Lighting apparatus including circuit to detect an electrical characteristic of a component of a lamp mounted in the apparatus
First Claim
Patent Images
1. A lighting apparatus comprising:
- a high pressure discharge lamp including an outer bulb, an arc tube being suspended in the outer bulb, a base being mounted on the outer bulb for detachably coupling to a socket, and an indicating element (i) located outside the arc tube and within the outer bulb, (ii) connected in parallel with the arc tube, and (iii) having a predetermined electrical characteristic for indicating a type of the high pressure discharge lamp;
a first power supply circuit electrically connected to the socket and configured for supplying a first level power to the indicating element for judging the electrical characteristic, the first level power being indicative of the electrical characteristic;
a detecting circuit (i) electrically connected to the first power supply, (ii) being responsive to the first level power, and (iii) configured to discriminate the electrical characteristic of the indicating element prior to the arc tube being illuminated; and
a second power supply circuit electrically connected to the socket and configured for supplying a second level power to the high pressure discharge lamp according to an output from the detecting circuit, wherein the second level power illuminates the arc tube.
1 Assignment
0 Petitions
Accused Products
Abstract
A lighting apparatus of the present invention includes a discharge lamp incorporating a detecting element having a predetermined electrical characteristic, a detector circuit to discriminate the electrical characteristic of the detecting element and a lighting circuit to light the discharge lamp according to the output from the detector circuit. According to the lighting apparatus of the present invention, it is possible to detect whether a discharge lamp mounted in the socket is an adapted lamp without necessity for lighting the discharge lamp.
32 Citations
12 Claims
-
1. A lighting apparatus comprising:
-
a high pressure discharge lamp including an outer bulb, an arc tube being suspended in the outer bulb, a base being mounted on the outer bulb for detachably coupling to a socket, and an indicating element (i) located outside the arc tube and within the outer bulb, (ii) connected in parallel with the arc tube, and (iii) having a predetermined electrical characteristic for indicating a type of the high pressure discharge lamp;
a first power supply circuit electrically connected to the socket and configured for supplying a first level power to the indicating element for judging the electrical characteristic, the first level power being indicative of the electrical characteristic;
a detecting circuit (i) electrically connected to the first power supply, (ii) being responsive to the first level power, and (iii) configured to discriminate the electrical characteristic of the indicating element prior to the arc tube being illuminated; and
a second power supply circuit electrically connected to the socket and configured for supplying a second level power to the high pressure discharge lamp according to an output from the detecting circuit, wherein the second level power illuminates the arc tube. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
a starting circuit configured to start the discharge lamp according to the output from the detecting circuit;
wherein the second power supply circuit stably illuminates the arc tube.
-
-
4. A lighting apparatus according to claim 3, wherein:
-
said detecting circuit comprises a judging circuit configured to judge the discharge lamp to be an adapted lamp when the output of the detecting circuit is within a specified range; and
said apparatus further comprises a controlling circuit configured to operate the starting circuit and the second power supply circuit when the discharge lamp is judged to be an adapted lamp.
-
-
5. A lighting apparatus according to claim 4, further comprising:
a controlling circuit configured to control the outputs of the starting circuit and the second power supply circuit according to he output of the detecting circuit.
-
6. A lighting apparatus according to claim 4, further comprising:
-
a timer configured to count a preset time after the judging circuit judged a mounted lamp to be an adapted lamp; and
a deactivating circuit configured to keep the starting circuit stopped during the counting by the timer.
-
-
7. A lighting apparatus according to claim 6, wherein the starting circuit includes means for applying a starting pulse to the discharge lamp.
-
8. A lighting apparatus according to claim 3, further comprising:
-
a timer configured to count a continuous time for generating starting pulses when the starting circuit generates the starting pulses; and
a deactivating circuit configured to stop the starting circuit when the time counted by the timer exceeds a preset time.
-
-
9. A lighting apparatus according to one of claims 1 to 8, wherein the indicating element has resistance or impedance value larger than a resistance or impedance value of the arc tube when the arc tube is lighted.
-
10. A lighting apparatus according to one of claims 1 to 8, further comprising:
a thermally-actuated element which is provided in the discharge lamp and is actuated according to the temperature rise when the discharge lamp is ON and turns off the power supplied to the indicating element.
-
11. A lighting apparatus according to one of claims 1 to 8, wherein the indicating element has a resistance value of temperature coefficient of resistance more than 500 ppm/°
- C.
-
12. A lighting apparatus according to claim 1, wherein said detecting circuit is operative to prevent lighting circuit from lighting the discharge lamp when the electrical characteristic of the detecting element is outside of a predetermined range.
Specification