Control device for a belt-type continuously variable transmission, control method and program for a belt-type continuously variable transmission

Abstract

To provide a better control device for a belt-type continuously variable transmission, a control method for a belt-type continuously variable transmission, and a program for such a transmission. [Solution] The control device 150 for the belt-type continuously variable transmission includes a clutch engagement determination unit 162 that determines whether or not the starting clutch is engaged, and a control unit 166 that controls the stroke position of the movable sheave of the drive pulley. When starting, the control unit 166 performs starting control by controlling the stroke position so that the movable sheave contacts the low-speed side stopper, and the clutch engagement determination unit 162 determines whether or not the starting clutch is engaged based on the engine speed, the drive wheel speed, and the first set gear ratio.

Description

Technical Field

[0006] , ,

[0001] The present disclosure relates to a control device for a belt-type continuously variable transmission, a control method for a belt-type continuously variable transmission, and a program.

Background Art

[0002] Japanese Unexamined Patent Application Publication No. 2023-151547 discloses a control device for a belt-type continuously variable transmission.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] There is a long-felt need for a better control device for a belt-type continuously variable transmission, a control method for a belt-type continuously variable transmission, and a program.

[0005] The present disclosure aims to solve the above-described problems.

Means for Solving the Problems

[0006] A first aspect of the present disclosure is a control device for a belt-type continuously variable transmission having a drive pulley connected to an engine, a driven pulley connected to a drive wheel via a starting clutch, and a belt wrapped around the drive pulley and the driven pulley, comprising: a first rotation speed acquisition unit that acquires a first rotation speed which is the rotation speed of a member located upstream of the drive pulley; a second rotation speed acquisition unit that acquires a second rotation speed which is the rotation speed of a member located downstream of the starting clutch; a engagement determination unit that determines whether or not the starting clutch is engaged; and the movable drive pulley A control device for a belt-type continuously variable transmission, comprising: a control unit for controlling the stroke position of a sheave; during starting, the control unit performs starting control to control the stroke position so that the movable sheave contacts the low-speed side stopper; and the engagement determination unit determines whether the starting clutch is engaged or not based on the first rotation speed acquired by the first rotation speed acquisition unit during the starting control, the second rotation speed acquired by the second rotation speed acquisition unit during the starting control, and a first set gear ratio which is the gear ratio when the movable sheave is in contact with the low-speed side stopper.

[0007] A second aspect of the present disclosure is a control method for a belt-type continuously variable transmission having a drive pulley connected to an engine, a driven pulley connected to a drive wheel via a starting clutch, and a belt wrapped around the drive pulley and the driven pulley, comprising: a first rotation speed acquisition step of acquiring a first rotation speed which is the rotation speed of a member located upstream of the drive pulley; a second rotation speed acquisition step of acquiring a second rotation speed which is the rotation speed of a member located downstream of the starting clutch; a engagement determination step of determining whether the starting clutch is engaged or not; and the movable seat of the drive pulley A control method for a belt-type continuously variable transmission, comprising: a control step for controlling the stroke position of the movable sheave; in the control step for starting, starting control is performed to control the stroke position so that the movable sheave contacts the low-speed side stopper; and in the engagement determination step, it is determined whether the starting clutch is engaged or not based on the first rotation speed acquired in the first rotation speed acquisition step during the starting control, the second rotation speed acquired in the second rotation speed acquisition step during the starting control, and a first set gear ratio which is the gear ratio when the movable sheave is in contact with the low-speed side stopper.

[0008] A third aspect of this disclosure is a program that causes a computer to execute the control method for a belt-type continuously variable transmission according to the second aspect. [Effects of the Invention]

[0009] This disclosure provides a better control device for a belt-type continuously variable transmission, a control method for a belt-type continuously variable transmission, and a program for such a transmission. [Brief explanation of the drawing]

[0010] [Figure 1] Figure 1 is a side view of the vehicle in the first embodiment. [Figure 2] Figure 2 is a cross-sectional view of the power unit in the first embodiment. [Figure 3] Figure 3 is a block diagram showing the configuration of the control device for a belt-type continuously variable transmission in the first embodiment. [Figure 4] Figure 4 shows the instrument cluster of the vehicle in the first embodiment. [Figure 5] Figure 5 is a flowchart of the gear shift control performed in the control device in the first embodiment. [Figure 6] Figure 6 shows the gear ratio map in the first embodiment. [Figure 7] Figure 7 shows the rate of change map in the first embodiment. [Figure 8] Figure 8 is a flowchart of the learning control performed in the control device in the first embodiment. [Modes for carrying out the invention]

[0011] In the control system for a belt-type continuously variable transmission (CVT), feedback control is performed to ensure that the transmission's gear ratio reaches the target gear ratio. To perform this feedback control, it is necessary to monitor the actual gear ratio of the CVT; therefore, the control system needs to acquire the rotational speeds of both the drive pulley and the driven pulley. For this reason, conventional belt-type CVTs were equipped with sensors to detect the rotational speed of both the drive pulley and the driven pulley.

[0012] However, there is a demand to reduce the number of sensors as much as possible from the perspective of reducing the number of parts and manufacturing costs. Belt-type continuously variable transmissions are equipped with sensors that detect the rotational speed of the drive wheels. Since the gear ratio of the final reduction gear is fixed, it is possible to determine the rotational speed of the driven pulley from the rotational speed of the drive wheels. Therefore, it is conceivable to eliminate the sensor that detects the rotational speed of the driven pulley and determine the rotational speed of the driven pulley from the rotational speed of the drive wheels detected by the sensor that detects the rotational speed of the drive wheels.

[0013] Incidentally, when a belt-type continuously variable transmission (CVT) has a starting clutch installed between the driven pulley and the drive wheel, if the starting clutch is disengaged or slipping, it is not possible to accurately determine the rotational speed of the driven pulley from the rotational speed of the drive wheel. Therefore, when the starting clutch is disengaged, feedback control of the belt-type CVT cannot be performed. For this reason, it is required to perform accurate gear shifting control of the belt-type CVT without feedback control when the starting clutch is disengaged.

[0014] Furthermore, in order to initiate feedback control of the belt-type continuously variable transmission (CVT) early, it is necessary to accurately determine whether or not the starting clutch is engaged. To determine whether or not the starting clutch is engaged, the control device needs to acquire the input rotational speed and output rotational speed of the starting clutch. If the gear ratio of the belt-type CVT is known, the input rotational speed of the starting clutch can be determined from the rotational speed of the drive pulley. However, until it is confirmed that the starting clutch is engaged, it is not possible to determine whether or not the starting clutch is engaged because the gear ratio of the belt-type CVT cannot be determined from the rotational speed of the drive pulley and the rotational speed of the driven pulley.

