JP4124532B2 - Single-end mold high pressure discharge lamp - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a single-ended high pressure discharge lamp according to the preamble of claim 1 of the appended claims.
[0002]
[Prior art]
Such a high-pressure discharge lamp is disclosed, for example, in EP 0 867 911. The high-pressure discharge lamp described therein has a base composed of a base shell and an inner part of the base, and the base shell and the inner part of the base are each made of an electrically insulating plastic and are fixed to each other by two metal parts. Yes. The high-pressure discharge lamp further has a double-end sealed arc tube having a base side end, a counter-base side end, and a tubular extension, and the tubular extension is formed integrally with the base side end. The arc tube is surrounded by an outer tube fused thereto and having a tubular extension. The tubular extension of the outer tube surrounds the tubular extension of the arc tube at a distance. The structural unit consisting of the arc tube and the outer tube is fixed by a bulb tubular extension in a recess in the inner part of the base that fits closely to the tubular extension of the outer tube. An electrode disposed inside the arc tube and used to generate a gas discharge is powered by two leads. The base-side lead extends through the tubular extension of the arc tube, and the counter-base-side lead is connected to a lead that returns to the base. The lead returning to the base is partly surrounded by a ceramic tube and fixed at one end in another recess of the base.
[0003]
[Problems to be solved by the invention]
An object of the present invention is to make a single-piece high-pressure discharge lamp having a high-voltage resistance and a receiving device with an improved lamp tube.
[0004]
[Means for Solving the Problems]
This object is based on the present invention, wherein the receiving device is formed integrally with the base and is located between the tubular extension of the arc tube and the tubular extension of the outer tube, and contacts the inner surface of the tubular extension of the outer tube. It is solved by having a color. Particularly advantageous embodiments of the invention are described in the respective dependent claims.
[0005]
A single-piece high-pressure discharge lamp according to the present invention has a double-end sealed arc tube in which a tubular extension is integrally formed at the end of the base and an electrode for generating a luminescent gas discharge is disposed therein. ing. Each of these electrodes is conductively connected to a lead derived from the arc tube. The arc tube is surrounded by an outer tube secured to it and having a tubular extension. The tubular extension of the outer tube surrounds the tubular extension of the arc tube at a distance. The base of the high-pressure discharge lamp according to the invention has a receiving device for the tubular extension of the outer tube. In accordance with the present invention, a collar that is integrally formed with the base and is located between the tubular extension of the arc tube and the tubular extension of the outer tube and is in contact with the inner surface of the tubular extension of the outer tube is disposed on the receiving device. ing. This collar ensures that the structural unit consisting of the arc tube and the outer tube is centered within the lamp cap. Furthermore, the collar made of an electrically insulating material improves the electrical insulation of the base-side lead extending in the tubular extension of the arc tube, thereby increasing the high voltage resistance of the base. In order to further improve the electrical insulation of the base-side lead, it is advantageous that the collar additionally contacts the outer surface of the arc tube tubular extension.
[0006]
It is advantageous if the receiving device comprises an annular recess that is used as a depth stop for the tubular extension of the outer tube. Thereby, the built-in depth of the lamp tube can be adjusted reproducibly. The base of the high-pressure discharge lamp according to the invention preferably consists of a base shell and a base inner part fixed therein by a metal part, the receiving device for the tubular extension of the outer tube being preferably in the base inner part. Is arranged. By this measure, the lamp tube in which the electrodes are arranged can be adjusted with respect to the reference plane defined by the base.
[0007]
Furthermore, the base of the high-pressure discharge lamp according to the present invention is preferably provided with another receiving device connected to the lead on the opposite side and fixed to the lead returning to the base. The lead returning to the base is preferably partially surrounded by a ceramic tube for the purpose of electrical insulation. More preferably, the part of the return lead surrounded by the ceramic tube is provided on the separate receiving device so that the electrical insulation of the return lead is further improved by the insulating material of the inner part of the base surrounding it. Is placed inside.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
The invention will now be described in detail with reference to the preferred embodiments illustrated in the drawings.
[0009]
The advantageous embodiment shown is a single-piece high pressure discharge lamp which is considered for use in automotive headlamps. This lamp has a tubular arc tube 100 having a discharge chamber 103 which is hermetically closed, a cap side collapsing end portion 101 and a counter cap side crushing end portion 102. Two electrodes 104 and 105 rush into the discharge chamber 103. These electrodes 104 and 105 are electrically conductive through molybdenum foils 106 and 107 that are hermetically embedded in the crushing end portions 101 to 102 in leads 108 and 109 led from the crushing end portions 101 to 102, respectively. It is connected. The lamp base has a base shell 110 made of a plastic injection-molded product and an adjustable base inner part 111 arranged inside the base shell 110 and also made of a plastic injection-molded product. The base shell 110 has two electrical contact pieces 112 and 113 at the end opposite to the arc tube 100. Among them, the central contact piece 112 is electrically connected to the lead 108 led out from the base side crushing end portion 101, and another annular electric contact piece 113 is connected to the anti-base side via the lead 115 surrounded by the ceramic tube 114. The lead 109 that is led out from the crushing end 102 is electrically connected.
[0010]
The arc tube 100 is surrounded by a cylindrical outer tube 116 disposed substantially coaxially with the arc tube 100. The outer tube 116 is fused to the tubular extension 118 of the arc tube 100 extending into the anti-clamp side crush end 102 and the cap shell 110. The outer tube 116 includes a tubular extension 119 that partially surrounds the tubular extension 118 of the arc tube 100. In order to attach the base to the high-pressure discharge lamp, the tubular extension 119 of the outer tube 116 is integrated with the inner part 111 of the base in a receiving device formed as a recess of the inner part 111 of the outer tube 116. The metal sleeve 120 surrounding the extension 119 is sealed by being heated by high frequency induction heating so that the plastic 127 located between the metal sleeve 120 and the tubular extension 119 is melted. . The receiving device for the base inner part 111 has an annular collar 125 formed integrally with the base inner part 111. The collar 125 is in contact with the inner surface of the tubular extension 119 of the outer tube 116 and the outer surface of the tubular extension 118 of the arc tube 100. The collar 125 together with the base inner part 111 forms an annular recess used as a depth stop for the tubular extension 119 of the outer tube 116 in the area of the receiving device.
[0011]
The base shell 110 is formed in a pot shape. The base inner part 111 is completely disposed in the interior 117 of the base shell 110. The outer wall of the base inner part 111 is formed by an annular metal part 121 that is fixed to the base inner part 111 and partially surrounds the base inner part 111. A metal ring 122 is embedded in the side wall of the pot-shaped cap shell 110, and four welding tongues 123 are integrally formed on the metal ring 122. Each of these four welding tongues 123 penetrates into the interior 117 of the base shell 110, and when the base inner part 111 is fitted into the base shell 110 and subsequently during the adjustment of the lamp, Elastically contacts the metal part 121. After the adjustment is completed, the welding tongue 123 is welded to the annular metal part 121, whereby the base inner part 111 and the base shell 110 are coupled to each other at the adjusted position. In order to allow the welding tool to approach the welding tongue 123, the wall of the base shell 110 has a through opening 124 in the range of the welding tongue 123.
[0012]
In the figure, one of the four welding tongues 123 is shown in broken lines because it is usually covered with an annular metal part 121 on the surface selected here. The annular metal part 121 and the metal sleeve 120 define an annular groove in the base inner part 111, and a coil (not shown) is temporarily installed in the annular groove to heat the metal sleeve 120 by high frequency induction. Inset. The welding tongue 123 is formed by bending from the metal ring 122 and enters the inside 117 of the base shell 110. The side wall of the pot-shaped base shell 110 has a through opening 124 in the range of the welding tongue piece 123.
[0013]
The base inner part 111 further has another receiving device formed as a through opening for the lead 115. A part of the lead 115 surrounded by the ceramic tube 114 is arranged in the receiving device, so that the insulating material of the inner part 111 of the base is made better with respect to another metal part placed in the base. Insulate electrically.
[Brief description of the drawings]
FIG. 1 is a partial cross-sectional side view of a single-ended high pressure discharge lamp in an advantageous embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 100 Light-emitting tube 101 Cushion side crushing end part 102 Opposite side crushing end part 103 Discharge chamber 104 Electrode 105 Electrode 108 Lead 109 Lead 110 Cap | shell inner part 111 Outer pipe | tube inner part 116 Outer tube tubular extension part 119 Outer tube tubular extension 119 Part 121 Metal ring part 122 Metal ring 123 Welding tongue 125 Color

