Bridgestone Corporation

Sony Corporation

Bridestone Corporation

Takashi Mizusawa

Kenji Tateishi

Shingo Sugihara

Shoko Nagamoto

Hideo Nagasaka

Katsuyuki Akutsu

Yuji Ikegami

Yusuke Kajio

Kazutatsu Tokuyama

Hideo Nagasaki

Tozaburo Nishimura

Daisuke Tsukuda

Shinsuke Hiraoka

Eiji Ishihara

Mitsuharu Isoda

In some embodiments, a head mounted display is provided, comprising a light guide, at least first and second diffraction gratings, alignment marks Aand Bassociated with the first diffraction grating, and alignment marks Aand Bassociated with the second diffraction grating. The first diffraction grating may be disposed on a first surface of the light guide, the first surface facing away from a light input. The second diffraction grating may be disposed on a second surface of the light guide, the second surface facing towards the light input. The second diffraction grating may be adapted to diffract at least some of the light input into the light guide, and the first diffraction grating may be adapted to diffract at least some light transmitted through the light guide back into the light guide.

Optical device, head mounted display, assembling method for the same, holographic diffraction grating, display device, and alignment device

A crawler includes a crawler main body (a rubber crawler main body ()), a tensile body (), guide protrusions (), and flat surfaces (). The tensile body () is provided with a flat portion () that is arranged along a width direction of the crawler main body and a slanting portion () that is slanted and arranged at a width direction outer side of the crawler main body relative to the flat portion (). The guide protrusions () are formed at an inner peripheral face of the crawler main body at a width direction middle portion of the crawler main body. The flat surfaces () are formed at the width direction outer sides of the crawler main body relative to the guide protrusions (). Turning wheels (a driving wheel (), an idling wheel () and rolling wheels ()) provided at a vehicle roll on the flat surfaces (). In a linear region of the crawler main body as seen in a side view of the crawler main body, if a thickness from an imaginary plane projected from the flat portion () in the width direction of the crawler main body to an end edge at a crawler main body width direction outer side of the slanting portion () is represented by L, then a result of subtracting a turning direction length of the crawler main body at the flat portion () from a turning direction length of the crawler main body at the slanting portion () is less than 2&#x3c0;L.

Crawler

An elastic crawler and an elastic crawler drive mechanism collectively suppress the interference between the pin members and the engaging portions, and improve the durability of the engaging portions. The elastic crawler includes on an inner circumferential side thereof a plurality of engaging portions () respectively engageable with a plurality of pin members () arranged at a spacing in a circumferential direction of a sprocket, wherein: the engaging portions () have a pressure receiving surface () which receives the pin members (), an outline shape in side view of the pressure receiving surface () being formed by an envelope Ldrawn by an outer end of the pin members () when the sprocket rolls coaxially with a central axis of a virtual rotor with a rolling diameter Ddefined by D=(pitch of the engaging portions)&#xd7;(number of pin members)/(&#x3c0;)&#xd7;a, and 0.9&#x2264;a&#x2264;1, together with the virtual rotor on a plane.

Elastic crawler and elastic crawler drive mechanism

A crawler includes crawler body formed by an elastic body shaped into an endless loop, a tensile body embedded in the crawler body and wound around a circumferential direction of the crawler body, guide projections formed at an inner circumferential surface of a width direction central portion of the crawler body and spaced apart in the circumferential direction of the crawler body, a flat face, upon which a rotating wheel provided at a vehicle rolls, forming an inner circumferential surface further toward a width direction outer side of the crawler body than the guide projections and an inclined face, upon which the rotating wheel rolls, inclined from an outer side end portion of the flat face in a crawler body width direction such that a thickness of the crawler body gradually increases toward the width direction outer side and circumferential inner side of the crawler body.

A sprocket () is capable of engaging with engaging portions () on an elastic endless belt (). On a tooth face (F) of a tooth () of the sprocket (), a portion of a tooth base on at least one side of a center line (O) of the tooth () is a tooth base surface (), and the tooth base surface () is inclined relative to the center line (O) of the tooth () at an angle (A) in a range of 0&#xb0; or greater to 7.5&#xb0; or less so as to approach the center line (O) of the tooth () towards a tooth tip surface ().

