Abstract: A heat insulating structure for an exhaust junction pipe to be disposed in an area in which exhaust gas passages having different respective lengths are merged together comprises a first heat insulation portion that covers and provides heat insulation for at least a portion of one branch part of branch parts that are branched in the exhaust junction pipe; the one branch part forms one exhaust gas passage in a not-yet-merged state of the exhaust gas passages, and forms the one exhaust gas passage having a short length.

Abstract: A heat insulating structure for an exhaust junction pipe to be disposed in an area in which exhaust gas passages having different respective lengths are merged together comprises a first heat insulation portion that covers and provides heat insulation for at least a portion of one branch part of branch parts that are branched in the exhaust junction pipe; the one branch part forms one exhaust gas passage in a not-yet-merged state of the exhaust gas passages, and forms the one exhaust gas passage having a short length.

Abstract: In an LED head, a photosensitive drum is positioned with reference to an upper surface of a circuit board on which surface at least one light-emitting element is supported in order to accurately set the distance between the light-emitting element and a photosensitive drum. Further, clips and a spring are used to accurately set the distance between the light-emitting element and a lens and to simplify the process of production.

Abstract: With the aid of a fixture, a lens holder for holding on the top surface thereof a lens array radiating outwardly a light emitted from an array of LED elements is secured to a support plate for supporting the lens holder on the top surface thereof. The fixture comprises a bottom portion having a upwardly swelling central section and serving as a leaf spring, side portions extending upward from both sides of the bottom portion, and engagement portions formed by being acutely folded and extending diagonally inward to mate with the upper side edges of the body of the LED head. The fixture is allowed to be slidably displaceable with respect to the LED head body.

Abstract: An apparatus for optically writing information comprises a row of longitudinally spaced LED array chips, a photosensitive surface arranged to face the chip row in parallel thereto, and a lens system arranged between the chip row and the photosensitive surface. Each array chip has constantly spaced LEDs to provide luminescent dots. The lens system includes convex lens elements arranged in corresponding relation to the respective array chips to form magnified images, in inverted arrangement, of the luminescent dots of the respective array chips on the photosensitive surface, so that all of the dot images on the photosensitive surface are constantly spaced.