction thrust Winfb. In step S105, the electronic control unit 4 sets the sum of the feedforward command thrust Winff and the feedback command thrust Winfb set in this way to the applied thrust (primary sheave pressure) of the primary pulley 1, and the processing of this routine this time Exit.

  FIG. 3 shows changes in the target input shaft rotational speed, the primary sheave pressure Pin, and the secondary sheave pressure Pout before and after the shift when there is no change in the output shaft rotational speed of the belt type continuously variable transmission. In the figure, the change of the gear ratio is started from time t1, and the gear shift to the target gear ratio is completed at time t2. During the period from time t1 to time t2 during the shift, the steady thrust that can be set to the target gear ratio in a steady state is set according to the amount of change in the target γ (= dγ / dt). A value obtained by adding a transient thrust is set as the primary sheave pressure Pin. The transient thrust at this time is set so that the speed of change of the gear ratio during shifting becomes an appropriate value and sufficient response can be obtained.

  FIG. 4 shows changes in the target input shaft rotational speed, the primary sheave pressure Pin, and the secondary sheave pressure Pout before and after the shift when a change in the output shaft rotational speed of the belt-type continuously variable transmission occurs during the shift. . As shown in the figure, during the period from the time t3 when the change of the gear ratio is started to the time t4 when the change of the gear ratio to the target gear ratio is completed, the target input shaft is changed according to the fluctuation of the output shaft rotation speed. The rotational speed value also fluctuates in a vibrational manner. Here, when the feedforward command thrust Winff and the feedback command thrust Winfb are set in the same manner as usual, as shown by a two-dot chain line in the figure, the fluctuation of the output shaft rotational speed is superimposed on the primary sheave pressure Pin. .

  On the other hand, in the present embodiment, when detecting fluctuations in the output shaft rotation speed, the feedforward instruction thrust Winff and the feedback instruction thrust Winfb are set without using any output shaft rotation speed. For this reason, the primary sheave pressure Pin is stably changed despite the fluctuation of the output shaft rotational speed, and the input shaft rotational speed of the belt-type continuously variable transmission is kept stable. .

  In this embodiment, the electronic control unit 4 corresponds to the rotation fluctuation feedforward instruction thrust setting means and the rotation fluctuation feedback instruction thrust setting means.

According to the control device for the belt-type continuously variable transmission of the present embodiment described above, the following effects can be obtained.
(1) A belt-type continuously variable transmission to which the present embodiment is applied has a primary pulley 1 and a secondary pulley 2 and a belt 3 stretched over these pulleys (1, 2), and both pulleys (1, 2). The gear ratio is changed by changing the belt wrapping radius of both pulleys (1, 2) by controlling the thrust applied to the pulley. Usually, the electronic control unit 4 is set according to the amount of change in the ratio of the steady thrust set according to the target gear ratio and the target input shaft rotational speed to the actual output rotational speed of the belt-type continuously variable transmission. The shift control is performed by setting the sum of the transient thrust and the feed forward command thrust Winff of the primary pulley 1. However, when detecting fluctuations in the output shaft rotation speed of the belt-type continuously variable transmission, the electronic control unit 4 performs the shift control by setting the steady thrust as it is to the feedforward instruction thrust Winff. If the above-described transient thrust is employed as a calculation term for the feedforward instruction thrust Winff, it is possible to appropriately control the speed of change of the speed ratio during the speed change, and thus increase the speed ratio response. . However, since the actual output rotational speed of the belt-type continuously variable transmission is used for the calculation of the transient thrust, if the output shaft rotational speed of the belt-type continuously variable transmission fluctuates, that value will eventually be fed forward. The command thrust changes in vibration, and the behavior of the input shaft rotational speed becomes unstable. In this regard, in the present embodiment, when the fluctuation of the output shaft rotation speed is detected, the reflection of the transient thrust is stopped and the steady thrust is set as it is as the feedforward command thrust Winff. The steady thrust is set according to the target gear ratio. The target gear ratio is obtained as a ratio between the actual output of the belt type continuously variable transmission and the target input rotation speed. Therefore, the effect of fluctuations in the output rotation speed of the belt type continuously variable transmission also appears to some extent in the steady thrust value. However, since the actual value of the target gear ratio is used for the calculation of the steady thrust, not the differential value of the target gear ratio, the influence is limited. Therefore, even if the output shaft rotational speed of the belt type continuously variable transmission fluctuates, the value of the feedforward instruction thrust does not change in vibration. Therefore, according to the present embodiment, the behavior of the input shaft rotational speed of the belt-type continuously variable transmission can be stabilized even when the output shaft rotational speed fluctuates.

  (2) In this embodiment, the electronic control unit 4 normally sets the feedback instruction thrust Winfb of the primary pulley 1 based on the deviation between the actual value of the speed ratio of the belt-type continuously variable transmission and the target value. Yes. However, since the actual value of the gear ratio fluctuates according to the fluctuation of the output shaft rotation speed of the belt type continuously variable transmission, the fluctuation of the output shaft rotation speed of the belt type continuously variable transmission remains unchanged. At the same time, the value of the feedback instruction thrust Winfb fluctuates in a vibrational manner. Therefore, in this embodiment, when detecting the fluctuation of the output shaft rotational speed of the belt type continuously variable transmission, the electronic control unit 4 uses the feedback instruction thrust Winfb as the actual value of the input shaft rotational speed of the belt type continuously variable transmission and the target. It is set based on the deviation from the value. Therefore, when the output shaft rotational speed of the belt type continuously variable transmission varies, the feedback instruction thrust Winfb is set regardless of the output shaft rotational speed. Therefore, according to the present embodiment, when the thrust control of the primary pulley 1 is performed using the feedback instruction thrust Winfb set based on the deviation between the actual value of the speed ratio of the belt-type continuously variable transmission and the target value, It is possible to stabilize the behavior of the input shaft rotational speed of the belt type continuously variable transmission when the shaft rotational speed fluctuates.

