Patent Grant
6946782
1. Field of the Invention
The invention concerns a connector system for a rod-shaped two-ended discharge lamp, in particular a mercury high pressure lamp or a mercury medium pressure lamp, with two lamp bases provided at the connector ends of the discharge lamp and two insert sockets for receiving the lamp bases mounted spaced apart from each other in a lamp housing.
2. Description of the Related Art
Taking advantage of their emission in the UV-range, mercury high and medium pressure lamps are employed in radiation devices for many applications for influencing surfaces, in particular for environmentally safe hardening or curing of coatings, printing inks and paint. Depending upon soiling and wear, the lamp must be cleaned at intervals or, as the case may be, must be changed out. It is also necessary to remove the lamp for access to other component parts which must be serviced, such as reflectors. Thereby appropriate safety procedures must be met, since such UV-lamps are driven by high voltage and warm up to high temperatures during operation. With conventional connector systems for such lamps the voltage conducting connector cables to the lamp bases are materially joined with the electrode system. The removal of the lamp thus requires a work intensive disconnecting and freeing of the connector cables in the carrier housing under confined conditions. For this reason, it is often the case that essential cleaning operations or a necessary lamp change-out is postponed longer than necessary. In addition to this, there are safety problems due to metal parts which can be contacted, which can be subjected to voltage in the case of an accident during installation of the lamp. Further, it is frequently the case that such open conductor parts must be kept free relative to conductive housing parts by sufficient insulation areas, which leads to a reduced radiation zone for a given housing dimension.
Beginning therewith, it is the task of the present invention to provide a connector system which overcomes the above mentioned disadvantages and provides with a compact construction a simple assembly and high operational safety.
The invention is based upon the concept, of combining a simple mounting for the lamp with a reliable contact establishment. In accordance therewith it is proposed that the lamp bases which are respectively provided spaced apart at the connecting ends of the lamp longitudinal direction are provided with a contact pin connected electrically with a lamp electrode as well as an insulation housing surrounding the contact pin on all sides while however keeping open a side or lateral connector opening, and that the assembled unit includes respectively one contact element insertable through the connecting opening of the associated lamp base and releaseably contacting with the contact pin, and via connecting lines is energizable with high voltage, as well as an insulating body which carries the contact element and in the connected condition covers over the connection opening. Therewith, the possibility of a rapid replacement, with good all around insulation in the connected condition, is insured.
A particularly advantageous and reliable contact production is achieved thereby, that the contact pins are insertable and removable without tools from a slot extending radially perpendicular to the lamp longitudinal axis with production of a clamp connection with the contact elements.
In order to further simplify the insertion or plug-in mechanism, it is proposed that the contact elements are formed by a U-shaped spring contact, of which the spring shanks with their each other facing contact sides are spreadable under spring tension against the contact pin.
A further improvement of the contact production and contact effect can be achieved thereby, that the spring shanks of the spring contact exhibit an arch-shaped bent contact segment and an end segment bent or angled outwards, away from the contact side which lies flush against the contact pin over a partial circumference, wherein the gap-width of the insertion gap bordered by the end segments is smaller than the diameter of the contact pin.
It is also advantageous when the contact element can be anchored to the insulation body via a connection part which at the same time is connectable with the connection circuit. In order to insure a complete contact even in the case of deviations in form and position, it is advantageous when the contact element is mounted “floating” in the insulation body with free play. This can be accomplished for example by a spring disk formed by a spring element. Preferably, the connection part is formed by a core piece provided between the spring shanks of the spring contact and a threaded shaft formed on the core piece extending through the spring contact on its spring shank connecting base.
A particularly preferred shock protection and a secure covering-over of the conductive parts is advantageously achieved thereby, that the insulation body includes a U- or C-shaped support part, on the inner side of which the contact element is provided extending centrally. In a mechanically advantageous embodiment it is envisioned that the contact element is maintained fixed against rotation in a recess of the insulation body.
