Abstract: A compact self-ballasted fluorescent lamp has an arc tube in a double-spiral configuration, the arc tube being formed by bending a glass tube around an axis of spiral up to both ends of the glass tube, and a holder that is made of resin and holds this arc tube. Electrodes, each being equipped with a filament coil, are sealed at respective ends of the glass tube. The holder is made up of a holding resin member with a cylindrical shape having a closed bottom and a resin cover in a cone shape, the holder including a circumferential wall and an end wall that is at the edge of the circumferential wall. A heat-dissipating plate is provided inside the holding resin member, at a position corresponding to where the filament coils within the glass tube are.

Abstract: The manufacturing method comprises: a softening step of softening a straight glass tube in a heating furnace; a moving and placing step of moving the softened glass tube so that the glass tube is placed on the top of the mandrel; and a winding step of winding the glass tube placed on the top of the mandrel around the periphery of the mandrel. The mandrel is disposed beneath the glass tube starting to get soft, and the glass tube being soft is perpendicularly lowered in order to be placed on the top of the mandrel. In the winding step, the winding speed Vr at which the glass tube is wound around the mandrel is higher than the moving speed Vs at which chuck units holding the ends of the glass tube move toward the mandrel.

Abstract: A compact self-ballasted fluorescent lamp includes a double-spiral arc tube formed by winding a glass tube to its both ends around a spiral axis, and sealing electrodes each having a filament coil at the ends of the glass tube, and a holding member that has a closed bottom and holds the arc tube. The holding member has, at its end wall, insertion openings through which the ends of the glass tube are inserted. The ends of the glass tube are inserted to such positions that enable the filament coils to be positioned within the holding member, and the minimum distance L, in the insertion direction of the ends of the glass tube, between the filament coil and the edge of the insertion opening of the holding member is 6 mm.

Abstract: A compact self-ballasted fluorescent lamp includes an arc tube in which a phosphor layer is formed on an inner surface of a double spiral glass tube formed into a double spiral. The phosphor layer is formed by a process of injecting a suspension for forming the phosphor layer into the double spiral glass tube; a process of coating the inner surface of the double spiral glass tube with the suspension; a process of draining the suspension from the double spiral glass tube; a process of preliminarily drying the suspension until the suspension do longer flows according to self weight, while rotating the double spiral glass tube in a state in which a spiral axis of the double spiral glass tube is at an angle of 100 degrees with respect to a vertical axis and a turning part of the double spiral glass tube is downward; and process of completely drying the partially dried double spiral glass tube.

Abstract: Disclosed is a compact self-ballasted fluorescent lamp that includes a phosphor coating provided inside a glass tube bent to have a double-spiral configuration. The arc tube has two spiral parts that are wound around an axis “A”, and a turning part joining the two spiral parts. At any cross section of the glass tube, the applied phosphor coating is thicker in the inner surface of the glass tube near the ends of the glass tube in the axis “A” direction, than in the inner surface near the turning part.

Abstract: Disclosed is a discharge lamp with enhanced vertical illuminance and accordingly improved light distribution characteristics that is easy to manufacture and suitable for mass production. For a discharge lamp in which a discharge path with a double helix configuration is formed or a discharge lamp in which a plurality of U-shaped tubes are placed on an arc tube holder to form a single tortuous discharge path, a width of a turning part 106 is specified so as to narrow spaces formed in an arc tube top part, or swelling parts are provided in a vicinity of the arc tube top part so as to narrow the spaces.

Abstract: 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.

Abstract: A less costly bulb-shaped fluorescent lamp with improved assembly efficiency is provided which prevents the impairment of product quality due to the change in color of a holder or the slipping off of a fluorescent tube from the holder decreased in resin strength. The fluorescent lamp includes a set of fluorescent tubes, filament coils disposed at both ends of each fluorescent tube, a starter circuit for activating the fluorescent tubes, a holder for retaining the fluorescent tubes, and a case containing the starter circuit. The holder includes holes for receiving the fluorescent tubes, and a recess defined in a central portion of the holder and extended in the opposite direction of the fluorescent tubes.

Abstract: Disclosed is a discharge lamp with enhanced vertical illuminance and accordingly improved light distribution characteristics that is easy to manufacture and suitable for mass production. For a discharge lamp in which a discharge path with a double helix configuration is formed or a discharge lamp in which a plurality of U-shaped tubes are placed on an arc tube holder to form a single tortuous discharge path, a width of a turning part 106 is specified so as to narrow spaces formed in an arc tube top part, or swelling parts are provided in a vicinity of the arc tube top part so as to narrow the spaces.

Abstract: A method for producing a lamp includes forming a tubular portion that is protruded in an end of an eyelet of a base of a lamp; drawing a lead wire for supplying power out of the tubular portion; and fusing the lead wire and the tubular portion with the eyelet by plasma arc welding. This ensures that plasma arc can be discharged to the protruded tubular portion, and therefore the tubular portion and the lead wire are fused with the eyelet of the base satisfactorily and stably. In the present invention, a tubular sleeve can be used in place of the tubular portion.

