JP7393168B2 - Control device for continuously variable belt transmission and belt slip determination method for continuously variable belt transmission - Google Patents

Description

The present invention relates to a control device for a continuously variable belt transmission and a control method for a continuously variable belt transmission.

Patent Document 1 discloses a technique for determining that the belt is slipping when the gear ratio of a continuously variable belt transmission continues to be out of a range of mechanically possible gear ratios for a predetermined period of time.

Japanese Patent Application Publication No. 2004-124968

In the above technique, even if the belt is slipping, it cannot be determined that the belt is slipping if the gear ratio of the continuously variable belt transmission is within the range of mechanically possible gear ratios.

It is also possible to determine that the belt is slipping when the shifting speed is out of the normal shifting speed range, but with this method, even if the belt is slipping, the shifting speed remains within the normal shifting speed range. If the shifting speed is within the range of the ratio, it cannot be determined that the belt is slipping.

The present invention was made in view of such technical problems, and an object of the present invention is to improve belt slip detection performance.

According to an aspect of the present invention, there is provided a control device for a continuously variable belt transmission including a primary pulley, a secondary pulley, and a belt wound around the primary pulley and the secondary pulley, a control unit that determines belt slip of the continuously variable belt transmission based on a gear shift speed of the machine and a differential thrust between the primary pulley and the secondary pulley for setting the continuously variable belt transmission to a target gear ratio; the primary pulley and the Provided is a control device for a continuously variable belt transmission characterized in that the thrust force is the difference from the thrust force of a secondary pulley .

According to another aspect of the present invention, there is provided a belt slip determination method for a continuously variable belt transmission having a primary pulley, a secondary pulley, and a belt wound around the primary pulley and the secondary pulley, Belt slip of the belt continuously variable transmission based on the shifting speed of the belt continuously variable transmission and the differential thrust between the primary pulley and the secondary pulley for setting the belt continuously variable transmission to the target gear ratio. and the differential thrust is a balance thrust ratio that is a ratio of the thrust of the primary pulley and the thrust of the secondary pulley to set the belt continuously variable transmission to the current gear ratio. Provided is a belt slip determination method for a continuously variable belt transmission, characterized in that the belt slip is a difference from the thrust of a secondary pulley .

In these aspects, belt slip is determined based on the relationship between the gear shift speed and the differential thrust, so that if the gear ratio is within the range of normal gear ratios or the gear change speed is normal gear ratio. Belt slip can be determined even if it is within the range of . That is, belt slip detection performance can be improved.

FIG. 1 is a schematic diagram of a vehicle to which a control device for a continuously variable belt transmission according to an embodiment of the present invention is applied. FIG. 2 is a diagram for explaining belt slip determination. FIG. 3 is a flowchart showing the details of belt slip determination. FIG. 4 is a time chart showing how belt slip determination is performed.

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a schematic configuration diagram of a vehicle 100. Vehicle 100 includes an engine 1, an automatic transmission 3 as a continuously variable belt transmission, an oil pump 5, drive wheels 6, and a controller 10 as a control section.

The engine 1 is an internal combustion engine that uses gasoline, light oil, or the like as fuel, and functions as a driving source for driving. The rotational speed, torque, etc. of the engine 1 are controlled based on commands from the controller 10.

The automatic transmission 3 includes a torque converter 2, a fastening element 31, a variator 30, a hydraulic control valve unit 40 (hereinafter also simply referred to as "valve unit 40"), and an oil reservoir that stores oil (hydraulic oil). A bread 32 is provided.

Torque converter 2 is provided on a power transmission path between engine 1 and drive wheels 6. Torque converter 2 transmits power via fluid. Further, the torque converter 2 can increase the power transmission efficiency of the driving force from the engine 1 by engaging the lock-up clutch 2a.

The fastening element 31 is arranged on the power transmission path between the torque converter 2 and the variator 30. The fastening element 31 includes a forward clutch and a reverse brake (not shown). The fastening element 31 is controlled by oil whose pressure is regulated by the valve unit 40 using the discharge pressure of the oil pump 5 as a source pressure based on a command from the controller 10 . As the fastening element 31, for example, a normally open wet type multi-disc clutch is used.

