Electric lamp
Patent Information
- Application Number
- HU1999001566
- Authority / Receiving Office
- HU · HU
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 1997-04-17
- Filing Date
- 1997-04-17
- Publication Date
- 2000-08-28
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
Existing electric lamps, particularly automobile headlight lamps, face issues with moisture ingress leading to corrosion of internal components due to the lack of a reliable sealing mechanism, often requiring the use of putty or pouring compound for sealing.
The lamp head is designed with a connection part made of insulating material, featuring a cavity with shaped elements made of heat-resistant, flexible material that securely house current leads, using a press fit and a snap-on lid to ensure a gas-tight seal, eliminating the need for putty or pouring compound.
This design provides a reliable, gas-tight seal that prevents moisture ingress, enhancing the durability and performance of the lamp by preventing corrosion, while simplifying the manufacturing process.
Abstract
Description
The invention relates to an electric lamp with a lampshade and current leads leading out of the lampshade, as well as a lamp head having a connection part made of electrically insulating material and provided with electrical connectors, and - the connecting part has a cavity into which at least one of the current leads of the electric lamp extends, and - at least one electrical connector of the lamp base is formed by a contact tongue, which extends into the cavity of the connector part and is there electrically connected to one of the current leads of the lamp. An electric lamp of the type described in the introduction is disclosed, for example, in patent document EP 0 172 529. This document describes an electric incandescent lamp, primarily a car headlight lamp, which has a lamp cover flattened on one side and a lamp head consisting of metal and plastic parts. The flattened leg of the lamp cover is fixed in the metal support part of the lamp head, while the electrical connections of the lamp, designed as contact tongues, are arranged in the lower part of the lamp head made of plastic. The lower part of the lamp head has a cavity into which the current leads of the lamp, which are led out of the flattened leg, extend. These current leads are welded together with one end of a contact tongue in the cavity of the lower part of the lamp head. In order to seal the lamp head, the cavity is filled with a casting compound. This seal ensures that moisture cannot penetrate the headlight through the lamp head, which would cause corrosion of the reflector. The object of our invention is to provide an electric lamp with a gas-tight lamp head which has an improved construction and, in particular, does not require the use of putty or casting compound for sealing. This problem is solved according to the invention by: - one or more shaped elements are placed in the cavity of the connecting part, which are made of heat-resistant elastic material, - the profile element or profile elements have one or more passages for each current supply of the electric lamp, - the shaped element or shaped elements are mounted on at least one contact tongue and are pressed into place on the wall delimiting the cavity and on the current leads passed through. The electric lamps according to the invention have a lamp cap. The lamp cap has a connection part made of electrically insulating material, in which the electrical connections of the lamp are arranged. The connection part has a cavity into which one or more current leads led out of the lamp shell extend. The current leads are connected there in a conductive manner to an end of the electrical connector designed as a contact tongue. The lamp cap is sealed according to the invention by one or more shaped elements provided with leads for the current leads, which are made of a heat-resistant, elastic and slightly compressible material. The shaped element or elements rest on at least one contact tongue and are pressed onto the wall delimiting the cavity and onto the current leads led through. The press fit is preferably created by at least one contact tongue, which exerts pressure on the shaped element or elements.In addition, the shaped elements are preferably arranged in a correctly aligned recess. In this way, the pressure exerted on the shaped element or elements by at least one contact tongue is distributed evenly over the entire body of the shaped element or elements, and an optimal press fit of the shaped element or elements on the adjacent walls of the cavity and on the current lead or current leads introduced is achieved. In the preferred embodiment, the shaped element or elements preferably consist of silicone. It has proven useful to use several relatively thick-walled, hose-like silicone shaped elements, each of which has a passage for the current leads extending into the cavity of the connection part. The ends of the contact tongues that extend into the cavity are preferably designed as nails and hook or catch on the wall of the cavity. This allows the contact tongues under mechanical tension to be securely pre-fixed before the contact tongues are welded to the current leads. In order to facilitate the welding of the current lead and the associated contact tongue, the contact tongues are each provided with a through-hole for the current lead. The feedthroughs for the contact tongue or contact tongues in the connecting part of the lamp cap are preferably provided with an introduction slope, which enables the contact tongues to be introduced obliquely onto the geometric axis of the lamp cap and the subsequent tilting of the contact tongues into the geometric axis of the lamp cap. The cavity of the connection part is closed by a cover which has a tongue extending into the cavity. This tongue sits on the surface of the contact tongue or contact tongues facing away from the fitting elements. The connection part of the lamp head is made of heat-resistant plastic. Our