Bando Chemical Industries, Inc.

Bando Kagaku Kabushiki Kaisha

Masahiro Inukai

Hiroshi Matsuoka

Mitsuhiko Takahashi

Keizo Nonaka

Hiroyuki Sakanaka

Yoshiyuki Kitano

A flat belt includes a tension-resistant layer, in which a core cord is spirally wound, an upper holding rubber layer, a lower holding rubber layer, an upper rubber layer, and a lower rubber layer. The holding rubber layers and are laid on the upper and lower sides of the tension-resistant layer respectively, retaining the layer. The upper and lower rubber layers and are laid on the upper side of the upper holding rubber layer and the lower side of the lower holding rubber layer respectively. 150-300 parts by weight of ferrite for 100 parts by weight of rubber matrix are mixed in the upper rubber layer, which is on the outer peripheral side of the flat belt when the belt is wound on a guide wheel.

Flat belt

The present invention aims at improving the shock resistance of a block without lowering the power transmission property or the wear resistance of a belt while suppressing the separation of the contact portion off of the reinforcing member. A high-load drive V-belt B includes: at least one tension bandextending in an endless loop; and a plurality of blocksengaged and secured to the tension bandat a predetermined pitch in a belt length direction of the tension band, wherein the plurality of blocksare each formed by a reinforcing memberand a resin on both sides of the reinforcing memberin a belt width direction, and each include a contact portionhaving a contact surfaceto be in contact with a pulley, and a thickness w of the contact portionin a direction perpendicular to the contact surfaceis set to 1.0 mm or more and 1.8 mm or less.

High-load drive V-belt

In a heavy duty power transmission V-belt B formed by engaging tension membersandwith a plurality of blocks, . . . , to prevent as much as possible each blockfrom producing failure at the high-speed running of the belt, a fitting partof each blockhas an indentformed by upwardly recessing a portion of a resin partlocated between an upper ridgeand an innermost abutment surfaceof the fitting part. Thereby, no edge exists between the innermost abutment surfaceand the upper ridgeso that stress can be distributed. This prevents the occurrence of a crack in the resin partdue to stress concentration on the edge, the occurrence of a crack in a reinforcementof each blockbeginning at the leading end of the crack in the resin part, and in turn the fracture of an upper beamof the reinforcement, thereby providing enhanced resistance against failure of the block. Furthermore, even when a shape-retaining rubber layerof the tension memberthermally expands, the amount of expansion thereof is released into the indent. This prevents early introduction of permanent deformation of the shape-retaining rubber layerand occurrence of an excessive force in the blockdue to a compressive force produced in the fitting part, which prevents the occurrence of wobbling between the tension memberand each block. Furthermore, it can be prevented that the shape-retaining rubber layerproduces heat because of excessive deformation and in turn causes thermal expansion and thermal deterioration.

Heavy duty power transmission V-belt

A V belt for high load transmitting having at least one endless load carrier and a plurality of blocks engaged with the load carrier in the lengthwise direction of belt. The center of gravity of the block is situated near the tensile members of the load carrier. The block, in the straight running state, is so supported that it is substantially perpendicular to the load carrier. Also, the block has the surface of arcuate shape in cross section at least at a part of its side surface.

Growing community of inventors

Kobe, Japan

Masahiro Inukai