Abstract: A vehicle head lamp which includes: a lamp body having a front side being opened; a lens mounted on the front side of the lamp body; a discharging lamp; a reflector being disposed within a space defined by the lamp body and the lens while supporting the discharging lamp, the reflector being tiltable with respect to the lamp body; a discharging lamp unit supplying a discharging voltage to the discharging lamp; and a connecting member. The connecting member includes, a plural number of connection cords connecting the discharging lamp and the discharging lamp unit, wherein one of the connection cords is a high voltage cord to which a high voltage is applied, a protecting tube covering the high voltage cord, and a cylindrical member being conductive and flexible wherein the cylindrical member covers the protecting tube as well as covers connection cords which are not covered with the protecting tube.

Abstract: A socket (11) for a discharge lamp bulb includes two power supply terminals, and a shielding wall for completely shielding the two power supply terminal from each other when a discharge lamp bulb is not properly seated in the socket (11). In different embodiments the socket (11) includes (FIGS. 2-5) a spring biased reciprocatably mounted cylindrical wall (24) to separate power supply terminals (21, 23), a (FIGS. 6, 7) center contact (21) mounted for reciprocation between a recessed position and an operating position in response to lamp insertion, a (FIGS. 9-14) rotary sliding member (34) or a rotary ring (40) both of which are spring biased to a blocking position and movable to a non-blocking position by lamp insertion into the socket, and a (FIGS. 16, 17) rotationally mounted member (47) having a plate (50) for separating power supply terminal segments (23b, 23c) prior to complete insertion of the lamp.

Abstract: A vehicle lamp having a discharge bulb which prevents radiation of electromagnetic waves toward the forward positions of the lamp. Radiation into the other directions is prevented by shielding members disposed around the lamp. A shade disposed in front of a discharge bulb attached to a reflector is made of metal and a stem of the shade is secured to the reflector in a state where the stem is electrically connected to a socket fixture. The shade is placed at ground potential through the fixture. Thus, the front portion of the discharge bulb is shielded and prevents radiation of the electromagnetic waves to positions in front of the lamp.

Abstract: The characteristic of a connection cord for use in a discharge lamp, such as the heat resistance, assembling easiness and adhesion facility, are intended to be improved while preventing generation of harmful gas even if heated, the connection cord also having humidity resistance. The connection cord is coated with at least two layers such that an inner sheath is made of soft resin having humidity resistance and an outer sheath is made of a rubber composition containing tetrafluoroethylene-.alpha.-olefin copolymer as the main component.

Abstract: A cord connection structure for connecting a ballast circuit and a starter circuit in which an output cord from a starter circuit unit mounted on a lamp body is connected to a discharge bulb inserted into a bulb insertion hole, and an output cord from a ballast circuit unit disposed in the vicinity of a starter circuit unit is removably connected through a connector to a connector connection part (receptacle) provided in the starter circuit unit, characterized in that a connector slip-off preventing protector covering the connector coupled into the connector connection part is provided around the connector connection part (receptacle). Such a construction makes it difficult for a general user to connect and disconnect the connector of high voltage to and from the connector connection part.

Abstract: A lighting circuit for a vehicular discharge lamp having a DC voltage booster circuit for boosting an input voltage from a DC voltage input terminal, comprises a current detector, a voltage detector, an abnormality judging circuit, and a power cutoff relay circuit. The current detector acquires a detection signal concerning an output current of the DC voltage booster circuit. The voltage detector acquires a detection signal concerning an output voltage of the DC voltage booster circuit. The abnormality judging circuit compares the levels of the detection signals from the current detector and the voltage detector with each other to determine whether or not the lighting circuit is in an abnormal status. The power cutoff circuit inhibits power supply to the discharge lamp upon reception of a signal from the abnormality judging circuit representing an abnormality in the lighting circuit.

Abstract: In a automotive headlamp having a discharge bulb as a light source, a lighting circuit receiving chamber is formed in the rear of a lamp body, a discharge bulb lighting circuit is fixed in the lighting circuit receiving chamber through resin molding, and an inner flange-like guide portion is formed in the lighting circuit receiving chamber to act as a reference member to set a liquid surface position of poured molten resin in pouring the resin. Also, the inner flange-like guide portion abuts against the surface of the molded resin portion to thereby prevent the molded resin portion from separating from the lighting circuit receiving chamber.

Abstract: A lighting circuit for a metallic halide lamp for vehicular headlight applications is disclosed. Included are a pair of input terminals between which a battery is connected for feeding the lamp via a normally open relay switch which is closed upon energization of an associated relay coil. The relay coil is connected in series with an operator actuated lamp switch and a protection switch, so that both lamp switch and protection switch must be closed to energize the relay coil and hence to close the relay switch. The protection switch is automatically opened to deenergize the relay coil when the battery develops overvoltage or when the lamp will not glow upon closure of the lamp switch. In an alternate embodiment, the protection switch is also opened in response to the development of overcurrent or overvoltage by a d.c. voltage booster circuit included in the lighting circuit.