[0015] The control device for a belt-type continuously variable transmission (CVT) according to this disclosure can accurately control the shifting of the belt-type CVT without feedback control, even when the starting clutch is disengaged. Furthermore, the control device for a belt-type CVT according to this disclosure can determine whether or not the starting clutch is engaged, even in a belt-type CVT that does not have a sensor for detecting the rotational speed of the driven pulley.

[0016] [First Embodiment] [Vehicle configuration] FIG. 1 is a side view of a vehicle 10 according to the first embodiment. In the following description, the front, rear, upper, and lower directions are described based on the directions indicated by the arrows in FIG. 1. Also, when the user is boarding the vehicle 10 facing the front of the vehicle 10, the left side of the user is described as left, and the right side of the user is described as right.

[0017] The vehicle 10 of the first embodiment is a scooter-type motorcycle. The vehicle 10 may be a motorcycle other than the scooter type. Further, the vehicle 10 is not limited to a two-wheeled vehicle, and may be a three-wheeled vehicle, a four-wheeled vehicle, or the like.

[0018] The vehicle 10 includes a vehicle body frame 12. The vehicle body frame 12 includes a head pipe 14, a down frame 16, a lower frame 18, and a rear frame 20.

[0019] The head pipe 14 extends downward and forward. The down frame 16 extends downward and rearward from the head pipe 14. The lower frame 18 branches left and right from the lower end of the down frame 16. The lower frame 18 branched left and right extends rearward. The rear frame 20 extends upward and rearward from the rear ends of the left and right lower frames 18.

[0020] The vehicle 10 has a steering system 22. The steering system 22 includes a steering stem 24, a bottom bridge 26, a front fork 28, and a steering handle 30.

[0021] The steering stem 24 is inserted into the head pipe 14. The head pipe 14 rotatably supports the steering stem 24. The front fork 28 is connected to the lower end of the steering stem 2 through a bottom bridge 26. The front fork 28 is divided into left and right at its upper end. The front fork 28 divided into left and right extends downward and forward. A front wheel 32 is attached to the lower end of the front fork 28. The front wheel 32 is rotatably supported by both the left and right front forks 28.

[0022] A steering handle 30 is attached to the upper end of the steering stem 24. The front wheel 32 is steered by the user turning the steering handle 30. A grip 34 is attached to the left end of the steering handle 30. A throttle grip (not shown) is attached to the right end of the steering handle 30. The user can adjust the opening of the throttle valve (hereinafter referred to as throttle opening) by rotating the throttle grip.

[0023] A rear suspension 36 is attached to each of the left and right rear frames 20. The rear suspension 36 extends downward and rearward from the rear frame 20. A drive wheel 38 is attached to the tip of the rear suspension 36. The drive wheel 38 is rotatably supported by the rear suspension 36.

[0024] A power unit 42 is connected to the rear end of the lower frame 18 via a link mechanism 40. The power unit 42 includes an engine 44, a starter motor 46 (Figure 2), a belt-type continuously variable transmission 48, an air cleaner 50, and a fuel injector 52.

[0025] Engine 44 is a single-cylinder, four-stroke engine. The starter motor 46 starts the engine 44. After the engine 44 starts, the starter motor 46 acts as a generator and produces electricity.

[0026] The belt-type continuously variable transmission 48 is installed between the engine 44 and the drive wheels 38. The belt-type continuously variable transmission 48 is connected to the drive wheels 38 via a starting clutch 54 (Figure 2) and a final reduction gear 56.

[0027] The air cleaner 50 is connected to the engine 44 via the intake manifold 58. The fuel injector 52 is installed in the intake manifold 58. The fuel injector 52 injects fuel into the intake manifold 58.

[0028] A center stand 60 is provided below the power unit 42. By raising the center stand 60, the vehicle 10 can be stood upright with the drive wheels 38 lifted off the ground.

[0029] The vehicle frame 12 is covered by a vehicle cover 62 made of synthetic resin. The vehicle cover 62 includes a front cover 64, a front fender 66, a handle cover 68, a leg shield 70, a lower cover 72, side covers 74, and a rear fender 76.

[0030] The front cover 64 covers the front and rear of the head pipe 14. The front fender 66 covers the top and rear of the front wheel 32. The handle cover 68 covers the central portion of the steering handle 30 in the width direction and the steering stem 24. The leg shield 70 covers the down frame 16 and the front of the user's legs. The lower cover 72 covers the top of the lower frame 18 located on the left and right sides. The lower cover 72 has a floor step 78. The side covers 74 cover the outside of the rear frame 20 located on the left and right sides. A seat 80 is attached to the top of the side cover 74. The rear fender 76 covers the top of the drive wheel 38.

[0031] [Power unit configuration] Figure 2 is a cross-sectional view of the power unit 42 in the first embodiment. Figure 2 is a cross-sectional view taken along line II-II in Figure 1.

[0032] (Engine configuration) The engine 44 comprises a cylinder block 82, a cylinder head 84, a cylinder head cover 86, a piston 88, a connecting rod 90, a crankshaft 92, a spark plug 94, and a cam mechanism 96.

[0033] The piston 88 reciprocates within the cylinder 98 formed in the cylinder block 82. A connecting rod 90 connects the piston 88 to the crankshaft 92. The connecting rod 90 converts the reciprocating motion of the piston 88 into rotational motion, which is then transmitted to the crankshaft 92. A spark plug 94 is provided in the cylinder head 84. The spark plug 94 ignites the fuel-air mixture supplied to the combustion chamber formed by the cylinder head 84 and the piston 88. A cam mechanism 96 is provided in the cylinder head cover 86. A cam chain 102 is stretched between the camshaft 100 of the cam mechanism 96 and the crankshaft 92. The rotation of the crankshaft 92 is transmitted to the camshaft 100 by the cam chain 102. The rotation of the camshaft 100 drives intake and exhaust valves (not shown), which draw in the fuel-air mixture into the cylinder 98 and exhaust the fuel gas from the cylinder 98.

[0034] (Configuration of a belt-type continuously variable transmission) The belt-type continuously variable transmission 48 includes a drive pulley 104, a driven pulley 106, a belt 108, and a variable speed drive mechanism 110.