invention is described in more detail in connection with its exemplary embodiment with the help of our drawings, of which the Figure 1 is a schematic cross-section of a preferred embodiment of the electric lamp, the Figure 2 shows a cross-section of the connecting part of the lamp head of the preferred embodiment of the lamp according to Figure 1, Figure 3 is a top view of a second embodiment of the contact tongue, Figure 4 is a side view of the second embodiment of the contact tongue according to Figure 3. The preferred embodiment of the electric lamp according to the invention is a single-filament halogen incandescent lamp for use in a motor vehicle headlight. This lamp has a substantially cylindrical glass lamp cover 10 with a solidly flattened lamp cover end 10a, which is generally referred to as a flattened foot. The dome part 10b of the lamp cover 10 is provided with a black light-absorbing coating. A filament 10c parallel to the geometric axis of the lamp cover 10 serves as a light source. HU 221 363 Bl, which is connected in a conductive manner to the current leads 11 leading out of the lamp cap end 10a. The lamp cap 10 is fixed in a metal support part formed as a fixing ring 12 with the lamp cap end 10a. The fixing ring 12 is carried by an annular metal support sleeve 13. Four welding tongues 13a are formed on the support sleeve 13, which are welded to the fixing ring 12 by spot welding or laser welding. In addition to the metal fixing ring 12 and the metal support sleeve 13, the lamp head also has a plastic lamp head part 14 provided with the electrical connectors of the lamp, which is fixed in the support sleeve 13. This plastic lamp head part 14 forms the connection part of the lamp head. The electrical connections of the lamp are designed as contact tongues 15 and are welded together with a current supply 11. The plastic lamp head part 14 is an injection-molded part into which the metal holding sleeve 13 is molded.Three reference lugs 14a, which are equidistant from each other along the circumference of a circle, are formed on the plastic lamp head part 14, which serve to adjust the filament 10c and to secure the lamp in the reflector 17 of the headlight. The reference lugs 14a, which extend into the opening 17a of the reflector 17, which is designed as a lamp holder, are covered by a covering strap 13b, which is designed on the holding sleeve 13 and bent at an angle therefrom, and thus shield them from the infrared radiation generated by the filament 10c. The plastic lamp head part 14 also has a circular, conical groove 14b in which a rubber or silicone sealing ring 16 is placed. The sealing ring 16 rests on the outer side of the wall of the reflector 17 and seals the opening 17a of the reflector, which is designed as a lamp holder. The inner diameter of the sealing ring 16 is correctly aligned with the conical groove 14b and varies linearly with the height of the sealing ring 16.The three reference lugs 14a, the sealing ring below and the clamping spring 13c formed on the metal support sleeve 13 under one of the reference lugs 14a serve to fix the lamp in the required position in the aperture 17a of the reflector (in the lamp socket). The lamp head and the aperture 17a (lamp socket) form a bayonet lock. Details of the plastic lamp head part 14 forming the connection part are shown in Figure 2. For the sake of clarity, the lamp cover end 10a is not shown in Figure 2, and the power leads are only shown in part, i.e. not in their full length. The plastic lamp head part 14 has a cavity 18 into which the current leads 11 leading out of the lamp head end 10a of the lamp bulb 10 and the ends of two contact tongues 15 extend. The cavity 18 contains two hose-like silicone shaped elements 19, which are each placed in a correctly fitted recess 18a formed by the walls of the plastic lamp head part 14. The outer diameter of the hose-like shaped elements 19 is much larger than their inner diameter. Each current lead 11 is guided through a passage through a hose-like shaped element 19 and through an opening 15b of the end of the contact tongue 15 welded to it that extends into the cavity 18. The shaped elements 19 sit on a contact tongue 15 each. Each contact tongue 15 then exerts pressure on the corresponding shaped element 19, so that it is slightly compressed into the hose shaft and consequently rests with a press fit on the walls delimiting the recess 18a and on the current supply 11 that is passed through. In this way, a gas-tight seal of the lamp base is ensured in the vicinity of all current supplies. The tongue ends 15a of the contact tongues 15 extending into the cavity 18 are designed like nails and cling to the back wall of the plastic lamp base part 14. In the plastic lamp base part 14, there is an inlet slope 20a on the leads 20 for the contact tongues 15. The inlet slopes 20a facilitate the installation of the contact tongues 15. The cavity 18 is closed by a snap-on cover 21. A tongue 22 extending into the cavity 18 is formed on the inner side of the cover 21, which sits on the surface of the contact tongues 15 facing away from the form elements 19 and provides additional support for the contact tongues 15 under mechanical tension. When assembling the lamp, after the fixing ring 12 holding the lamp cap end 10a has been fixed on the holding sleeve 13, the hose-like fitting elements 19 are threaded onto the given current supply 11 and inserted into the given correctly aligned recess 18a. Then, starting from the cavity 18, the contact tongues 15 are guided along the introduction slopes 20a inclined relative to the geometric axis AA of the lamp head through the leads 20 in the plastic lamp head part 14, and then the contact tongues 15 are tilted into the geometric axis AA of the lamp head, so that the current supply 11 is threaded through the opening 15b of the corresponding contact tongue 15. The hose-like shaped elements 19 are then pressed into the recesses 18a via the contact tongues 15 and slightly compressed, so that the shaped