The variator 30 is disposed on a power transmission path between the fastening element 31 and the drive wheels 6, and changes the gear ratio steplessly in accordance with vehicle speed, accelerator opening, and the like. The variator 30 includes a primary pulley 30a, a secondary pulley 30b, and a belt 30c wound around both pulleys 30a and 30b. By moving the movable pulley of the primary pulley 30a and the movable pulley of the secondary pulley 30b in the axial direction by pulley pressure and changing the pulley contact radius of the belt 30c, the speed ratio is changed steplessly. The pulley pressure acting on the primary pulley 30a and the pulley pressure acting on the secondary pulley 30b are regulated by the valve unit 40 using the discharge pressure from the oil pump 5 as the source pressure.

The differential 12 is connected to the output shaft of the secondary pulley 30b of the variator 30 via a final reduction gear mechanism (not shown). A drive wheel 6 is connected to the differential 12 via a drive shaft 13.

The oil pump 5 is driven by the rotation of the engine 1 being transmitted via a belt. The oil pump 5 is configured by, for example, a vane pump. The oil pump 5 sucks up oil stored in the oil pan 32 and supplies the oil to the valve unit 40. The oil supplied to the valve unit 40 is used for driving each pulley 30a, 30b, driving the fastening element 31, and lubricating each element of the automatic transmission 3.

The controller 10 is composed of a microcomputer including a central processing unit (CPU), a read-only memory (ROM), a random access memory (RAM), and an input/output interface (I/O interface). The controller 10 can also be configured with a plurality of microcomputers. Specifically, the controller 10 can be configured by an ATCU that controls the automatic transmission 3, an SCU that controls the shift range, an ECU that controls the engine 1, and the like. Note that the control unit in this embodiment is a virtual unit that has a function of executing belt slip determination control, which will be described later, of the controller 10.

The controller 10 includes a first rotation speed sensor 50 that detects the rotation speed of the engine 1 (=rotation speed on the input side of the torque converter 2), and a second rotation speed sensor 51 that detects the rotation speed on the output side of the torque converter 2. , a third rotation speed sensor 52 that detects the output rotation speed of the fastening element 31 (=rotation speed of the primary pulley 30a), a fourth rotation speed sensor 53 that detects the rotation speed of the secondary pulley 30b, and a vehicle speed sensor 54 that detects the vehicle speed. , a first oil pressure sensor 55 that detects the pulley pressure acting on the primary pulley 30a, a second oil pressure sensor 56 that detects the pulley pressure acting on the secondary pulley 30b, and a select range of the variator 30 (switching between forward, reverse, neutral, and parking). Signals are input from an inhibitor switch 57 that detects the state of the select lever or select switch, an accelerator opening sensor 58 that detects the accelerator opening APO, a pedal force sensor 59 that detects the brake pedal force, and the like. The controller 10 controls various operations of the engine 1 and automatic transmission 3 based on these input signals.

By the way, in the automatic transmission 3, the belt 30c may slip depending on the driving state of the vehicle 100 or the like. A method for determining whether slipping of the belt 30c has occurred is to determine that slipping of the belt 30c has occurred when the gear ratio of the automatic transmission 3 continues to be out of the mechanically possible range of gear ratios for a predetermined period of time. There is a way to judge.

However, with this determination method, even if the belt 30c is slipping, if the gear ratio of the automatic transmission 3 is within the range of mechanically possible gear ratios, it is difficult to determine that the belt 30c is slipping. Can not.

It is also possible to determine that the belt 30c is slipping when the shifting speed is out of the range of shifting speeds in normal shifting, but with this method, even if the belt 30c is slipping, the shifting speed is normal. If the speed change speed is within the range of the speed change ratio, it cannot be determined that the belt 30c is slipping.

Therefore, in this embodiment, the controller 10 executes belt slip determination control that determines belt slip based on the shift speed in the automatic transmission 3 and the differential thrust T between the primary pulley 30a and the secondary pulley 30b. Note that the belt slip determination control is executed based on a program stored in the controller 10 in advance.

Details of belt slip determination control by the controller 10 will be described with reference to FIGS. 2 to 4. FIG. 2 is a diagram for explaining belt slip determination. FIG. 3 is a flowchart showing the details of belt slip determination by the controller 10. FIG. 4 is a time chart showing how belt slip determination is performed.

First, an overview of belt slip determination will be described with reference to FIG. 2.