[0035] The drive pulley 104 is mounted on the crankshaft 92 and rotates together with the crankshaft 92. The belt 108 is stretched between the drive pulley 104 and the driven pulley 106. The belt 108 transmits the rotation of the drive pulley 104 to the driven pulley 106.

[0036] The drive pulley 104 has a fixed sheave 112 and a movable sheave 114. The fixed sheave 112 is fixed to the crankshaft 92 and rotates with the crankshaft 92. On the other hand, the movable sheave 114 is mounted on the crankshaft 92 so as to be movable in the direction of the rotation axis L1 and rotatable with the crankshaft 92.

[0037] The stroke position of the movable sheave 114 is changed by the variable speed drive mechanism 110. The variable speed drive mechanism 110 includes a motor 116 and an axis feed mechanism 118. As the motor 116 rotates, the axis feed mechanism 118 moves the movable sheave 114 in the direction of the rotation axis L1. Depending on the stroke position of the movable sheave 114, the distance between the fixed sheave 112 and the movable sheave 114 in the direction of the rotation axis L1 changes.

[0038] The driven pulley 106 has a fixed sheave 120 and a movable sheave 122. The fixed sheave 120 is rotatable relative to the output shaft 124. The movable sheave 122, on the other hand, is rotatable relative to the output shaft 124 and is also movable in the direction of the rotation axis L2. The movable sheave 122 is biased toward the fixed sheave 120 by a coil spring 126.

[0039] As the movable sheave 114 of the drive pulley 104 moves toward the fixed sheave 112, the winding diameter of the belt 108 on the drive pulley 104 increases. At this time, the winding diameter of the belt 108 on the driven pulley 106 decreases, so the force with which the belt 108 presses the movable sheave 122 of the driven pulley 106 toward the fixed sheave 120 increases. As a result, the movable sheave 122 moves toward the fixed sheave 120 against the biasing force of the coil spring 126. This reduces the ratio of the rotational speed of the drive pulley 104 to the rotational speed of the driven pulley 106 (gear ratio), resulting in a high-speed gear ratio.

[0040] When the movable sheave 114 of the drive pulley 104 moves away from the fixed sheave 112, the winding diameter of the belt 108 on the drive pulley 104 decreases. At this time, the winding diameter of the belt 108 on the driven pulley 106 increases, so the force with which the belt 108 presses the movable sheave 122 of the driven pulley 106 away from the fixed sheave 120 decreases. As a result, the movable sheave 122 moves towards the fixed sheave 120 due to the biasing force of the coil spring 126. This increases the ratio of the rotational speed of the drive pulley 104 to the rotational speed of the driven pulley 106 (gear ratio), resulting in a low gear ratio.

[0041] The crankshaft 92 is provided with a low-speed stopper 128 and a high-speed stopper 130. The low-speed stopper 128 and the high-speed stopper 130 define the range of movement of the movable sheave 114 of the drive pulley 104.

[0042] The low-speed stopper 128 is positioned in the direction of the rotation axis L1, with the movable sheave 114 sandwiched between the low-speed stopper 128 and the fixed sheave 112. When the movable sheave 114 comes into contact with the low-speed stopper 128, its movement away from the fixed sheave 112 is restricted. When the movable sheave 114 is in contact with the low-speed stopper 128, the gear ratio of the belt-type continuously variable transmission 48 becomes the lowest gear ratio.

[0043] The high-speed side stopper 130 is positioned between the movable sheave 114 and the fixed sheave 112 in the direction of the rotation axis L1. When the movable sheave 114 comes into contact with the high-speed side stopper 130, its movement toward the fixed sheave 112 is restricted. When the movable sheave 114 is in contact with the high-speed side stopper 130, the gear ratio of the belt-type continuously variable transmission 48 becomes the maximum speed gear ratio.

[0044] (Configuration of the starting clutch) The starting clutch 54 is a centrifugal clutch. The starting clutch 54 has a clutch inner 132, a clutch outer 134, and a clutch shoe 136.

[0045] The clutch inner 132 is fixed to a sleeve 138 extending from a fixed sheave 120 of the driven pulley 106 and rotates with the driven pulley 106. The clutch outer 134 is fixed to the output shaft 124 and rotates with the output shaft 124. The clutch shoe 136 is pivotably mounted to the clutch inner 132.

[0046] As the clutch inner 132 rotates together with the driven pulley 106, the clutch shoe 136 oscillates due to centrifugal force and contacts the inner surface of the clutch outer 134. When the rotational speed of the clutch inner 132 is relatively small, the clamping force of the clutch shoe 136 against the clutch outer 134 is relatively weak, resulting in a semi-clutch state where the clutch outer 134 slips against the clutch inner 132. When the rotational speed of the clutch inner 132 is relatively large, the clamping force of the clutch shoe 136 against the clutch outer 134 becomes relatively strong, resulting in a fully engaged state where the clutch outer 134 rotates together with the clutch inner 132. The starting clutch 54 is not limited to a shoe clutch; it may also be a multi-plate clutch.

[0047] (Configuration of the final deceleration gear) The final reduction gear 56 includes an idler gear 140, an idler shaft 142, a final gear 146, and a drive shaft 148.

[0048] The idler gear 140 is fixed to the idler shaft 142 and rotates together with the idler shaft 142. The idler gear 140 meshes with a gear formed on the output shaft 124 and transmits the rotation of the output shaft 124 to the idler gear 140.

[0049] The final gear 146 is fixed to the drive shaft 148 and rotates together with the drive shaft 148. The final gear 146 meshes with a gear formed on the idler shaft 142 and transmits the rotation of the idler shaft 142 to the drive shaft 148.

[0050] A drive wheel 38 is attached to the drive shaft 148, and the drive shaft 148 drives the drive wheel 38.

[0051] [Control device configuration] Figure 3 is a block diagram showing the configuration of the control device 150 for the belt-type continuously variable transmission 48 in the first embodiment. The control device 150 performs gear shifting control for the belt-type continuously variable transmission 48.