For simplification of assembly it is proposed that the insulation body exhibits a flange formed at the end side of the support part for securing to the lamp housing. Preferably the contact pin in the form of a hollow cylinder pin is internally contactable with a connection wire of the associated lamp electrode.
In order to facilitate the engagement of the contact element, it is proposed that a ring space is maintained free between the insulation housing and the therein concentrically provided contact pin.
For centering and supporting it is advantageous when the contact pin, on its end segment facing the discharge lamp, exhibits a radially projecting collar or flange lying against the inside of the insulation housing.
In order to ensure a sufficient mechanical rigidity or stability, it is advantageous when the insulation housing includes a support segment receiving the connecting end of the discharge lamp, preferably sealed with a ceramic cement, and a connection opening associated free end formed for mounting the contact pin. Therein it is advantageous when the end of the collar or flange of the contact pin borders the inner space of the support segment of the insulation housing.
Advantageously the contact pin is mounted or carried by its free end preferably formed by a narrowing centering connection projection supported in a central recess of an end wall forming the free end of the insulation housing. The insulating end wall makes it possible to dispense with further insulation segments in the lamp longitudinal direction, so that a compact apparatus design is made possible.
With respect to the mechanical stabilization a further improvement is achieved thereby, that the insulation housing includes a flattened wall part bordering on the connection opening, extending axially to a lamp end side, which in the connected condition comes into alignment with a facing plane surface of the insulation body.
In order to simplify the engagement of the contact element and to keep free a sufficient contact surface, it is advantageous when the connection opening viewed in the circumference direction of the insulation housing of the base exhibits an opening angle of at least 120° and in the axial direction of the insulation housing exhibits an opening breadth of at least 5 mm, preferably 10 mm.
Preferably, the insulation housing of the base and the insulation body respectively are comprised of a one-piece shaped part of an electric insulating, thermally conductive and heat resistant material, preferably a ceramic material.
In order to achieve a low transition or contact resistance and a high durability or longevity, it is of advantage, when the contact element and/or the contact pin are comprised of a stainless steel or copper or a copper-beryllium-alloy and in certain cases are coated or plated with an electrically highly conductive, non-oxidizing surface layer, preferably of gold or silver.
A further aspect of the invention concerns a discharge lamp, in particular a mercury discharge lamp or mercury medium discharge lamp for employment in an UV-radiating device, with sockets on two sides, a rod-shaped discharge lamp and an inventive connection device.
In the following the invention will be described in greater detail on the basis of the illustrative embodiment represented in schematic manner in the figures. There is shown
FIG. 2 and
FIG. 4 and
The connection device 10 shown in the figure or, as the case may be, connection fitting or mounting, serves for rapid replaceable mounting and for electrical connection of a rod shaped mercury vapor gas discharge lamp 12 in a housing 14 of a not shown UV-radiating device. It is comprised of essentially one lamp base 20 provided on the two connector ends 16 of the discharge tube 18 of the discharge lamp 12 as well as respectively one insert socket 22 for receiving the associated lamp bases or base 20.
The lamp bases 20 respectively exhibit one contact pin 26 projecting axially at the connector end 16, that is, in the direction of the lamp longitudinal axis 24, as well as a basically cylindrical ceramic insulating cylinder 28 provided co-axially to the contact pin 26. The contact pin 26 is designed as a hollow cylinder pin and is welded internally to a connection wire 30 extending out from the connector end, which is in electrical contact, via a metal band piece 32 extending through the glass melt 34, with a coiled pin electrode 36 projecting into the discharge tube 18. On its lamp end the contact pin 26 exhibits a radially projecting plate-shaped flange 38, which lies radially against the inner wall of the insulation housing 20.