In FIG. 2, the vertical axis represents the speed change speed of the automatic transmission 3 (time rate of change in the speed ratio obtained by differentiating the speed ratio of the automatic transmission 3), and the horizontal axis represents the primary pulley 30a and the secondary pulley 30b. The differential thrust T is taken. In FIG. 2, the origin O indicates that the shift speed is 0 and the differential thrust T is also 0. The vertical axis indicates that the shift speed increases as the direction from the origin O goes to the plus side, and it indicates that the shift speed increases as the direction goes from the origin O to the minus side. In other words, the larger the absolute value of the vertical axis, the larger the shifting speed. Further, the horizontal axis indicates that the differential thrust T increases as the gear ratio shifts to the Low side as it goes from the origin O to the plus side, and the gear ratio shifts to the High side as it goes from the origin O to the minus side. This shows that the differential thrust T increases. Note that the shifting speed shown in FIG. 2 is a value within a range that can occur in the automatic transmission 3 in a normal case where belt slip does not occur.

The speed change of the automatic transmission 3 is determined by the differential thrust T between the primary pulley 30a and the secondary pulley 30b. That is, the shift speed and the differential thrust T are in a proportional relationship as shown by the line segment L in FIG. In the following description, the coefficient of the proportional relationship (the slope of the line segment L) will be referred to as a differential thrust characteristic coefficient.

Based on the above proportional relationship, when the differential thrust T is known, the shifting speed corresponding to the differential thrust (shifting speed in a normal case where belt slip does not occur; hereinafter referred to as estimated shifting speed ES) is also known. For example, as shown in FIG. 2, when the differential thrust T is x1, the estimated shift speed ES is found to be y1.

Here, when the actual shift speed (shift speed calculated based on the rotational speed of the pulleys 30a and 30b; hereinafter referred to as actual shift speed AS) when the predetermined differential thrust T is the predetermined differential thrust T, If the estimated shift speed ES is greater than the estimated shift speed ES, it can be considered that slippage of the belt 30c has occurred.

However, each individual automatic transmission 3 has a thrust ratio (hereinafter referred to as a balance thrust ratio) required to achieve a predetermined gear ratio, an oil pressure detection accuracy of the oil pressure sensors 55 and 56, and a predetermined There are variations in the response time from when the differential thrust T is reached until the pulleys 30a and 30b move to reach the predetermined gear ratio, and the differential thrust characteristic coefficient (the slope of the line segment L in FIG. 2) of the estimated shift speed ES. There is. Therefore, due to the influence of these variations, the actual shift speed AS may become larger than the estimated shift speed ES even when belt slip does not occur.

Therefore, in this embodiment, in order to prevent erroneous determination of belt slip, the estimated shifting speed Kmax is set as the maximum value of the estimated shifting speed ES that takes into account the above-mentioned variations, and the actual shifting speed AS at a predetermined differential thrust T is set as the maximum value of the estimated shifting speed ES. If the actual shift speed AS is larger than the estimated shift speed Kmax by comparing it with the estimated shift speed Kmax, it is determined that slipping of the belt 30c has occurred.

When the above estimated shift speed Kmax is plotted in FIG. 2, it becomes a line segment p and a line segment q. Note that the region N (the region from the origin O to the line segment C and the region from the origin O to the line segment D) is caused by variations in the balance thrust ratio in the automatic transmission 3 and variations in the oil pressure detection accuracy of the oil pressure sensors 55 and 56. This is a region where the differential thrust T cannot be measured accurately. Therefore, in region N, the estimated shift speed Kmax is not set. When the differential thrust T is in the region N (when the absolute value of the differential thrust T is less than or equal to the maximum value T(N) of the differential thrust T in the region N), belt slip is not determined. In other words, an area A that is more positive than line segment p in the vertical axis direction and more positive than line segment C in the horizontal axis direction, and an area A that is more negative than line segment q in the vertical axis direction and more than line segment D. A region B on the minus side in the horizontal axis direction is a region in which it is determined that the belt 30c is slipping.

For example, consider a case in which the differential thrust T is x1 and the actual shift speed AS is y2 in FIG. In this case, y2, which is the actual shift speed AS, is larger than y1, which is the estimated shift speed ES when the differential thrust T is x1, and is the maximum value Kmax(x1 ) is greater than. Therefore, in this case, it is determined that the belt 30c is slipping.