[0052] The control device 150 comprises a calculation unit 152 and a storage unit 154. The calculation unit 152 is a processor such as a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit). The calculation unit 152 includes a first rotational speed acquisition unit 156, a second rotational speed acquisition unit 158, a gear ratio acquisition unit 160, a engagement determination unit 162, a learning unit 164, a control unit 166, and a notification control unit 168. The first rotational speed acquisition unit 156, the second rotational speed acquisition unit 158, the gear ratio acquisition unit 160, the engagement determination unit 162, the learning unit 164, the control unit 166, and the notification control unit 168 are realized by the execution of a program stored in the storage unit 154 in the calculation unit 152. At least a portion of the first rotational speed acquisition unit 156, the second rotational speed acquisition unit 158, the gear ratio acquisition unit 160, the engagement determination unit 162, the learning unit 164, the control unit 166, and the notification control unit 168 may be implemented by an integrated circuit such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field-Programmable Gate Array). At least a portion of the first rotational speed acquisition unit 156, the second rotational speed acquisition unit 158, the gear ratio acquisition unit 160, the engagement determination unit 162, the learning unit 164, the control unit 166, and the notification control unit 168 may be implemented by an electronic circuit including discrete devices.

[0053] The storage unit 154 is a computer-readable, non-transient, tangible storage medium. The storage unit 154 is composed of volatile memory (not shown) and non-volatile memory (not shown). The volatile memory is, for example, RAM (Random Access Memory). The non-volatile memory is, for example, ROM (Read Only Memory), flash memory, etc. Data is stored in the volatile memory, for example. Programs, tables, maps, etc. are stored in the non-volatile memory, for example. At least a portion of the storage unit 154 may be provided in the processor, integrated circuit, etc. mentioned above. At least a portion of the storage unit 154 may be mounted on equipment connected to the vehicle 10 by a network. The storage unit 154 has a gear ratio map 170 and a fluctuation rate map 172.

[0054] The first rotational speed acquisition unit 156 acquires the engine rotational speed (first rotational speed) from the engine rotational speed sensor 174. The engine rotational speed sensor 174 detects the rotational speed of the crankshaft 92 and outputs the rotational speed of the crankshaft 92 as the engine rotational speed. The crankshaft 92 corresponds to the component located upstream of the drive pulley 104.

[0055] The second rotation speed acquisition unit 158 ​​acquires the drive wheel rotation speed (second rotation speed) from the drive wheel rotation speed sensor 176. The drive wheel rotation speed sensor 176 detects the rotation speed of the drive shaft 148 and outputs the rotation speed of the drive shaft 148 as the drive wheel rotation speed. The drive shaft 148 corresponds to the component located downstream of the driven pulley 106.

[0056] The gear ratio acquisition unit 160 acquires the gear ratio of the belt-type continuously variable transmission 48. The gear ratio of the belt-type continuously variable transmission 48 is the ratio of the rotational speed of the drive pulley 104 to the rotational speed of the driven pulley 106. If the gear ratio of the belt-type continuously variable transmission 48 is R, the rotational speed of the drive pulley 104 is Ndr, and the rotational speed of the driven pulley 106 is Ndn, then the gear ratio R can be calculated using the following formula. R = Ndr / Ndn

[0057] Since the drive pulley 104 rotates together with the crankshaft 92, the engine speed is used as the rotational speed of the drive pulley 104. When the starting clutch 54 is engaged, the driven pulley 106 rotates together with the output shaft 124. Also, the gear ratio of the final reduction gear 56 is fixed. Therefore, the rotational speed of the driven pulley 106 can be determined from the gear ratio of the final reduction gear 56 and the rotational speed of the drive wheels when the starting clutch 54 is engaged.

[0058] The belt-type continuously variable transmission 48 of the first embodiment is not equipped with a sensor that directly detects the rotational speed of the driven pulley 106. Therefore, when the starting clutch 54 is not engaged, the rotational speed of the driven pulley 106 differs from the rotational speed of the output shaft 124, and the gear ratio acquisition unit 160 cannot acquire the gear ratio of the belt-type continuously variable transmission 48.

[0059] The engagement determination unit 162 determines whether the starting clutch 54 is engaged or not. If the difference in rotational speed between the input rotational speed and the output rotational speed of the starting clutch 54 is less than a predetermined difference in rotational speed, the engagement determination unit 162 determines that the starting clutch 54 is engaged. If the difference in rotational speed between the input rotational speed and the output rotational speed of the starting clutch 54 is greater than or equal to a predetermined difference in rotational speed, the engagement determination unit 162 determines that the starting clutch 54 is not engaged.

[0060] The input rotational speed for the starting clutch 54 refers to the rotational speed of the clutch inner 132 of the starting clutch 54. Since the clutch inner 132 rotates together with the driven pulley 106, the rotational speed of the clutch inner 132 can be determined from the engine speed and the gear ratio of the belt-type continuously variable transmission 48.

[0061] The output rotational speed of the starting clutch 54 refers to the rotational speed of the clutch outer 134 of the starting clutch 54. Since the clutch outer 134 rotates together with the output shaft 124, the rotational speed of the clutch outer 134 can be determined from the rotational speed of the drive wheels and the gear ratio of the final reduction gear 56. The input and output rotational speeds of the starting clutch 54 will be described in detail later.

[0062] The learning unit 164 learns the minimum speed gear ratio (first set gear ratio). The minimum speed gear ratio is the gear ratio of the belt-type continuously variable transmission 48 when the movable sheave 114 of the drive pulley 104 is in contact with the low-speed stopper 128. The learning of the minimum speed gear ratio will be described in detail later.

[0063] The control unit 166 controls the gear shifting of the belt-type continuously variable transmission 48. The control unit 166 controls the stroke position of the movable sheave 114 to achieve the target gear ratio. The target gear ratio is set based on the gear ratio map 170 according to the throttle opening detected by the throttle opening sensor 178 and the vehicle speed. The stroke position of the movable sheave 114 is changed by the gear shift drive mechanism 110. The gear shifting control will be described in detail later.

[0064] The notification control unit 168 controls the notification unit 180. Figure 4 shows the meter 182 of the vehicle 10 in the first embodiment. The notification unit 180 is a lamp provided within the meter 182 that indicates vehicle speed, engine speed, etc. The user is notified when the notification unit 180 lights up. The notification unit 180 may also notify the user through displays other than the lighting of the lamp. The notification unit 180 may also be a buzzer, speaker, etc. In that case, the user is notified by outputting sound or the like from the notification unit 180.

[0065] If the difference between the design gear ratio, which is the design value of the gear ratio of the belt-type continuously variable transmission 48 when the movable sheave 114 of the drive pulley 104 contacts the low-speed side stopper 128, and the minimum speed gear ratio after learning is greater than or equal to a predetermined value, the notification control unit 168 controls the notification unit 180 to notify the user.