Sprocket and elastic crawler drive mechanism

In an elastic crawler () and an elastic crawler drive mechanism (), at least a portion of the outer edge of an engaging portion () has a cross-sectional arc shape such that both the trajectory drawn by the outer edge of the engaging portion () from when the engaging portion () starts to enter a tooth groove of a sprocket () until engagement between the engaging portion () and teeth () is complete and the trajectory drawn by the outer edge of the engaging portion () from when the engaging portion () starts to disengage from the teeth () until disengagement is complete do not project further outward than the outer edge of the engaging portion () when the engagement is complete.

This disclosure is to provide an elastic crawler drive mechanism including an elastic crawler () with engaging portions () disposed on an endless belt (), and a sprocket () having teeth (), wherein: engaging surfaces (F) of the engaging portions () have flat engaging planes () in contact with a part of tooth surfaces (F) of the sprocket () when in contact with tooth bottom surfaces () of the sprocket (), and when the engaging portions () are in contact with the tooth bottom surfaces (), and simultaneously the engaging planes () are in contact with the tooth surfaces (F) of the sprocket (), at least one of the tooth surfaces (F) of the sprocket () and the engaging planes () of the engaging portions () form gaps (C) between the tooth surfaces (F) and the engaging planes (), on sides closer to the tooth bottom surfaces () than contact portions (P) of the tooth surfaces (F) and the engaging planes ().

Elastic crawler drive mechanism

A main cord layer is embedded in a crawler main body, and a first bias cord layer, a second bias cord layer, a third bias cord layer and a fourth bias cord layer are embedded at an outer peripheral side of the main cord layer. Bias cords of the second bias cord layer and bias cords of the third bias cord layer are inclined in a direction that is opposite, with respect to a crawler circumferential direction, bias cords of the fourth bias cord layer that are inclined with respect to the crawler circumferential direction.

Rubber crawler

An elastic crawler includes an endless elastic body; cores that each include a core body and a pair of protrusions; lugs, on the outer circumferential side of the elastic body, each disposed so as to avoid a crawler circumferential direction area corresponding to at least a portion of the core in the crawler circumferential direction; and grooves, on the crawler inner circumferential surface, each positioned outward in the crawler width direction from the pair of protrusions in a crawler circumferential direction area corresponding to the core, each of the grooves being recessed relative to crawler inner circumferential surface portions adjacent to the groove on both sides in the crawler circumferential direction.

Elastic crawler

A rubber crawler includes a rubber belt, a main cord layer that is incorporated within the rubber belt and includes a main cord extending around the crawler circumferential direction, a bias cord layer that is incorporated further to the crawler circumferential outside than the main cord layer and is configured from bias cords extending at an angle with respect to the crawler circumferential direction, a bias cord layer that is interposed between the bias cord layer and the main cord layer, and is configured from bias cords extending at an angle with respect to the crawler circumferential direction so as to intersect the first bias cords, and a reinforcement cord layer that is interposed between the bias cord layer and the bias cord layer, and is configured from reinforcement cords extending in the crawler width direction.

A rubber crawler includes a rubber belt, a main cord layer that is incorporated within the rubber belt and includes a main cord configured from plural twisted strands covered with rubber, the main cord extending around the crawler circumferential direction, and a bias cord layer incorporated within the rubber belt at the crawler circumferential outside of the main cord layer configured by at least one bias ply and configured from at least one bias ply that is formed from a plurality of bias cords extending at an angle with respect to the crawler circumferential direction, disposed side-by-side around the crawler circumferential direction and covered in rubber such that bias cords of the bias ply at the circumferential outermost side of the crawler are, as viewed from the crawler circumferential outside, angled toward an opposite side, with respect to the crawler circumferential direction, from the angled side of the strands.

Providing a crawler core member that can be coupled in a simple operation without employing dedicated coupling components, and that can suppress deformation due to input from a road surface. Coupling can be achieved by a simple operation without employing dedicated coupling components, and deformation due to input from a road surface can be suppressed in a crawler core memberthat configures an endless crawler beltwhen plural of the core members are disposed at uniform intervals along a peripheral direction S and the peripheral direction adjacent core membersare coupled together. The core memberincludes a pin portionextending in the width direction, a hooking grooveintegrally formed to the pin portionand hooking onto the pin portionof an adjacent core member, and a pair of wing portionsintegrally formed to the pin portionand respectively disposed at both width direction sides of the pin portion, extending towards the width direction outsides.

Growing community of inventors

Yokohama, Japan

Takashi Mizusawa