Claims (8)

A double-end sealed arc tube (100) comprising a base-side end (101), an anti-base-side end (102), and a tubular extension (118) integrally formed with the base-side end (101); At least two electrodes (104, 105) for generating a gas discharge of the arc tube (100) fixed to the arc tube (100) and at least partially surrounding the arc tube (100), and a tubular extension of the arc tube (100) ( 118) with an outer tube (116) having a tubular extension (119) surrounding at a distance, a first base electrical contact piece (112) and a second base electrical contact piece (113). An arc tube that is made of an electrically insulating material and has a receiving device to which a tubular extension (119) of the outer tube is fixed, and is derived from the end portion (101) of the cap side of the arc tube (100). Extending within the tubular extension (118) of the first A base electrode lead (108) for conductively connecting the electrode (105) to the first base electric contact piece (112), and a second electrode derived from the non-base end (102) of the arc tube (100) The lead-side lead (104) electrically connected to the second base electrical contact piece (113) via the lead (115) extending outside the outer pipe (116) and returning to the base (110, 111). 109), the receiving device is formed integrally with the base (110, 111), the tubular extension (118) of the arc tube (100) and the tubular extension of the outer tube (116). A single-ended high-pressure discharge lamp having a collar (125) positioned between (119) and in contact with the inner surface of the tubular extension (119) of the outer tube. The single-ended high-pressure discharge lamp according to claim 1, wherein the collar (125) is in contact with the outer surface of the tubular extension (118) of the arc tube (100). 2. A single-ended high pressure discharge lamp as claimed in claim 1, characterized in that the receiving device has an annular recess used as a depth stop for the tubular extension (119) of the outer tube (116). The base (110, 111) has a base shell (110) made of an electrically insulating material and a base inner part (111) made of an electrically insulating material, and the base inner part (111) is made of metal parts (121, 122, 123). The single-piece high-pressure discharge lamp according to claim 1, wherein the single-piece high-pressure discharge lamp is fixed to the cap shell (110). The single-piece high-pressure discharge lamp according to claim 3, wherein the receiving device is arranged in the inner part (111) of the base. The single-piece high-pressure discharge lamp according to claim 1, wherein the die (110, 111) has a receiving device for the lead (115). A single-piece high pressure discharge lamp according to claim 6, characterized in that the lead (115) is at least partially surrounded by a ceramic tube (114). The single-piece high-pressure discharge lamp according to claim 7, wherein a part of the lead (115) surrounded by the ceramic tube (114) is surrounded by an insulating material of the inner part (111) of the base.

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