[0066] [Regarding gear shift control] When the starting clutch 54 is engaged, the gear ratio acquisition unit 160 can acquire the gear ratio of the belt-type continuously variable transmission 48. In this case, the control unit 166 performs feedback control so that the gear ratio of the belt-type continuously variable transmission 48 acquired by the gear ratio acquisition unit 160 becomes the target gear ratio.

[0067] On the other hand, if the starting clutch 54 is not engaged, the gear ratio acquisition unit 160 cannot acquire the gear ratio of the belt-type continuously variable transmission 48. In this case, the control unit 166 performs starting control by controlling the stroke position of the movable sheave 114 of the drive pulley 104 so that the movable sheave 114 contacts the low-speed side stopper 128.

[0068] Figure 5 is a flowchart of the gear shift control performed in the control device 150 in the first embodiment. The gear shift control is performed repeatedly at a predetermined cycle.

[0069] In step S1, the engagement determination unit 162 determines whether the starting clutch 54 is engaged or not. If it is determined that the starting clutch 54 is engaged (step S1: YES), the process proceeds to step S2. If it is determined that the starting clutch 54 is not engaged (step S1: NO), the process proceeds to step S3.

[0070] In step S2, the control unit 166 performs feedback control to control the stroke position of the movable sheave 114 of the drive pulley 104 using the gear ratio acquired by the gear ratio acquisition unit 160. After that, the gear control is terminated.

[0071] Figure 6 shows the gear ratio map 170 in the first embodiment. Based on the gear ratio map 170, a target gear ratio is set according to the throttle opening and vehicle speed. As shown in the gear ratio map 170 in Figure 6, the target gear ratio changes according to the vehicle speed and throttle opening. Note that the gear ratio map 170 in Figure 6 is shown as a graph relating engine speed and vehicle speed. In order to obtain the target gear ratio of the belt-type continuously variable transmission 48, it is necessary to convert using the gear ratio of the final reduction unit 56. Through feedback control, the stroke position of the movable sheave 114 is adjusted so that the gear ratio of the belt-type continuously variable transmission 48 becomes the target gear ratio.

[0072] In step S3, the control unit 166 performs starting control. After that, the gear shift control is terminated. During starting control, the control unit 166 controls the stroke position of the movable sheave 114 of the drive pulley 104 so that the movable sheave 114 comes into contact with the low-speed stopper 128. This allows for accurate gear shift control of the belt-type continuously variable transmission 48 even without feedback control.

[0073] [Regarding the input / output rotation speed of the starting clutch] The engagement of the starting clutch 54 is determined based on the input rotational speed and output rotational speed of the starting clutch 54.

[0074] As mentioned above, the input rotational speed for the starting clutch 54 can be determined from the engine speed and the gear ratio of the belt-type continuously variable transmission 48.

[0075] When the starting clutch 54 is not engaged, the gear ratio acquisition unit 160 cannot acquire the gear ratio of the belt-type continuously variable transmission 48. However, during starting control, the movable sheave 114 of the drive pulley 104 is in contact with the low-speed side stopper 128, and the gear ratio of the belt-type continuously variable transmission 48 is fixed to the lowest speed gear ratio. Therefore, in the control device 150 of the first embodiment, the engagement determination unit 162 makes an engagement determination of the starting clutch 54 when the control unit 166 is performing starting control. As a result, the engagement determination unit 162 can determine the input rotational speed of the starting clutch 54 using the lowest speed gear ratio.

[0076] The gear ratio of the belt-type continuously variable transmission 48 also changes due to the deformation of the belt 108. As the throttle opening increases and the engine output torque increases, the deformation of the belt 108 increases. As a result, the gear ratio of the belt-type continuously variable transmission 48 increases and shifts towards the lower gear ratio. Therefore, in the control device 150 of the first embodiment, the fastening determination unit 162 corrects the minimum gear ratio by the fluctuation rate. Figure 7 is a diagram showing the fluctuation rate map 172 in the first embodiment. As shown in the fluctuation rate map 172 of Figure 7, the fluctuation rate is set according to the throttle opening. This fluctuation rate indicates the rate of change in the gear ratio of the belt-type continuously variable transmission 48 due to the deformation of the belt 108.

[0077] If the input rotational speed of the starting clutch 54 is Nin, the engine speed is Ne, the minimum gear ratio is Rl, and the rate of change is D, then the input rotational speed Nin can be calculated using the following formula. Nin = Ne / (D·Rl)

[0078] As mentioned above, the output rotational speed of the starting clutch 54 can be determined from the rotational speed of the drive wheels and the gear ratio of the final reduction gear 56. If the output rotational speed of the starting clutch 54 is Nout, the rotational speed of the drive wheels is Nr, and the gear ratio of the final reduction gear 56 is Rf, then the output rotational speed Nout can be calculated using the following formula. Nout = Nr × Rf

[0079] [Regarding learning the minimum gear ratio] The lowest gear ratio is affected primarily by the following factors (a) to (c). (a) Dimensional variation of belt-type continuously variable transmissions (b) Deterioration (wear and tear) of the belt over time (c) Belt deformation due to load fluctuations

[0080] In the control device 150 of the first embodiment, the learning unit 164 learns the minimum gear ratio while driving. The learning unit 164 determines the minimum gear ratio that has changed due to the factors (a) and (b) above. Learning of the minimum gear ratio is performed when the learning mode is set. The learning mode may be set periodically or according to the total mileage of the vehicle 10.

[0081] In learning mode, the gear shift control performed by the control device 150 differs in some respects from normal gear shift control. In normal gear shift control, if it is determined that the starting clutch 54 is not engaged, the control unit 166 performs starting control, and if it is determined that the starting clutch 54 is engaged, the control unit 166 performs feedback control.

[0082] On the other hand, in learning mode, even if it is determined that the starting clutch 54 is engaged, if the throttle is off (throttle opening is 0 degrees) and the drive wheel rotation speed is 1 or higher than the first predetermined rotation speed, the control unit 166 does not perform feedback control. In this case, the control unit 166 controls the stroke position of the movable sheave 114 of the drive pulley 104 so that the movable sheave 114 contacts the high-speed side stopper 130.

[0083] Furthermore, in learning mode, even if it is determined that the starting clutch 54 is engaged, the control unit 166 continues starting control if the rotational speed of the drive wheels is less than the second predetermined rotational speed. The second predetermined rotational speed is set to a rotational speed lower than the first predetermined rotational speed.

[0084] Figure 8 is a flowchart of the learning control performed in the control device 150 in the first embodiment. The learning control is performed at predetermined intervals during the period in which the learning mode is set.

