Hitachi, Ltd.

Hitachi Maxell, Limited

Hitachi Consumer Electronics Co., Ltd.

Hideharu Saito

Takeshi Katayama

Tatsuo Morita

Hiroyuki Inoue

Masayuki Fukui

Keiichiro Tokushige

Hiroshi Maehara

Takashi Omori

Koji Hirata

Chohei Ono

Miyuki Ikeda

Hirotoshi Kemi

In order to cool the discharge lamp, cooling air generated by first and second cooling fans conveyed via first and second ducts into first and second lamp-cooling air inlets of the discharge lamp, and is blown into the discharge lamp. The first and second lamp-cooling air inlets are disposed so as to be symmetrical with respect to the optical axis of the discharge lamp, and are divided into a plurality of air inlets each having different opening surface areas. Having passes through the plurality of air inlets and diverging into a plurality of air currents, the cooling air is respectively blown to different parts of the discharge lamp. The rotational frequency of the first and second cooling fans is optimally controlled in accordance with the installation position (S) of the projector device.

Projector device

Cooling air conveyed through a cooling ductis supplied to a discharge lampvia a cooling air exithaving a plurality of flow pathstopartitioned by a partition plateAn air flow direction changeover sectionchanges a flow path through which the discharge lamp is supplied with the cooling air from the cooling air exit. An air flow blocking ballin the air flow direction changeover section moves by its own weight through a guide portionto thereby block the flow path of the cooling air exit. This allows the cooling air to be directed specifically toward an upper sidein a direction of gravity of a lamp bulb of the discharge lamp to eliminate a temperature difference, even if a mounting style of the discharge lamp is varied among desk mounting, ceiling mounting, and vertical mounting.

Lamp unit and projector employing same

In a projection image displaying device which projects imaging light emitted from a projection lens by being reflected by a projection mirror, an air inlet for sucking external air is provided at the position of a sealing mechanism of the projection mirror. Air blown off through openings provided around the projection lens is sucked into a case through this air inlet. When a cooling operation of cooling components within the case is to be performed by sealing the projection mirror, a sucking operation through the air inlet is stopped. This prevents dust in the external air from adhering to a reflective surface of the projection mirror regardless of the installation state of the projection image displaying device.

Projection image displaying device with openings around its projection lens and mirror

Cooling air conveyed through a cooling ductis supplied to a discharge lampvia a cooling air exithaving a plurality of flow pathstopartitioned by a partition plate. An air flow direction changeover sectionchanges a flow path through which the discharge lamp is supplied with the cooling air from the cooling air exit. An air flow blocking ballin the air flow direction changeover section moves by its own weight through a guide portionto thereby block the flow path of the cooling air exit. This allows the cooling air to be directed specifically toward an upper sidein a direction of gravity of a lamp bulb of the discharge lamp to eliminate a temperature difference, even if a mounting style of the discharge lamp is varied among desk mounting, ceiling mounting, and vertical mounting.

A projection display device includes: a dustproof filter that removes dust and a foreign material from drawn air; an air guide path that guides, to a liquid crystal panel, the cooling air blown by a suction fan; an air velocity detector that is arranged in the air guide path and detects the velocity of the cooling air that flows in the air guide path; and a CPU that determines, on the basis of the value detected by the air velocity detector, whether or not the dustproof filter is clogged. The air velocity detector detects the velocity of the cooling air by measuring the temperature of the air in the vicinity of the heat generating element that will be increased due to heat transfer generated by the heat generating element. This configuration improves accuracy in determining whether or not the dustproof filter is clogged.

Projection display device

A projecting apparatus cooling structure is provided in which a discharge lamp can be always kept at an appropriate temperature whether the projecting apparatus is horizontally installed on a flat surface for forward projection or for downward projection or suspended from the ceiling for forward projection or for upward projection, so that the reliability and safety of the discharge lamp is improved and so that the life of the discharge lamp can be extended. The projecting apparatus projects an image for display using a discharge lamp as a light source. The projecting apparatus includes an air inlet for taking in a cooling medium for cooling the projecting apparatus, an air outlet for exhausting the cooling medium for cooling the projecting apparatus, a plurality of fans which each let the cooling medium flow in a predetermined direction, and a control section which detects a position in which the projecting apparatus is installed, and controls the plurality of fans according to the position detected by the position sensor.

Cooling structure of projecting apparatus

Reduction of noise is achieved by devising an arrangement of heat generating parts such as a light valve element, an electric power source, a light source, etc. and an arrangement of cooling fans. In cooling the light source, the electric power source and liquid crystal panels, a cooling wind path for the liquid crystal panels and the electric power source is made separate from and independent of a cooling wind path for the light source that generates much heat, a cooling air volume is optimized for the respective cooling wind paths, and noise accompanying the rotation of the cooling fans is reduced. Also, by arranging the cooling fans substantially centrally of the respective cooling wind paths, that volume of noise, which leaks from air intake ports and air exhaust port that are opened to a housing of a unit, is reduced.

Growing community of inventors

Yokohama, Japan

Hideharu Saito