Mitsuboshi Belting Ltd.

Hideo Hirai

Yasuhiro Hashimoto

Susumu Yamakawa

Norikazu Tanaka

Hiroyuki Tanaka

Kazumi Kawai

Masakatsu Ando

Naoki Fujimoto

Kyoichi Mishima

Takahide Mizuno

Takaji Nagai

Takashi Tomiyori

Tsuneo Shaura

A power transmission system having: a power transmission belt with a tensile strength such that a force of at least 17 kgf per 1 mm width is required to effect a 1% elongation of the belt; a plurality of pulleys with which the power transmission belt is operatively engaged; and an auto-tensioner having an element to engage the power transmission belt. The auto-tensioner has a damping ratio that is not greater than 20%, where the damping ratio is defined by the following formula: Damping ratio=2[(A-B)/(A+B)].times.100, where A is the force exerted by the auto-tensioner element during up-stroking of the auto-tensioner element and B is the force exerted by the auto-tensioner element during down-stroking of the idler pulley. More preferably, the damping ratio is 10-20%.

Power transmission system

An apparatus is provided for tensioning a drive belt, which apparatus consists of tensioner arm having an idler pulley thereon for engagement with the surface of a drive belt, structure for mounting the tensioner arm to a support for pivoting movement in first and second opposite directions relative to the support, and a torsion coil spring formed of wire and acting between the mounting structure and tensioner arm for biasing the tensioner arm in one of the first and second directions. The wire has a non-circular cross section.

Compact coil spring tensioner

An apparatus for tensioning a drive belt and having a tensioner arm with structure thereon for engaging a surface of the drive belt, structure for mounting the tensioner arm to a support for pivoting movement about a first axis in first and second opposite directions relative to the support including a roller bearing for guiding relative movement between the tensioner arm and support, and structure for normally biasing the belt in one of the first and second opposite directions relative to the support.

Belt tensioner

A toothed belt power transmission system having a belt tooth configuration and pulley groove configuration providing for clearances between the belt tooth root and pulley groove outer surface, and between the belt tooth tip surface and pulley groove inner surface. A power transmitting surface on a midportion of the tooth has facial engagement with a confronting sidewall surface at the midportion of the pulley groove side surface. Locations of the centers of the different arcuate surfaces of the pulley tooth and belt groove for providing the extended life, low noise operation of the drive are disclosed. A number of different constructions embodying the invention are disclosed.

Power transmission belt and drive

An apparatus for tensioning a belt consisting of a tensioner arm having an idler pulley for engagement with a surface of a drive belt, structure for mounting the tensioner arm to a suppport for pivoting movement about a pivot axis in first and second opposite directions, and structure for biasing the tensioner arm in one of the first and second directions. The mounting structure includes first and second members with first and second relatively movable cooperating friction generating surface for damping rotation of the tensioner arm. At least a portion of one of the friction generating surfaces is concave opening towards the tensioner with at least one of the friction generating surfaces having at least a portion defined by other than a radius centered on the pivot axis of the tensioner arm to thereby produce a greater resistance to rotation of the tensioner arm in the other of the first and second directions than in the one of the first and second tensioner arm pivoting directions.

Apparatus for automatically tensioning a drive belt

A belt drive having a belt provided with longitudinally spaced teeth arranged to have a preselected clearance between the side flanks thereof and the side flanks of pulley teeth with which the belt teeth are meshed in a driving operation. The clearance is caused to be a maximum at the belt tooth tips and decrease to a minimum or zero at the belt tooth roots. Different belt tooth side flank curvatures are disclosed wherein the curvatures are centered on axes located at different locations relative to the belt body. The locations of the pulley tooth flank curvature axes are related to the positions of the belt tooth flank curvature axes and a number of different relative positions thereof are disclosed.

Toothed drive belt

A variable speed pulley mounted to a torque transmission shaft having an idler structure arranged to maintain the power transmission belt centered between the pulley sheaves when the sheaves are spaced apart sufficiently to permit the belt to ride on the idler as in a stopped or idling condition of the pulley system. A tension roller may be utilized in the system for urging the belt against the outer surface of the idler, which, in the illustrated embodiment, is crowned. Structure is provided for affording facilitated adjustable movement of the adjustable sheave on the shaft, and in one embodiment, provision is made for providing lubrication therebetween.

Speed-shifting pulley with clutch mechanism

A method of manufacturing a toothed belt including the steps of providing a cylindrical mold having a plurality of longitudinal circumferentially spaced grooves, providing a thin layer of settable material on the mold surface, preforming a fabric to define a corrugated reinforcement having projections complementary to the grooves, placing the corrugated fabric in fitted association about the mold, urging the fabric forcibly against the mold to cause accurate fit of the fabric in the grooves, maintaining the urging while causing the settable material to at least partially set on the fabric corrugations, wrapping a tensile cord about the fabric-covered mold, and forming a belt body about the tensile cord and in the corrugations on the fabric. The resultant toothed belt sleeve may be cut transversely at axially spaced positions to define individual toothed drive belts, as desired. In a modified form, filler pieces are provided in the grooves of the corrugated fabric to facilitate accurate fit of the fabric to the mold.

Growing community of inventors

Kakogawa, Japan

Hideo Hirai