Mitsubishi Denki Kabushiki Kaisha

Jun Imai

Hitoshi Yamazaki

Hiroshi Ito

Takao Takeda

Norihiko Tanaka

Yoshiteru Taniguchi

Minoru Uchida

Hiroshi Takada

Sadaharu Doi

Atsushi Hattori

Seiichiro Yamamoto

A process is disclosed which prepares a low pressure mercury vapor discharge lamp having a bulb and an end plate connected to the bottom of the bulb. The steps involve the application of an adhesive on one surface of the end plate, and the subsequent insertion of an exhaust tube into the end plate in such a way that an enlarged diameter portion of the exhust tube has an adhesive formed on this portion. As a result of the location and the structure of the steps, it is possible to provide a single step method of heating which functions to perform the essential bonding of all parts.

Low pressure mercury vapor discharge lamp and preparation thereof

A low pressure mercury vapor discharge lamp forms an electric discharge path by the use of a bulb placed on an end plate and the bulb is formed by a process which results in the connecting outer side surfaces of juxtaposed glass tubes through communication holes formed in the outer side surfaces respectively. The process involves placing the juxtaposed glass tubes so that their outer surfaces are opposed in a contacting state. A portion of each of the glass tubes is heated in order to form a communication hole through the utilization of a burner inserted through an open end into the interior of each of the glass tubes in order to cause fusion of that particular portion in each tube to thereby form the communication hole by wind pressure. A mass of molten glass is then forced outward at the outer peripheral edge of the communication hole whereby these outer peripheral edges of the glass tubes are mutually connected by the mass of molten glass and the open end of the tubes are then closed to form a U-shaped passage between the tubes.

Method for making low pressure mercury vapor discharge lamp

A discharge lamp having a discharge path-defining member which so defines the discharge path in the bulb that it runs in a convoluted manner with interlinked passages running between the top and the bottom of the bulb, wherein the top portion of the discharge path-defining member is provided with a top plate which permits one of the curved passage-interlinking portions at the bulb top to pass along the upper surface thereof, such that the shadow of the discharge path-defining member is eliminated from the bulb top and that the shape of the bulb can be freely selected, also enabling the lamp to be designed such that it is not easily broken, the discharge path-defining member can be easily and intimately fitted, and that the output of light is not reduced in the bulb top region.

Discharge lamp having convoluted discharge path

A phosphor suspension is prepared by adding to an aqueous solution of a polyethylene oxide, a phosphor, a phosphate or a borate of an alkali metal and a phosphor bonding agent. After having passed through a filter, the phosphor suspension flows down on the inner surface of a glass bulb of a fluorescent lamp to form a phosphor layer on it. The coated bulb is heated to a temperature which is not higher than its softening temperature while it is transported along two opposite guide rails by two endless conveyors by having both end portions supported by associated guide tips on the conveyors projecting above the guide rails.

Apparatus for manufacturing fluorescent lamps

A phosphor suspension is prepared by adding to an aqueous solution of a polyethylene oxide, a phosphor, a phosphate or a borate of an alkali metal and a phosphor bonding agent. After having passed through a filter, the phosphor suspension flows down on the inner surface of a glass bulb of a fluorescent lamp to form a phosphor layer thereon. The coated bulb is heated to a temperature which is not higher than its softening temperature while it is transported along two opposite guide rails by two endless conveyors by having both end portions supported by associated guide tips on the conveyors projecting above the guide rails.

Growing community of inventors

Hiratsuka, Japan

Jun Imai