In addition, the said embodiment can also be changed and implemented as follows.
In the above embodiment, the change in the output shaft rotational speed of the belt-type continuously variable transmission is detected from the detection result of the output shaft rotational speed sensor 12, but if such a sensor is not installed, the vehicle speed You may make it detect this from the detection result of other sensors, such as a sensor.

  In the above embodiment, the secondary sheave pressure is controlled so that the belt clamping pressure is a value that can prevent the belt 3 from slipping. However, the control mode of the secondary sheave pressure is not limited to this and is appropriately changed. May be. In short, if the secondary sheave pressure is controlled by adjusting the primary sheave pressure for changing the gear ratio, the effects of the above embodiment can be obtained regardless of the specific control contents. Is possible.

  In the above embodiment, the steady thrust is set as the quotient of the target value of the thrust applied to the secondary pulley 2 and the thrust ratio calculated according to the target gear ratio. However, the steady thrust only needs to be a thrust (primary sheave pressure) that provides a target gear ratio in a steady state, and if it is set according to the target gear ratio, the specific calculation mode is appropriately determined. It may be changed.

  In the above embodiment, the case where the primary pulley 1 is the first pulley and the secondary pulley 2 is the second pulley has been described, but this relationship may be reversed. In this case, shift control is performed based on feedforward control and feedback control of the applied thrust (secondary sheave pressure) of the secondary pulley 2 as the first pulley.

  In the above embodiment, the shift control is performed by both feedforward control and feedback control of the thrust applied to the first pulley. However, the shift control may be performed only by feedforward control. Even in this case, if the feedforward command thrust is normally set as the sum of the steady thrust and the transient thrust, and the fluctuation of the output shaft rotational speed is detected, the steady thrust is set as it is. It is possible to stabilize the behavior of the input shaft rotational speed of the belt type continuously variable transmission when the fluctuation occurs.

  In the above embodiment, the case where the control device according to the present invention is applied to a belt-type continuously variable transmission configured to generate hydraulic force applied to each pulley (1, 2) has been described. Also, the present invention can be applied to a belt-type continuously variable transmission that changes a gear ratio using a thrust other than hydraulic pressure in the same manner as in the above embodiment.

  DESCRIPTION OF SYMBOLS 1 ... Primary pulley (1st pulley), 2 ... Secondary pulley (2nd pulley), 3 ... Belt, 4 ... Electronic control unit (Feed forward instruction thrust setting means at the time of rotation fluctuation, Feedback instruction thrust setting means at the time of rotation fluctuation), DESCRIPTION OF SYMBOLS 5 ... 1st solenoid, 6 ... 1st flow control valve, 7 ... 2nd solenoid, 8 ... 2nd flow control valve, 9 ... Accelerator sensor, 10 ... Vehicle speed sensor, 11 ... Input rotational speed sensor, 12 ... Output rotational speed Sensor, 13 ... first sheave pressure sensor, 14 ... second sheave pressure sensor.

Claims (5)

Belt-type continuously variable transmission having first and second pulleys and belts spanning these pulleys, and changing the gear ratio by changing the belt winding radius of both pulleys by controlling the thrust applied to both pulleys A steady thrust set according to the target gear ratio, and a transient thrust set according to the amount of change in the ratio of the target input shaft rotational speed to the actual output rotational speed of the belt-type continuously variable transmission, In a control device for a belt-type continuously variable transmission that performs shift control by setting the sum of the above to the feedforward command thrust of the first pulley,
A belt-type continuously variable feed-forward command thrust setting means for setting the steady-state thrust to the feed-forward command thrust when detecting a change in the output shaft rotational speed of the belt-type continuously variable transmission. Transmission control device. The control device sets the feedback instruction thrust of the first pulley based on the deviation between the actual value and the target value of the gear ratio of the belt-type continuously variable transmission,
Rotational fluctuation that sets the feedback command thrust based on the deviation between the actual value and the target value of the input shaft rotational speed of the belt-type continuously variable transmission when detecting the fluctuation of the output shaft rotational speed of the belt-type continuously variable transmission The control device for a belt-type continuously variable transmission according to claim 1, further comprising hour feedback instruction thrust setting means. The belt-type continuously variable transmission according to claim 1, wherein the steady thrust is set as a quotient of a target value of thrust applied to the second pulley and a thrust ratio calculated in accordance with a target speed ratio. Machine control device. The belt-type continuously variable transmission according to any one of claims 1 to 3, wherein the thrust applied to the second pulley is controlled to a value at which a belt clamping pressure capable of suppressing slippage of the belt is obtained. Machine control device. The control device for a belt-type continuously variable transmission according to any one of claims 1 to 4, wherein the thrust applied to the first and second pulleys is generated by hydraulic pressure.

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