Yamaha Hatsudoki Kabushiki Kaisha

Toshio Unno

Ryousuke Asaoka

Masaya Sakaue

Kazutoshi Ishioka

Hiroyuki Aoki

A speed change ratio controller, which controls a speed change ratio of the continuously variable transmission, normally exercises map control according to a predetermined speed change ratio map so that a V-N characteristic curve prescribed by a vehicle speed (V) and an engine rotational frequency (N) falls in a range of a predetermined region of speed change. When an accelerator opening degree exceeds a predetermined range and a vehicle load exceeds a predetermined range a target speed change ratio is corrected so that the V-N characteristic curve gets out of the predetermined region of speed change. After the V-N characteristic curve gets out of the region of speed change, the necessity of continuation of acceleration or deceleration is determined on the basis of a predetermined condition such as returning of an accelerator grip, and when the continuation is unnecessary, normal map control is automatically restored.

Controller of continuously variable transmission and vehicle provided with the same

A transmissionincludes an input shaft, an output shaft, a primary sheavethat rotates together with the input shaft, a secondary sheavethat rotates together with the output shaft, and a beltwound around both the primary sheaveand the secondary sheave. The transmissionincludes a motorthat shifts a transmission ratio by driving a movable sheaveof the primary sheave. A control device (ECU) of the transmissionincludes a secondary sheave rotation speed sensorthat detects rotation of the belt, and a control portionof the ECUperforms a sheave position control (normal control of the transmission ratio) after rotation of the beltis detected after starting.

Continuously variable transmission control device, continuously variable transmission, and vehicle equipped with the same

To place an electric motor, which composes a groove width adjustment mechanism, away from a heat source so that the electric motor can be cooled actively, and to improve both the protection and the maintainability of the electric motor. A primary sheaveand a secondary sheaveeach forming a V-groove with a variable width for receiving a belt are provided. A casefor housing the primary sheaveand the secondary sheaveis formed with an openingfor sucking and exhausting air into and out of the case. An electric motorfor driving a groove width adjustment mechanismfor the V-groove of the primary sheaveis disposed in an airflow path outside the case

V-belt continuously variable transmission for small vehicle, and straddle-type vehicle

A control system for an electronically controlled continuously variable transmission of a straddle type vehicle in which an intentional shift down operation is easily made in an AT mode. An MT mode temporarily selecting section makes the gear change mode selecting section select the MT mode temporarily and makes the gear ratio control section change the gear ratio of the transmission to a gear ratio from among a plurality of predetermined gear ratios that is positioned lower than a current gear ratio when a mode change signal is inputted in AT mode. An AT mode returning section returns the gear change mode selected by the gear change mode selecting section to AT mode when a release signal is outputted after MT mode is temporarily selected by the MT mode temporarily selecting section.

Control and transmission of straddle type vehicle, and the same

A straddle type vehicle with a control unit that improves riding comfort and controls the speed change of a continuously variable transmission electronically. Engine output is controlled by an accelerator operating part. The control unit shifts to a kick down mode where a speed change ratio is shifted to be lower than in a normal mode according to operation of a kick down switch separate from the accelerator operating part. A kick down release command is issued according to a state of the vehicle, and kick down mode is released and returned to normal mode.

Straddle type vehicle and speed change control unit of continuously variable transmission

The preferred embodiments of the present invention allow for easy shift-down and adjustment of a shift-down amount. According to some examples, a transmission () includes an electronically controlled transmission mechanism (), and a control unit () that controls the transmission mechanism (). The control unit () includes a transmission ratio control portion (), a shift mode selection portion () that can select an AT mode and that shifts to a shift-down permission mode when a shift-down permission signal () is output in the AT mode, and a shift-down operation amount computation portion () that computes a shift-down operation amount based on a vehicle state of a motorcycle (). The transmission ratio control portion () shifts down the transmission ratio of the transmission () based on the shift-down operation amount when a throttle () is operated in the shift-down permission mode.

Control device of straddle-type vehicle, transmission, and straddle-type vehicle

A straddle-type vehicle that can be accelerated rapidly by a simple operation irrespective of a selected drive mode includes a control unit that executes first control of switching between a plurality of drive modes A and B, and in each of at least two of the drive modes A and B, and second control of shifting the change gear to a kick-down state Aor Bin which the speed change ratio is lower than that of the drive mode A or B, according to operation of a shift-down operation member.

Straddle-type vehicle

A vehicle that effectively sets a gear ratio when a driver turns off a main switch during running of the vehicle includes an engine, a main switch arranged to control the engine and being operable by a driver, a continuously variable transmission arranged to transmit a drive force generated at the engine to a rear wheel, and a speed change control apparatus arranged to control a gear ratio of the continuously variable transmission and continuously control the gear ratio of the continuously variable transmission after the engine is instructed to stop due to the driver turning off the main switch.

Growing community of inventors

Shizuoka, Japan

Toshio Unno