Next, consider the case where the actual shift speed AS is y3 when the differential thrust T is x1 in FIG. In this case, y3, which is the actual shift speed AS, is larger than y1, which is the estimated shift speed ES when the differential thrust T is x1, but the maximum value Kmax(x1) of the estimated shift speed ES takes into account variations in the automatic transmission 3. smaller than. That is, the deviation between the estimated shift speed ES and the actual shift speed AS in this case is considered to be due to variations in the automatic transmission 3 and not due to belt slip. Therefore, in this case, it is determined that no slipping of the belt 30c has occurred.

Next, referring mainly to FIG. 3, the details of belt slip determination will be described.

In step S10, the controller 10 calculates the differential thrust T based on the pulley pressure of the primary pulley 30a and the pulley pressure of the secondary pulley 30b. Furthermore, the actual shift speed AS at the differential thrust T is calculated based on the rotational speed of the primary pulley 30a and the rotational speed of the secondary pulley 30b. Note that each pulley pressure described above is calculated based on signals input from the first oil pressure sensor 55 and the second oil pressure sensor 56. Each of the above rotational speeds is calculated based on signals input from the third rotational speed sensor 52 and the fourth rotational speed sensor 53. After calculating the differential thrust T and the actual speed change AS, the process proceeds to step S11.

In step S11, the controller 10 determines whether the absolute value of the differential thrust T calculated in step S10 is greater than or equal to a predetermined value N. The predetermined value N is the absolute value of the maximum value T(N) of the differential thrust T in the region N described above. That is, in step S11, it is determined whether belt slip determination control can be performed. If the absolute value of the differential thrust T is less than the predetermined value N, the process advances to END. If the absolute value of the differential thrust T is greater than or equal to the predetermined value N, the process advances to step S12.

In step S12, the controller 10 calculates the estimated shift speed Kmax at the differential thrust T, and advances the process to step S13.

In step S13, the controller 10 determines whether the differential thrust T calculated in step S10 exceeds zero. In other words, it is determined whether the differential thrust T shifts to the Low side or to the High side. If the differential thrust T is greater than 0, the process advances to step S14. If the differential thrust T is smaller than 0, the process advances to step S16.

In step S14, the controller 10 determines whether the actual shift speed AS at the differential thrust T is greater than the estimated shift speed Kmax at the differential thrust T. In other words, it is determined whether the difference between the estimated shift speed ES corresponding to the differential thrust T and the actual shift speed AS is larger than a predetermined value. Being larger than a predetermined value means that it is larger than the value of variation in the automatic transmission 3 (the difference value between the estimated shift speed Kmax corresponding to the differential thrust T and the estimated shift speed ES corresponding to the differential thrust T). In FIG. 2, it is determined whether the actual shift speed AS at the differential thrust T exceeds the estimated shift speed Kmax (does it exceed the line segment p and reach the region A)? If it is determined in step S14 of FIG. 3 that the actual shift speed AS at the differential thrust T is greater than the estimated shift speed Kmax at the differential thrust T, the process proceeds to step S15. If it is determined in step S14 in FIG. 3 that the actual shift speed AS at the differential thrust T is not greater than the estimated shift speed Kmax at the differential thrust T, the process proceeds to END.

In step S15, the controller 10 determines that slipping of the belt 30c has occurred. If it is determined that the belt 30c is slipping, the controller 10 performs control to reduce the torque of the engine 1 or the pulley pressure of the secondary pulley 30b in order to suppress the slippage of the belt 30c.

In step S16, the controller 10 determines whether the actual shift speed AS at the differential thrust T is smaller than the estimated shift speed Kmax at the differential thrust T. In Fig. 2, this means that when the gear ratio is shifted to the High side at the differential thrust T, it is determined whether the actual gear shift speed AS exceeds the estimated gear shift speed Kmax (does it exceed line segment q and reach area B)? are doing. In other words, it is determined whether the difference between the estimated shift speed ES corresponding to the differential thrust T and the actual shift speed AS is larger than a predetermined value. Being larger than a predetermined value means that it is larger than the value of variation in the automatic transmission 3 (the difference value between the estimated shift speed Kmax corresponding to the differential thrust T and the estimated shift speed ES corresponding to the differential thrust T). If it is determined in step 16 of FIG. 3 that the actual shift speed AS at the differential thrust T is smaller than the estimated shift speed Kmax at the differential thrust T, the process proceeds to step S17. If it is determined in step S16 in FIG. 3 that the actual shift speed AS at the differential thrust T is not smaller than the estimated shift speed Kmax at the differential thrust T, the process proceeds to END.