elements 19 lie with a press fit on the walls delimiting the recesses 18a and on the current leads 11 guided through the shaped elements 19.At the same time, the nail-like tongue ends 15a of the contact tongues 15 engage the rear wall of the plastic lamp base part 14 when the contact tongues 15 are tilted into the geometric axis AA of the lamp base. The axial adjustment of the contact tongues 15 is thus pre-fixed. The ends of the current leads all protruding through the openings 15b are then welded to the contact tongues 15, and the cavity 18 is then closed with the snap-on cover 21. Figures 3 and 4 show a second embodiment of a contact tongue. The contact tongue according to the second embodiment has a rectangular contact surface 15d', which is provided with a breakthrough 15b' for a current supply 11. The contact surface 15e' is formed on the contact surface 15d'. The contact surface 15d' and the contact surface 15e' are perpendicular to each other and are connected by a twisted part 15f. A total of three nails, 15a', 15c', are formed on the contact surface 15d', which presses the form element 19, which grip the wall of the lamp base when the contact tongue 15' is mounted. Among these nails 15a', 15c', two nails 15a' are formed on the side of the bearing surface 15d' opposite the contact surface 15e', while the third nail 15c' is formed on the same side of the bearing surface 15d'. HU 221 363 Β1 va, as the contact surface 15e'. Unlike the contact tongue 15 according to the first embodiment, the claw 15a', 15c' is not bent at an angle with respect to the contact surface 15d', but is arranged in the same plane. The invention is not limited to the embodiments described in more detail above. Instead of several hose-like shaped elements, for example, a single shaped element can be used, which consists of a heat-resistant, flexible and slightly compressible material and is provided with several leads for each current supply led out of the lamp shell. Furthermore, the shaped elements do not have to consist of silicone, but can also be made of another material whose heat resistance, flexibility and compressibility are similar to those of silicone. In addition, the ends of the contact tongues that extend into the cavity of the plastic lamp base part can, for example, snap behind a protrusion on the wall of the cavity. They do not necessarily have to be designed like nails. Thermosetting and thermoplastic plastics generally used in lamp manufacturing technology are suitable as materials for the plastic lamp base part 14.
Claims
PATENT CLAIMS 1. An electric lamp with a lamp cover (10) and current leads (11) leading out of the lamp cover (10), and a lamp head, the connection part of which is made of electrically insulating material and provided with electrical connectors, preferably a lamp head part (14), and - the connection part has a cavity (18) into which at least one current lead (11) of the electric lamp extends, and - at least one electrical connector of the lamp head is formed by a contact tongue (15), which extends into the cavity (18) of the connection part and is connected there in a current-conducting manner to one of the current leads (11) of the lamp, characterized in that - one or more shaped elements (19) are arranged in the cavity (18) of the connection part, which consist of a heat-resistant elastic material, - the shaped element (19) or shaped elements (19) have one or more leads for the electric lamp for each current supply (11), - the shaped element (19), or shaped elements (19) are mounted on at least one contact tongue (15),and are pressed into place on the wall delimiting the cavity (18) and on the current leads (11) that are passed through., 2. Electric lamp according to claim 1, characterized in that the shaped element (19) or shaped elements (19) consist of a heat-resistant, flexible and slightly compressible material.
3. Electric lamp according to claim 1 or 2, characterized in that the profile element (19) or profiles (19) are arranged in a correctly aligned recess (18a).
4. Electric lamp according to claim 1, characterized in that the shaped element (19) or shaped elements (19) consist of silicone.
5. Electric lamp according to claim 3, characterized in that there is exactly one hose-like shaped element (19) for each current supply (11) extending into the cavity of the connection part.
6. Electric lamp according to claim 1, characterized in that a press fit is created by at least one contact tongue (15) exerting pressure on the shaped element (19) or shaped elements (19).
7. Electric lamp according to claim 1, characterized in that the tongue end (15a) of the at least one contact tongue (15) extending into the cavity is caught or gripped by a wall of the lamp cap.
8. Electric lamp according to claim 7, characterized in that the tongue end (15a) of the at least one contact tongue (15) extending into the cavity (18) is designed as a nail.
9. Electric lamp according to claim 1, characterized in that the at least one contact tongue (15) is provided with a breakthrough (15b) for the current supply (11) connected thereto.
10. Electric lamp according to claim 1, characterized in that the connecting part of the lamp head consists of heat-resistant plastic.
11. Electric lamp according to claim 1, characterized in that the connection part has a passage (20) for at least one contact tongue (15), which is provided with an introduction slope (20a), which allows the contact tongue (15) to be introduced obliquely onto the geometric axis (AA) of the lamp head and the subsequent tilting of the contact tongues (15) into the geometric axis (AA) of the lamp head.
12. An electric lamp according to claim 1, characterized in that the lamp head has a cover (21) which closes the cavity (18) in the connecting part.
13. Electric lamp according to claim 12, characterized in that the cover (21) has a tongue (22) extending into the cavity (18) and seating on the surface of the at least one contact tongue (15) facing away from the shaped elements (19).