[0085] In step S11, the learning unit 164 determines whether or not starting control is in progress. If it is determined that starting control is in progress (step S11: YES), the process proceeds to step S15. If it is determined that starting control is not in progress (step S11: NO), the process proceeds to step S12.

[0086] In step S12, the learning unit 164 determines whether the throttle is off or not. If it is determined that the throttle is off (step S12: YES), the process proceeds to step S13. If it is determined that the throttle is on (step S12: NO), the learning control is terminated.

[0087] In step S13, the learning unit 164 determines whether the drive wheel rotation speed is equal to or greater than a first predetermined rotation speed. If it is determined that the drive wheel rotation speed is equal to or greater than the first predetermined rotation speed (step S13: YES), the process proceeds to step S14. If it is determined that the drive wheel rotation speed is less than the first predetermined rotation speed (step S13: NO), the learning control is terminated.

[0088] In step S14, the learning unit 164 learns the minimum speed gear ratio based on the gear ratios and maximum speed gear ratios of the belt-type continuously variable transmission 48 acquired by the gear ratio acquisition unit 160. After that, the learning control is terminated.

[0089] The learning unit 164 calculates a correction coefficient from the maximum speed gear ratio (second setting gear ratio), which is the design value of the gear ratio of the belt-type continuously variable transmission 48 when the movable sheave 114 of the drive pulley 104 contacts the high-speed side stopper 130, and the gear ratio of the belt-type continuously variable transmission 48 acquired by the gear ratio acquisition unit 160. If the maximum speed gear ratio is Rh, the gear ratio of the belt-type continuously variable transmission 48 is Rs, and the correction coefficient is C, then the correction coefficient C can be calculated using the following formula. C = Rs / Rh

[0090] The learning unit 164 calculates the corrected minimum gear ratio by multiplying the minimum gear ratio by a correction coefficient. If the minimum gear ratio before correction is R1 and the minimum gear ratio after correction is Rl', then the corrected minimum gear ratio Rl' can be calculated using the following formula. Rl'=C·Rl

[0091] This makes it possible to compensate for variations in the minimum gear ratio caused by dimensional variations in the belt-type continuously variable transmission 48 and the aging deterioration of the belt 108.

[0092] In step S15, which is performed when it is determined that launch control is in progress (step S11: YES), the learning unit 164 determines whether the throttle is on or off. If it is determined that the throttle is on (step S15: YES), the process proceeds to step S16. If it is determined that the throttle is off (step S15: NO), the learning control is terminated.

[0093] In step S16, the learning unit 164 determines whether the starting clutch 54 is engaged or not. The determination of whether the starting clutch 54 is engaged is made using the determination result of the engagement determination unit 162. If it is determined that the starting clutch 54 is engaged (step S16: YES), the process proceeds to step S17. If it is determined that the starting clutch 54 is not engaged (step S16: NO), the learning control is terminated.

[0094] In step S17, the learning unit 164 learns the minimum speed gear ratio based on the gear ratio of the belt-type continuously variable transmission 48 acquired by the gear ratio acquisition unit 160 and the fluctuation rate obtained from the fluctuation rate map 172. After that, the learning control is terminated. If the corrected minimum speed gear ratio is Rl', the gear ratio of the belt-type continuously variable transmission 48 is Rs, and the fluctuation rate is D, then the corrected minimum speed gear ratio R1' can be calculated using the following formula. Rl'=Rs / D

[0095] This allows the gear ratio acquisition unit 160 to remove the fluctuation in the gear ratio due to deformation of the belt 108 from the gear ratio of the belt-type continuously variable transmission 48, thereby correcting for fluctuations in the minimum gear ratio caused by dimensional variations in the belt-type continuously variable transmission 48 and the aging deterioration of the belt 108.

[0096] [Second Embodiment] In the first embodiment, learning control was performed while the vehicle 10 was in motion. In contrast, in the second embodiment, learning control is performed while the vehicle 10 is stationary. The learning control in the second embodiment is performed as initial learning of the minimum gear ratio during the final inspection of the vehicle 10, etc.

[0097] Learning control is performed with the center stand 60 raised and the drive wheels 38 in a free-spinning state. During learning control, the control unit 166 performs starting control by controlling the stroke position of the movable sheave 114 of the drive pulley 104 so that the movable sheave 114 contacts the low-speed stopper 128.

[0098] The learning unit 164 learns the gear ratio acquired by the gear ratio acquisition unit 160 as the minimum gear ratio when the drive wheel rotation speed is equal to or greater than the third predetermined rotation speed. The third predetermined rotation speed is set to the rotation speed at which the starting clutch 54 is engaged. When the drive wheel 38 is free-spinning, there is virtually no deformation of the belt 108, so it is not necessary to consider the rate of change as in the learning control in the first embodiment.

[0099] The following additional information is disclosed regarding the above embodiments.

[0100] (Note 1) The control device for a belt-type continuously variable transmission of the present disclosure is a control device (150) for a belt-type continuously variable transmission (48) having a drive pulley (104) connected to an engine (44), a driven pulley (106) connected to a drive wheel (38) via a starting clutch (54), and a belt (108) wrapped around the drive pulley and the driven pulley, the control device (150) comprising: a first rotation speed acquisition unit (156) that acquires a first rotation speed which is the rotation speed of a member located upstream of the drive pulley; a second rotation speed acquisition unit (158) that acquires a second rotation speed which is the rotation speed of a member located downstream of the starting clutch; and a determination of whether the starting clutch is engaged or not. The system includes a fastening determination unit (162) that determines whether or not the starting clutch is engaged, and a control unit (166) that controls the stroke position of the movable sheave (114) of the drive pulley. At the time of starting, the control unit performs starting control by controlling the stroke position so that the movable sheave contacts the low-speed side stopper (128). The fastening determination unit determines whether or not the starting clutch is engaged based on the first rotation speed acquired by the first rotation speed acquisition unit at the time of the starting control, the second rotation speed acquired by the second rotation speed acquisition unit at the time of the starting control, and a first set gear ratio which is the gear ratio when the movable sheave is in contact with the low-speed side stopper. This makes it possible to determine whether or not the starting clutch is engaged even in a belt-type continuously variable transmission that does not have a sensor to detect the rotation speed of the driven pulley.