In step S17, the controller 10 determines that the belt 30c is slipping. If it is determined that the belt 30c is slipping, the controller 10 performs control to reduce the torque of the engine 1 or the pulley pressure of the secondary pulley 30b in order to suppress the slippage of the belt 30c.

The slip determination of the belt 30c described above will be explained in chronological order with reference to FIG. 4.

FIG. 4 is a time chart showing changes in the differential thrust T between the primary pulley 30a and the secondary pulley 30b, the actual shift speed AS of the automatic transmission 3, the differential thrust characteristic coefficient, and belt slip determination. FIG. 4 shows both a case where belt slip occurs and a normal case where belt slip does not occur. In the actual shift speed AS, differential thrust characteristic coefficient, and belt slip determination, the broken line indicates the normal case, and the solid line indicates the case where belt slip occurs. The differential thrust T is shown by a solid line in both cases. Note that the actual shift speed AS and the differential thrust T shown in FIG. 4 are values within a range that can occur in the automatic transmission 3 in a normal case.

As explained above, in this embodiment, focusing on the proportional relationship between the differential thrust T and the shifting speed, the actual shifting speed AS when the predetermined differential thrust T is equal to the estimated shifting speed when the predetermined differential thrust T is If it is larger than Kmax, it is determined that belt slip has occurred. In other words, the differential thrust characteristic coefficient of the actual shifting speed AS (actual shifting speed AS/differential thrust T) is the differential thrust characteristic coefficient of the estimated shifting speed Kmax (the estimated shifting speed ES taking into account the variations in the automatic transmission 3) the threshold value. If the value exceeds the maximum value/differential thrust T), it is determined that slipping of the belt 30c has occurred. The determination is shown in FIG. 4 in chronological order.

First, a normal case where belt slip does not occur will be described. In FIG. 4, it is assumed that the differential thrust T is increased to a value E, which is the differential thrust T necessary to achieve a predetermined gear ratio. In this case, as the differential thrust T increases from time t1 to time t5, the actual speed change speed AS also increases in proportion to this. Therefore, the differential thrust characteristic coefficient of the actual shift speed AS maintains a constant value and does not exceed the differential thrust characteristic coefficient of the estimated shift speed Kmax. That is, it is not determined that belt slip has occurred. When the differential thrust T reaches the E value at time t5, the differential thrust T is maintained at the E value. Corresponding to the fact that the differential thrust force T is maintained, the actual shift speed AS also becomes a constant value.

Next, a case where belt slip occurs will be explained. Here, explanation will be given assuming that belt slip occurs at time t2. After time t1, the differential thrust T increases in order to increase the differential thrust T to the E value. The actual shift speed AS also increases in proportion to this.

When belt 30c slips at time t2, the actual shift speed AS increases rapidly after time t2. Then, the differential thrust characteristic coefficient of the actual shift speed AS also increases rapidly after time t2, and at time t3, the differential thrust characteristic coefficient of the actual shift speed AS exceeds the differential thrust characteristic coefficient of the estimated shift speed Kmax.

At time t4, when the controller 10 detects that the differential thrust characteristic coefficient of the actual shift speed AS is larger than the differential thrust characteristic coefficient of the estimated shift speed Kmax, it determines that slipping of the belt 30c has occurred.

As described above, according to the present embodiment, the differential thrust characteristic coefficient (actual variable speed AS/differential thrust T) of the actual shifting speed AS, which indicates the proportional relationship between the differential thrust T and the actual shifting speed AS, is the estimated shifting speed as the threshold value. If it is larger than the differential thrust characteristic coefficient of Kmax (maximum value of estimated shift speed ES taking into account variations in automatic transmission 3/differential thrust T), it is determined that belt 30c is slipping. As a result, even if the belt 30c slips, the belt 30c will not slip even if the gear ratio is within the range of normally available gear ratios or the gear speed is within the range of the gear change speed at the normal gear ratio. It can be determined that there is.

Next, the effects of this embodiment will be explained.

In this embodiment, the controller 10 controls the automatic transmission 3 having a primary pulley 30a, a secondary pulley 30b, and a belt 30c wound around the primary pulley 30a and the secondary pulley 30b. The controller 10 determines belt slip of the automatic transmission 3 based on the shift speed (actual shift speed AS) of the automatic transmission 3 and the differential thrust T between the primary pulley 30a and the secondary pulley 30b.