Abstract: A small fluorescent discharge tube and a bulb-shaped fluorescent lamp using the same with improved rise characteristics with respect to luminous flux in the case of a relatively short non-operation time of one to six hours after a stop of operation are provided. The fluorescent discharge tube includes at least three U-shaped glass tubes joined to form one body, electrodes provided at the ends thereof, and one discharge path formed therein. The fluorescent discharge tube further includes first auxiliary amalgams in vicinities of the electrodes, main amalgams placed at least in two locations in the discharge path between the electrodes, and a second auxiliary amalgam placed at least in one location between the main amalgams.

Abstract: The present invention provides an inexpensive low-pressure mercury vapor discharge lamp having enhanced productivity. The low-pressure mercury vapor discharge lamp comprises an arc tube, a holder for holding the arc tube, a lighting circuit held on the opposite side of the holder from the arc tube and adapted for lighting the arc tube, a case having a screw portion provided at one end thereof and adapted for accommodating the lighting circuit, and a base threaded and fixed to the screw portion. A recessed groove is provided in a helical screw thread of the screw portion. The two lead wires (top lead wire and side lead wire) which are power source wires are respectively connected at one end thereof to the lighting circuit. The side lead wire is disposed along the groove and is sandwiched and fixed between the base and the screw portion.

Abstract: A fluorescent lamp in which a connecting terminals of a lighting circuit board and lead wires of a fluorescent tube easily can be connected. The lamp includes a fluorescent tube, a holder holding the fluorescent tube, a lighting circuit board provided with a lighting circuit for lighting the fluorescent tube, and a case connected to the holder and housing the lighting circuit board. At the end portion of the lighting circuit board, V-shaped or Y-shaped cut-outs, which widen toward an outer side, are formed. In the vicinity of the inner narrow portion of the cut-outs, the connecting terminals connected to the lighting circuit are provided. On a side wall formed on the holder opposite to the fluorescent tube, V-shaped or Y-shaped cut-outs, which widen as the distance from said fluorescent tube increases, are provided, and the broad portion of the cut-outs of the holder and the broad portion of the cut-outs of the lighting circuit board are arranged facing each other.

Abstract: A less costly bulb-shaped fluorescent lamp with improved assembly efficiency is provided which prevents the impairment of product quality due to the change in color of a holder or the slipping off of a fluorescent tube from the holder decreased in resin strength. The fluorescent lamp includes a set of fluorescent tubes, filament coils disposed at both ends of each fluorescent tube, a starter circuit for activating the fluorescent tubes, a holder for retaining the fluorescent tubes, and a case containing the starter circuit. The holder includes holes for receiving the fluorescent tubes, and a recess defined in a central portion of the holder and extended in the opposite direction of the fluorescent tubes.

Abstract: A less costly bulb-shaped fluorescent lamp with improved assembly efficiency is provided which prevents the impairment of product quality due to the change in color of a holder or the slipping off of a fluorescent tube from the holder decreased in resin strength. The fluorescent lamp includes a set of fluorescent tubes, filament coils disposed at both ends of each fluorescent tube, a starter circuit for activating the fluorescent tubes, a holder for retaining the fluorescent tubes, and a case containing the starter circuit. The holder includes holes for receiving the fluorescent tubes, and a recess defined in a central portion of the holder and extended in the opposite direction of the fluorescent tubes.

Abstract: An arc tube is a connected bulb composed of three U-shaped bulbs set annularly and connected by a bridge connector to include one discharge path. A reflector is set in a space enclosed by the three U-shaped bulbs, the bottom end of the reflector being fixed to a holder. The reflector has a conical part, and a cylindrical part whose height is greater than a height of a clearance between the pair of legs of each U-shaped bulb, and smaller than a height of the U-shaped bulb. At least within the height of the clearance between the pair of legs, a diameter of the reflector is greater than both a width of the clearance between the pair of legs and a width of each clearance between neighboring U-shaped bulbs, improving light distribution of the arc tube. A reflector may have a reflective body and a restrictive member integrally formed.

Abstract: A high wattage self-ballasted fluorescent lamp includes a fluorescent tube including a pair of electrodes inside, an electronic ballast circuit portion, an outer bulb, a resin case and a lamp base. (i) The outer bulb has an outer diameter of 60 mm to 70 mm, an outer diameter of a bottom portion of 50 mm to 58 mm, and a total length of 73 mm to 85 mm. (ii) The resin case has an outer diameter of 50 mm to 58 mm. (iii) The total length of the self-ballasted fluorescent lamp is not more than 148 mm. The fluorescent tube has a distance between the electrodes of 450 mm to 540 mm and an inner diameter of 8.0 mm to 10.0 mm, and is operated at a lamp current of not more than 220 mA. Thus, the self-ballasted fluorescent lamp can be compact so that the light fixture application ratio can be improved. Moreover, the self-ballasted fluorescent lamp has a lifetime as long as 6000 hours and a lamp efficiency as high as 66 lm, and the power consumption can be reduced.