Abstract: Disclosed is an LED illumination device of a simple configuration, capable of suppressing thermal resistance to a low level, and of effectively dissipating heat generated from LED elements. Rigidity of a mounting plate is ensured by a wall of a certain height, and thereby the mounting plate now becomes possible to endure saturation vapor pressure of a coolant liquid possibly exerted thereon, and vacuum state or near-vacuum state when the coolant liquid is injected, without being deformed. Since the rigidity of the mounting plate is ensured by the wall, a wall composing a bottom face of recesses may now be thinned, and this is advantageous in view of allowing the heat generated from the LED elements to effectively conduct to the coolant liquid, and of effectively cooling the LED elements.

Abstract: Disclosed is an LED illumination device of a simple configuration, capable of suppressing thermal resistance to a low level, and of effectively dissipating heat generated from LED elements. Rigidity of a mounting plate is ensured by a wall of a certain height, and thereby the mounting plate now becomes possible to endure saturation vapor pressure of a coolant liquid possibly exerted thereon, and vacuum state or near-vacuum state when the coolant liquid is injected, without being deformed. Since the rigidity of the mounting plate is ensured by the wall, a wall composing a bottom face of recesses may now be thinned, and this is advantageous in view of allowing the heat generated from the LED elements to effectively conduct to the coolant liquid, and of effectively cooling the LED elements.

Abstract: A plug is adapted to be connected to a DC outlet to supply a DC power to the plug. The plug includes plug pins and a substantially quadrangular-shaped surrounding wall for surrounding the plug pins. The DC outlet includes: an outlet main body having an outlet unit to which the plug is adapted to be connected. The outlet unit includes a plug-receiving portion having pin-inserting holes into which the plug pins are inserted; an insertion groove formed to surround a periphery of the plug-receiving portion, the insertion groove being adapted to receive the surrounding wall; and pin-receiving pieces for being connected with the plug pins that are respectively inserted through the pin-receiving holes. Two pin-receiving holes corresponding to the pin-receiving pieces are arranged along a reference side of the plug- receiving portion and offset closer to the reference side than an opposite side to the reference side.

Abstract: A plug, adapted to be connected to a direct current (DC) outlet for supplying a DC power thereto, includes a plurality of round bar-shaped plug pins which protrudes from a front surface of a plug main body, and a surrounding wall which protrudes from the front surface of the plug main body to surround the plug pins. The plug pins are adapted to be connected the pin-receiving pieces through pin insertion holes of the DC outlet and to be supplied with power from the DC outlet. The surrounding wall is adapted to be inserted into an insertion groove of the DC outlet which is formed around the pin-insertion holes. The surrounding wall is formed in a substantially quadrangular shape, viewed from a front side thereof. The plug pins are arranged along a reference surface corresponding to one inner surface of the surrounding wall and offset closer to the reference surface than to an inner surface opposite to the reference surface.