Matsushita Electric Industrial Co., Ltd.

Matsushita Electronics Corporation

Panasonic Corporation

Matushita Electric Industrial Co., Ltd.

Matsushita Electronics Corporation and Matsushita Electric Works, Ltd.

Kenji Itaya

Shiro Iida

Takeshi Matsumura

Akiko Nakanishi

Yoshinori Kakuno

Yasushige Tomiyoshi

Kenji Nakano

Toshiaki Kurachi

Akira Takahashi

Tatsuhiro Yabuki

Junichi Takahashi

Shogo Takahashi

Tamotsu Ando

Nobuharu Hata

Kouichi Katase

Koichi Katase

Takeshi Arakawa

Yuji Tsuneto

Kohhei Iwase

Katsushi Seki

Koji Miyazaki

Hiroki Kitagawa

Noriyuki Uchida

Kouji Miyazaki

Hiroki Nakagawa

Akio Kitada

Kenichiro Takahashi

Tetsuya Tahara

Kiyoshi Hashimotodani

Mitsuharu Kawasaki

Toyokazu Amano

Yoji Tashiro

Kohei Iwase

Masao Yukawa

Seidou Tani

A manufacturing method of a double spiral glass tube having a bump that is difficult to break. The manufacturing method includes the steps of: causing the bump forming section () in the central portion () to have greater tube thickness than the other sections in the glass tube () that has been deformed into a double spiral shape; heating and softening part of the bump forming section; and forming a bump () by injecting a nitrogen gas () into the inner space of the glass tube from both ends thereof to expand the bump forming section. With this structure, the bump forming section is preliminarily formed to have a greater tube thickness than the other sections. As a result, the bump, which is formed by expanding the bump forming section to have a smaller tube thickness than before the expansion, still maintains a sufficient strength.

Process for producing double helical glass tube, light-emitting tube for fluorescent lamp, and fluorescent lamp

Fluorescent lamp

An arc tube is formed by turning a glass tube at a substantially middle thereof and winding the glass tube from the middle to its both ends around an axis to form a double spiral, and sealing electrodes at both ends of the glass tube. The spiral pitch of a spiral part in a vicinity of one of the ends and an adjacent spiral part in the direction of the axis is set larger than the spiral pitch of other adjacent spiral parts, to widen a gap between the one end and the adjacent spiral part.

Arc tube with shortened total length, manufacturing method for arc tube, and low-pressure mercury lamp

An arc tube includes an arc tube body and a pair of electrodes. The arc tube body is formed from a glass tube which is double-spirally wound from a middle portion to both ends around a spiral axis. The pair of electrodes are sealed at both ends of the arc tube body. Mercury is enclosed in the arc tube substantially in a single form. Each of the electrodes includes a multiple-coiled filament which is wound substantially one turn in a last coiling stage.

Arc tube and low-pressure mercury lamp that can be reduced in size

Base for fluorescent lamp

An arc tube is formed by a glass tube that is turned at a substantially middle thereof and wound around a spiral axis from the middle, to have a double-spiral structure. End portions of the arc tub are wound around the spiral axis. A holder has insertion openings formed therein in such shapes that correspond to shapes of the ends of the arc tube. The insertion openings allow the ends of the arc tube to be inserted along a bottom wall of the holder. The holder also includes guide grooves provided in the areas before the insertion openings in the spiral direction of the ends of the arc tube. The guide grooves allow the end portions of the arc tube to come in contact, and when the arc tube is rotated around the axis, guide the ends of the arc tube to the insertion openings.

Low-pressure mercury lamp having a spiral arc tube and method for assembling the same

A connection wireextends from an end of an induction coilalong a surface of a base portionof a bobbinwhich surface is located close to a luminous bulbThe connection wireis separated from a sealing portionof an inner tubeand an outertube

Bulb type electrodeless fluorescent lamp

A bulb-type fluorescent lamp has a case having an open end portion for housing a lighting circuit therein, an arc tube extending outside through the open end portion of the case, and a globe having an open end portion for housing the arc tube therein. An adhesive is supplied to the inner surface of the open end portion of the case at four circumferentially spaced areas, and the open end portion of the globe is inserted into the open end portion of the case. As a result, the globe is fixed to the case with the adhesive.

Low-pressure mercury vapor discharge lamp with improved heat dissipation, and manufacturing method therefore

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Takatsuki, Japan

Kenji Itaya