[0101] (Note 2) In the control device for a belt-type continuously variable transmission described in Appendix 1, during the starting control, the engagement determination unit may determine the input rotational speed of the starting clutch based on the first rotational speed acquired by the first rotational speed acquisition unit and the first set gear ratio, and determine the output rotational speed of the starting clutch based on the second rotational speed acquired by the second rotational speed acquisition unit, and determine that the starting clutch is engaged if the difference in rotational speed between the input rotational speed and the output rotational speed is smaller than a predetermined difference in rotational speed. This makes it possible to determine whether or not the starting clutch is engaged even in a belt-type continuously variable transmission that does not have a sensor to detect the rotational speed of the driven pulley.

[0102] (Note 3) In the control device for a belt-type continuously variable transmission described in Appendix 1 or 2, the control device further includes a gear ratio acquisition unit (160) that acquires a gear ratio determined from the first rotational speed acquired by the first rotational speed acquisition unit and the second rotational speed acquired by the second rotational speed acquisition unit, and when the engagement determination unit determines that the starting clutch is in an engaged state, the control unit may perform feedback control to control the stroke position based on the gear ratio acquired by the gear ratio acquisition unit. This enables accurate gear control of the belt-type continuously variable transmission.

[0103] (Note 4) The control device for the belt-type continuously variable transmission described in Appendix 1 further comprises: a gear ratio acquisition unit that acquires a gear ratio determined from the first rotational speed acquired by the first rotational speed acquisition unit and the second rotational speed acquired by the second rotational speed acquisition unit; and a learning unit (164) that learns the first set gear ratio according to the gear ratio acquired by the gear ratio acquisition unit when the second rotational speed acquired by the second rotational speed acquisition unit is equal to or greater than a first predetermined rotational speed and the throttle is off, and a second set gear ratio which is the gear ratio when the movable sheave is in contact with the high-speed side stopper (130). The control unit may control the stroke position so that the movable sheave comes into contact with the high-speed side stopper when the second rotational speed acquired by the second rotational speed acquisition unit is equal to or greater than a first predetermined rotational speed and the throttle is off. This makes it possible to determine the first set gear ratio with high accuracy.

[0104] (Note 5) The control device for the belt-type continuously variable transmission described in Appendix 1 further comprises: a gear ratio acquisition unit that acquires a gear ratio determined from the first rotational speed acquired by the first rotational speed acquisition unit and the second rotational speed acquired by the second rotational speed acquisition unit; a storage unit (154) that stores a map showing the rate of change of the gear ratio according to the throttle opening; and a learning unit that learns the first set gear ratio according to the gear ratio acquired by the gear ratio acquisition unit and the rate of change according to the throttle opening acquired from the map when the starting control is in progress, the engagement determination unit determines that the starting clutch is engaged, and the throttle is on; and when the engagement determination unit determines that the starting clutch is engaged, and the second rotational speed acquired by the second rotational speed acquisition unit is less than a second predetermined rotational speed, the control unit may continue the starting control. This makes it possible to determine the first set gear ratio with high accuracy.

[0105] (Note 6) The control device for the belt-type continuously variable transmission described in Appendix 1 further comprises a gear ratio acquisition unit that acquires a gear ratio determined from the first rotational speed acquired by the first rotational speed acquisition unit and the second rotational speed acquired by the second rotational speed acquisition unit, and further comprises a learning unit that learns the gear ratio acquired by the gear ratio acquisition unit as the first set gear ratio when the drive wheels are in a free-spinning state, the starting control is in progress, and the second rotational speed is equal to or greater than a third predetermined rotational speed, and when the learning unit is learning the first set gear ratio, the control unit may perform the starting control. This makes it possible to determine the first set gear ratio with high accuracy.

[0106] (Note 7) In the control device for a belt-type continuously variable transmission described in any one of appendices 4 to 6, a notification control unit (168) may be further provided that controls the notification unit (180) to notify the user if the difference between the design gear ratio, which is the design value of the gear ratio when the movable sheave is in contact with the low-speed side stopper, and the first set gear ratio after learning is greater than or equal to a predetermined value. This allows the user to be notified if the first set gear ratio of the belt-type continuously variable transmission deviates from the design value.

[0107] (Note 8) In the control device for a belt-type continuously variable transmission described in Appendix 7, the notification unit may notify the user by at least one of a display and / or sound.

[0108] (Note 9) The control method for a belt-type continuously variable transmission according to the present disclosure is a control method for a belt-type continuously variable transmission having a drive pulley connected to an engine, a driven pulley connected to a drive wheel via a starting clutch, and a belt wrapped around the drive pulley and the driven pulley, comprising: a first rotation speed acquisition step of acquiring a first rotation speed which is the rotation speed of a member located upstream of the drive pulley; a second rotation speed acquisition step of acquiring a second rotation speed which is the rotation speed of a member located downstream of the starting clutch; and a engagement determination step of determining whether or not the starting clutch is engaged. The system includes a control step for controlling the stroke position of the movable sheave of the drive pulley, wherein in the control step for starting, starting control is performed to control the stroke position so that the movable sheave contacts the low-speed side stopper, and in the engagement determination step, it is determined whether the starting clutch is engaged or not based on the first rotation speed acquired in the first rotation speed acquisition step during the starting control, the second rotation speed acquired in the second rotation speed acquisition step during the starting control, and a first set gear ratio which is the gear ratio when the movable sheave is in contact with the low-speed side stopper. This makes it possible to determine whether the starting clutch is engaged or not even in a belt-type continuously variable transmission that does not have a sensor for detecting the rotation speed of the driven pulley.

[0109] (Note 10) The program of this disclosure causes a computer to execute the control method for a belt-type continuously variable transmission described in Appendix 9. This makes it possible to determine whether or not the starting clutch is engaged, even in a belt-type continuously variable transmission that does not have a sensor to detect the rotational speed of the driven pulley.

