Toyota Jidosha Kabushiki Kaisha

Aisin Aw Co., Ltd.

Aisin Corporation

Yu Inase

Keisuke Ninomiya

Fumiya Kaji

Yuji Nagasawa

Junichi Tokunaga

Akira Ochi

Takayuki Miyake

Hideaki Takahara

Yuji Hattori

Wataru Ishihara

Ryo Nakamura

Kazunori Harima

Ryohei Urata

Provided is a continuously variable transmission including: a first pulley including a first fixed sheave fixed to a first rotating shaft and a first movable sheave rotating integrally with the first rotating shaft and is movable along the first rotating shaft; a second pulley including a second fixed sheave fixed to a second rotating shaft and a second movable sheave rotating integrally with the second rotating shaft and is movable along the second rotating shaft; and a transmission belt wrapped around a belt wrapping groove formed on the first pulley and around a belt wrapping groove formed on the second pulley. In a belt track for a minimum gear ratio, surfaces of the first pulley that are in contact with the transmission belt have a lower coefficient of friction relative to the transmission belt than surfaces of the second pulley that are in contact with the transmission belt.

Continuously variable transmission

Elements of a transmission belt wound around pulleys of a continuously variable transmission each include a body part, a pair of pillar parts, and a pair of side surfaces. The pair of side surfaces each include a first side surface formed on a corresponding one of the pillar parts; and a second side surface formed so as to continue from the first side surface, and located more on an inner circumference side than the first side surface. A pair of the first side surfaces each are formed so as to be inclined toward an inner side of a corresponding one of the pillar parts with respect to an extending direction, from an inner circumference side to an outer circumference side of a ring, of a corresponding one of the second side surfaces continuing from the first side surface, and a pair of the second side surfaces is formed such that the second side surfaces are spaced farther apart from each other as the second side surfaces extend from the inner circumference side to the outer circumference side, and that an angle formed between the pair of the second side surfaces is larger by 0.2 to 0.8 degrees than an opening angle of V-shaped grooves of the pulleys.

Transmission belt and continuously variable transmission, method for designing element, and method for producing element

In a transmission belt of a continuously variable transmission, a plurality of types of elements having different shapes is arrayed. A ratio of the numbers of the respective types of the elements in a string portion of the transmission belt is set so that, when first and second pulleys of the continuously variable transmission are misaligned, a total sum of deformation volumes of end portions of the elements on a side closer to a virtual plane in the element width direction is smaller than a total sum of deformation volumes of end portions of the elements on a side farther from the virtual plane. The virtual plane passes a center of a space between sheaves of the second pulley and is perpendicular to a rotating shaft of the second pulley.

A transmission belt includes: a plurality of elements, each having a plate shape, arranged sequentially in a ring manner; and a single-line ring having a belt shape and binding the elements together in a ring. Further, each of the elements includes pillar portions so that the single-line ring is inserted and a locking edge, provided on one surface in a plate thickness direction of the element, indicating a boundary region from which a plate thickness of the element changes, the pillar portions have respective ends, the ends having portions in a curved shape each having a predetermined curvature radius along a plane parallel to the single-line ring, and the portions in the curved shape include a first portion being formed on a front side at one end of the inner space, and a second portion being formed on a rear side at another end of the inner space.

Transmission belt

In an element of a power transfer belt to be wound around a primary pulley and a secondary pulley of a continuously variable transmission to transfer torque, the distance from a boundary line between a surface positioned on the outer peripheral side of the power transfer belt with respect to a rocking edge portion and the rocking edge portion to a saddle surface is determined from the slip amount due to micro slip which is relative slipping between the element and the primary pulley caused when the primary pulley pushes out the power transfer belt toward the secondary pulley, and the angular speed of the element and the angular speed of a ring in a range in which the power transfer belt is wound around the secondary pulley.

Element designing method and power transfer belt

A continuously variable transmission is configured such that a transmission ratio continuously changes by continuously changing widths of belt winding grooves of a primary pulley and a secondary pulley, and includes: the primary pulley including a first fixed sheave and a first moving sheave provided in a primary shaft; the secondary pulley including a second fixed sheave and a second moving sheave provided in a secondary shaft; a metal transmission belt wound around the primary pulley and the secondary pulley; and a moving apparatus configured to integrally move the secondary shaft and a secondary bearing supporting the secondary shaft such that a relative positional relationship between the first fixed sheave and the second fixed sheave changes.

Growing community of inventors

Susono, Japan

Yu Inase