The support segment 40, on the lamp-end of the insulation housing of the base 20, surrounds the connector end 16, and is form-fittingly connected therewith via a ceramic cement 42. On its end the connection area is separated by a flange 38 from a contact pin 26 receiving free end segment 44 of the insulation housing 20. The end segment 44 is provided with a lateral connector opening 46 formed by a radial interruption or through hole of the housing, which over the remainder however is closed off on all sides, keeping free a ring space 48 with respect to the contact pin 26. The connection opening 46 extends over an opening angle of approximately 160° in the circumference direction and has an axial opening breadth of approximately 10 mm. At its free end wall 50 the insulation housing of the base 20 exhibits a central, inwardly open blind borehole 51, in which the contact pin 26 is supported via a centering connector piece 52 which narrows toward the end. An inner shoulder 54 of the insulation housing 20 forms an abutment for the contact pin 26, wherein the collar or flange 38 thereof is provided for compensating differential thermal expansions in axial distance from the inner shoulder 54.
The insert socket 22 is comprised of a spring contact which can be brought into clamping contact with the contact pin 26 and via a connection cable 56 is chargeable with high voltage (greater than 1 kV) as well as a ceramic insulation body 60 carrying the spring contact 58. As can be best seen from
The insulation body 60 exhibits a receiving part 70 in the form of a U-shaped profile piece for receiving the lamp base 20 and a flange 72 formed on the end face of the receiving part 70 for a screw connection to the housing 14. The receiving part 70 is internally provided on its cross-piece 74 with a longitudinal groove 76, in which the spring contact 58 is maintained fixed against rotation on its base. For anchoring the spring contact 58 a core piece 78 is riveted between the spring shanks 62, which via a threaded shaft 80 extends through the cross piece 74 of the receiving part 70 and which on its back side is supported by means of a nut 82 (FIG. 1). On the projecting free end of the threaded shaft 80, a threaded socket 84 forming a connector socket for a connection cable 56 can be screwed on, which for its part in the assembled condition is insulated by a ceramic sleeve nut or cap or bushing 86. In order to further reduce the contact resistance, the core piece 78 on its contact side 88 lying against the contact pin 26 is formed concave complimentary to the outer contour thereof. For mechanical stabilization, the support segment 40 of the insulating cylinder 28 exhibits a flattened wall part 90 (
The discharge lamp 12 with its lamp base 20 can be assembled to and again removed in simple manner without tools from the insert sockets 22. Thereby the contact pins 26 are brought into engagement or, as the case may be, again released from engagement with the spring contacts 58 in a joining device running transverse to the lamp longitudinal axis 24. The free ring space 48 makes possible a corresponding spreading apart of the spring shanks 62. The receiving part 70 of the insulation body 60 covers over in the connected state the connection opening 46 of the insulating cylinder 28, so that an all side insulation in a safe protection from contact is achieved.
| Number | Date | Country | Kind |
|---|---|---|---|
| 199 55 979 | Nov 1999 | DE | national |
This application is a national stage of PCT/EP00/09064 filed Sep. 16, 2000 and based upon DE 199 55 979.1 filed Nov. 20, 1999 under the International Convention.
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/EP00/09064 | 9/16/2000 | WO | 00 | 5/20/2002 |
| Publishing Document | Publishing Date | Country | Kind |
|---|---|---|---|
| WO01/39237 | 5/31/2001 | WO | A |
| Number | Name | Date | Kind |
|---|---|---|---|
| 4687965 | Sanders et al. | Aug 1987 | A |
| 4751422 | Moianz et al. | Jun 1988 | A |
| 4879491 | Hirozumi et al. | Nov 1989 | A |
| 4906891 | Takagi et al. | Mar 1990 | A |
| 4928210 | Hayakawa et al. | May 1990 | A |
| 4949007 | Takagi et al. | Aug 1990 | A |
| 5036439 | Hoffmann et al. | Jul 1991 | A |
| 5221874 | Dayton | Jun 1993 | A |
| 5266866 | Takagi et al. | Nov 1993 | A |
| 5296780 | Haraden et al. | Mar 1994 | A |
| 5479066 | Willems et al. | Dec 1995 | A |
| 5696424 | Coushaine | Dec 1997 | A |
| 5709450 | Francis et al. | Jan 1998 | A |
| 6005336 | Helbig et al. | Dec 1999 | A |
| 6270235 | Coushaine | Aug 2001 | B1 |