[0110] While this disclosure has been described in detail, it is not limited to the individual embodiments described above. These embodiments can be added, replaced, modified, partially deleted, etc., in any way that does not depart from the gist of this disclosure or from the intent of this disclosure derived from the claims and their equivalents. These embodiments can also be implemented in combination. For example, the order of operations and processes in the embodiments described above are given as examples only and are not limited thereto. The same applies when numerical values ​​or mathematical formulas are used in the description of the embodiments described above. [Explanation of symbols]

[0111] 38...Drive wheels 44...Engine 48... Belt-type continuously variable transmission 54... Starting clutch 104...Drive pulley 106...Driven pulley 108...Belt 114...Movable sheave 128...Low-speed stopper 130...High-speed stopper 150...Control device 154...Memory unit 156...First rotation speed acquisition unit 158...Second rotation speed acquisition unit 160...Gear ratio acquisition unit 162...Fastening determination unit 164...Learning Unit 166...Control Unit 168... Notification Control Unit 180... Notification Department

Claims

1. The drive pulley connected to the engine, A driven pulley connected to the drive wheel via a starting clutch, A belt wrapped around the drive pulley and the driven pulley, A control device for a belt-type continuously variable transmission, A first rotation speed acquisition unit acquires a first rotation speed, which is the rotation speed of a component located upstream of the drive pulley. A second rotation speed acquisition unit acquires a second rotation speed, which is the rotation speed of a component located downstream of the aforementioned starting clutch. A clutch engagement determination unit that determines whether or not the starting clutch is engaged, A control unit that controls the stroke position of the movable sheave of the drive pulley, Equipped with, During starting, the control unit performs starting control, controlling the stroke position so that the movable sheave contacts the low-speed stopper. The fastening determination unit determines whether the starting clutch is in a fastened state based on the first rotation speed acquired by the first rotation speed acquisition unit during the starting control, the second rotation speed acquired by the second rotation speed acquisition unit during the starting control, and the first set gear ratio, which is the gear ratio when the movable sheave is in contact with the low-speed side stopper, as a control device for a belt-type continuously variable transmission.

2. In the control device for a belt-type continuously variable transmission according to claim 1, During the aforementioned starting control, the fastening determination unit will Based on the first rotational speed acquired by the first rotational speed acquisition unit and the first set gear ratio, the input rotational speed of the starting clutch is determined. Based on the second rotational speed acquired by the second rotational speed acquisition unit, the output rotational speed of the starting clutch is determined. A control device for a belt-type continuously variable transmission, which determines that the starting clutch is engaged when the difference in rotational speed between the input rotational speed and the output rotational speed is smaller than a predetermined difference in rotational speed.

3. In the control device for a belt-type continuously variable transmission according to claim 1 or 2, The system further includes a gear ratio acquisition unit that acquires a gear ratio determined from the first rotational speed acquired by the first rotational speed acquisition unit and the second rotational speed acquired by the second rotational speed acquisition unit, A control device for a belt-type continuously variable transmission, wherein when the engagement determination unit determines that the starting clutch is in an engaged state, the control unit performs feedback control to control the stroke position based on the gear ratio acquired by the gear ratio acquisition unit.

4. In the control device for a belt-type continuously variable transmission according to claim 1, A gear ratio acquisition unit that acquires a gear ratio determined from the first rotational speed acquired by the first rotational speed acquisition unit and the second rotational speed acquired by the second rotational speed acquisition unit, A learning unit learns the first set gear ratio in accordance with the gear ratio acquired by the gear ratio acquisition unit when the second rotation speed acquired by the second rotation speed acquisition unit is equal to or greater than the first predetermined rotation speed and the throttle is off, and the second set gear ratio which is the gear ratio when the movable sheave is in contact with the high-speed side stopper. Furthermore, A control device for a belt-type continuously variable transmission, wherein, when the second rotational speed acquired by the second rotational speed acquisition unit is equal to or greater than the first predetermined rotational speed and the throttle is off, the control unit controls the stroke position so that the movable sheave contacts the high-speed side stopper.

5. In the control device for a belt-type continuously variable transmission according to claim 1, A gear ratio acquisition unit that acquires a gear ratio determined from the first rotational speed acquired by the first rotational speed acquisition unit and the second rotational speed acquired by the second rotational speed acquisition unit, A memory unit that stores a map showing the rate of change of the gear ratio according to the throttle opening, A learning unit learns the first set gear ratio in accordance with the gear ratio acquired by the gear ratio acquisition unit and the fluctuation rate corresponding to the throttle opening acquired from the map, when the starting control is in progress, the starting clutch is determined to be in a engaged state by the engagement determination unit, and the throttle is on. Furthermore, A control device for a belt-type continuously variable transmission, wherein if the engagement determination unit determines that the starting clutch is engaged, and the second rotational speed obtained by the second rotational speed acquisition unit is less than a second predetermined rotational speed, the control unit continues the starting control.

6. In the control device for a belt-type continuously variable transmission according to claim 1, The system further includes a gear ratio acquisition unit that acquires a gear ratio determined from the first rotational speed acquired by the first rotational speed acquisition unit and the second rotational speed acquired by the second rotational speed acquisition unit, The system further includes a learning unit that learns the gear ratio acquired by the gear ratio acquisition unit as the first set gear ratio when the drive wheel is in a free-spinning state, the starting control is in progress, and the second rotational speed is equal to or greater than the third predetermined rotational speed. When the learning unit has learned the first set gear ratio, the control unit is a control device for a belt-type continuously variable transmission that performs the starting control.

7. In the control device for a belt-type continuously variable transmission according to any one of claims 4 to 6, A control device for a belt-type continuously variable transmission, further comprising a notification control unit that controls a notification unit to notify the user when the difference between the design gear ratio, which is the design value of the gear ratio when the movable sheave is in contact with the low-speed side stopper, and the first set gear ratio after learning is greater than or equal to a predetermined value.

8. In the control device for a belt-type continuously variable transmission according to claim 7, The notification unit is a control device for a belt-type continuously variable transmission that notifies the user by at least one of a display and / or sound.

9. The drive pulley connected to the engine, A driven pulley connected to the drive wheel via a starting clutch, A belt wrapped around the drive pulley and the driven pulley, A control method for a belt-type continuously variable transmission having, A first rotation speed acquisition step is to acquire a first rotation speed, which is the rotation speed of a component located upstream of the drive pulley. A second rotation speed acquisition step is to acquire a second rotation speed, which is the rotation speed of a component located downstream of the aforementioned starting clutch. A engagement determination step to determine whether the starting clutch is in an engaged state, A control step for controlling the stroke position of the movable sheave of the drive pulley, It has, In the control step during starting, starting control is performed to control the stroke position so that the movable sheave contacts the low-speed stopper. A control method for a belt-type continuously variable transmission, wherein in the engagement determination step, it is determined whether or not the starting clutch is engaged based on the first rotational speed acquired in the first rotational speed acquisition step during the starting control, the second rotational speed acquired in the second rotational speed acquisition step during the starting control, and the first set gear ratio, which is the gear ratio when the movable sheave is in contact with the low-speed side stopper.

10. A program that causes a computer to execute the control method for a belt-type continuously variable transmission described in claim 9.

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