Easily-assembled compact self-ballasted fluorescent lamp
First Claim
1. A compact self-ballasted fluorescent lamp, comprising:
- an arc tube formed by a glass tube double-spirally wound from a middle to both ends thereof around a predetermined axis; and
a cylindrical holding member having an end wall where a pair of insertion openings are formed, and holding the arc tube in a state where both end parts of the glass tube are inserted in the insertion openings, wherein a pitch of (a) each end part and (b) an adjacent spiral part in a direction of the axis is larger than a pitch of other adjacent spiral parts, to widen a gap between each end part and the adjacent spiral part, and a minimum distance between (a) a first area that is on an outer surface of a spiral part adjacent to one of the ends in the direction of the axis and (b) a second area that is on a surface of the end wall and that faces the first area, is in a range of 1.5 to 4.0 mm inclusive.
2 Assignments
0 Petitions
Accused Products
Abstract
A compact self-ballasted fluorescent lamp includes an arc tube formed by a glass tube double-spirally wound from its middle to both ends around a spiral axis, and a cylindrical holding member having a closed bottom and holding the arc tube, a case fit to cover a circumferential wall of the holding member, and the like. End-vicinity parts of the glass tube are formed to have a larger gap with glass tube parts adjacent in the direction of the spiral axis. The arc tube is held in a state where the distance L1 between a first point that is on an outer surface of a glass tube part adjacent to one of the ends of the glass tube in the direction of the spiral axis and a second point on a surface of the end wall facing the first point is about 1.5 mm.
-
Citations
15 Claims
-
1. A compact self-ballasted fluorescent lamp, comprising:
-
an arc tube formed by a glass tube double-spirally wound from a middle to both ends thereof around a predetermined axis; and
a cylindrical holding member having an end wall where a pair of insertion openings are formed, and holding the arc tube in a state where both end parts of the glass tube are inserted in the insertion openings, wherein a pitch of (a) each end part and (b) an adjacent spiral part in a direction of the axis is larger than a pitch of other adjacent spiral parts, to widen a gap between each end part and the adjacent spiral part, and a minimum distance between (a) a first area that is on an outer surface of a spiral part adjacent to one of the ends in the direction of the axis and (b) a second area that is on a surface of the end wall and that faces the first area, is in a range of 1.5 to 4.0 mm inclusive. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. A compact self-ballasted fluorescent lamp, comprising:
-
an arc tube formed by a glass tube double-spirally wound from a middle to both ends thereof around a predetermined axis; and
a cylindrical holding member having an end wall on which a pair of tube-holding structures are provided for holding the arc tube in a state where both end parts of the glass tube are inserted in and held by the tube-holding structures, wherein a pitch of (a) each end part and (b) an adjacent spiral part in a direction of the axis is larger than a pitch of other adjacent spiral parts, to widen a gap between each end part and the adjacent spiral part, and a distance between (a) a first point that is at a middle of an area sandwiched between the pair of tube-holding structures in a circumferential direction of the end wall as viewed in the direction of the axis and (b) a second point that is on an outer surface of a spiral part positioned outward with respect to the holding member and facing the first point, is in a range of 1.5 to 4.0 mm inclusive. - View Dependent Claims (9, 10, 11, 12, 13, 14, 15)
-
Specification