Abstract: An optical cable includes: twisted optical fiber units each including a fiber group formed by optical fibers. At least one of the optical fiber units includes a filling that wraps an outer circumference of the fiber group.

Abstract: A heat exchanger 15 is disposed in an oil passage 14 provided in a hydraulic pressure circuit 9 of a hydraulically operated transmission, to conduct heat exchange between cooling water for an engine 2 and hydraulic fluid.

Abstract: An air heater is intended to be used in combination with an air cleaner comprising an air cleaner case, an air cleaner element dividing a space defined by the air cleaner case into a dust chamber on an upstream side with respect to the flowing direction of intake air and a clean chamber on a downstream side with respect to the flowing direction of intake air, and an intake duct connecting an air outlet pipe connected to the clean chamber to a throttle valve.

Abstract: A water passage is provided separately from an intake manifold to interconnect water jackets provided in a front bank and a rear bank of a horizontal V-type engine. An EGR valve is supported on a valve mounting seat which is provided at a front portion of the water passage. A water passageway through which cooling water flows, and a gas passageway through which an EGR gas flows, are defined in the water passage in close proximity to one another. The EGR valve is cooled by cooling wind passed through a fan opening in a radiator and by cooling water flowing through the water passageway. Thus, it is possible to avoid thermal influence on the intake manifold by the EGR valve, and to cool the EGR valve without the need for special cooling means.