As a result, even if belt slip occurs, the belt 30c will not slip even if the gear ratio is within the range of normally available gear ratios or the gear speed is within the range of gear speeds at normal gear ratios. It can be determined that there is. Therefore, the belt slip detection performance can be improved (effects corresponding to claims 1 and 4).

Specifically, the controller 10 determines that the difference between the estimated shifting speed ES corresponding to the differential thrust T and the actual shifting speed AS is a predetermined difference (estimated shifting speed Kmax corresponding to the differential thrust T and estimated shifting speed corresponding to the differential thrust T). ES difference value), it is determined that the belt 30c is slipping.

Therefore, if the estimated shift speed ES and the actual shift speed AS deviate by more than the value of variations in the automatic transmission 3 such as sensor errors, it is determined that the belt 30c is slipping. Therefore, it is possible to prevent erroneous determination of belt slip due to variations in the automatic transmission 3, and improve the accuracy of determination of belt slip (effect corresponding to claim 3).

Further, in the present embodiment, the controller 10 calculates the shift speed (actual shift speed AS) based on the rotation speed of the primary pulley 30a and the rotation speed of the secondary pulley 30b, and calculates the shift speed (actual shift speed AS) based on the rotation speed of the primary pulley 30a and the rotation speed of the secondary pulley 30b. Calculate the differential thrust T based on the pulley pressure.

According to this configuration, belt slip is determined using oil pressure sensors (first oil pressure sensor 55, second oil pressure sensor 56) in addition to rotation speed sensors (third rotation speed sensor 52, fourth rotation speed sensor 53). . As a result, if belt slip cannot be determined by the belt slip determination method using only the rotational speed sensor (despite the belt 30c slipping, the speed change speed of the speed change ratio is within the range of the speed change speed at the normal speed change ratio). Even in the case where the belt 30c is slipping, it can be determined that the belt 30c is slipping. That is, belt slip detection performance can be improved. In addition, since the rotational speed sensor and oil pressure sensor, which are necessary components for shift control of the automatic transmission 3, are used, belt slip detection performance can be improved without providing a new sensor (without increasing cost). (Effect corresponding to claim 2).

Although the embodiments of the present invention have been described above, the above embodiments merely show a part of the application examples of the present invention, and the technical scope of the present invention is limited to the specific configuration of the above embodiments. isn't it.

3 Automatic transmission (belt continuously variable transmission)
10 Controller (control unit, control device)
30a Primary pulley 30b Secondary pulley 30c Belt

Claims (4)

A control device for a continuously variable belt transmission including a primary pulley, a secondary pulley, and a belt wound around the primary pulley and the secondary pulley,
Belt slip of the belt continuously variable transmission based on the shifting speed of the belt continuously variable transmission and the differential thrust between the primary pulley and the secondary pulley for setting the belt continuously variable transmission to the target gear ratio. comprising a control unit that determines the
The differential thrust is the thrust of the primary pulley and the secondary pulley that results in a balance thrust ratio, which is the ratio of the thrust of the primary pulley and the thrust of the secondary pulley to set the belt continuously variable transmission to the current gear ratio. It is the difference from
A control device for a continuously variable belt transmission characterized by: A control device for a continuously variable belt transmission according to claim 1,
The control unit includes:
Calculating the shifting speed based on the rotational speed of the primary pulley and the rotational speed of the secondary pulley, and calculating the differential thrust based on the pulley pressure of the primary pulley and the pulley pressure of the secondary pulley.
A control device for a continuously variable belt transmission characterized by: A control device for a continuously variable belt transmission according to claim 1 or 2,
The control unit includes:
determining that the belt is slipping when the difference between the estimated shifting speed corresponding to the differential thrust and the shifting speed is larger than a predetermined value;
A control device for a continuously variable belt transmission characterized by: A belt slip determination method for a continuously variable belt transmission having a primary pulley, a secondary pulley, and a belt wound around the primary pulley and the secondary pulley, the method comprising:
Belt slip of the belt continuously variable transmission based on the shifting speed of the belt continuously variable transmission and the differential thrust between the primary pulley and the secondary pulley for setting the belt continuously variable transmission to the target gear ratio. Determine ,
The differential thrust is the thrust of the primary pulley and the secondary pulley that results in a balance thrust ratio, which is the ratio of the thrust of the primary pulley and the thrust of the secondary pulley to set the belt continuously variable transmission to the current gear ratio. It is the difference from
A belt slip determination method for a continuously variable belt transmission, characterized in that:

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