LAMP SOCKET

Abstract: This invention relates to a childproof lamp socket for light bulbs comprising a holder into and out of which the light bulb is intended to be screwed, the light bulb in screwed position being intended to be in contact with a contacting element for getting current. According to the invention the lampsocket is characterized by the combination of the following features: the holder (4; 19) against the action of the force from a spring means (9; 25) is arranged axially displaceable between an upper position and a lower position inside of a sleeve-formed outer part (1; 17), the holder being rotatable in relation to the outer part in its upper position; the holder (4; 19) at its lower part has a first type of means (14; 20), which are intended to cooperate with a second type of means (15; 21) in the sleeve-formed part (1; 17), when the holder has taken its lower position, whereby the holder cannot rotate in relation to the outer part so that the light bulb can be screwed into and out of the holder; the spring means (9; 25) is arranged in the lamp socket and has such a design and placing that, when screwing the light bulb into and out of, respectively, the holder, the spring means is subjected to compression.

Description: Lamp soc e t . This invention relates to a childproof lamp socket for lighet bulbs comprising a holder into and out of which the light bulb is intended to be screwed, the light bulb in screwed-in position being intended to be in contact with a contacting element for getting current. The problem with conventional lamp coskets is that a child could easily screw out the light bulb of the same and reach the current carrying contacting element with serious damages as a result. Attempts have been made to solve this problem with different technical constructions which have appeared to be too complicated in order to be acceptable in the market. This invention intends to provide a lamp socket which is childproof without being complicated. This has been made possible by the fact that the lamp socket mentioned in the introductory part has the features mentioned in the claims. Two preferred embodiment of the invention shall be described in more detail below with reference to the accompanying drawings, where Fig. 1 shows a lamp socket according to the first embodiment, the lamp socket being shown in axially divided condition so that its interior appears evidently, and Fig. 2 shows a lamp socket according to the second embodiment, which also is shown in axially divided condition. With reference to Fig. 1 is shown there the first embodiment of the lamp socket, which comprises a tubular, essentially circular-cylindrical, outer portion 1 which at its top part is provided with an annular part 2 comprising a bevelled portion 3 being inside, radially seen, the outer part 1 and forming an upper stop portion for a holder 4, designed as an inner part, for the light bulb itself. This holder, which is rotatable relative to the outer part 1, has also an essentially circular-cylindrical design and comprises a threaded hole 5, into which the light bulb shall be screwed in. Right at the top of the holder 4 is arranged an annular, radially outwards-directed projection 6, which is intended to be in contact with partly the portion 3 of the annular part 2, seen in the direction upwards, partly with the inner wall 7 of the outer part 1 , seen in the direction outwards. Due to that fact is formed a cavity 8 between the outer wall of the holder 4 and the inner wall of the outer part 1 and in this cavity is an annular, cylinderlike helical spring 9 or some other spring means arranged. The upper part of this spring means is applied against the underpart of the projection 6 of the holder 4, whereas the lower part of the spring means 9 is applied against a radial, inwards-directed projection 10, which is arranged on the outer part and comprises an enlargement of its wall thickness on an axial portion 11 of the same. This portion extends a bit downwards on the outer portion and passes over to another portion 12, where the wall thickness becomes still larger. The transition part between the portions 11, 12 has a lower, annular stop portion 13 for the holder 4, which is movable down towards this lower position against the action of the spring force of the helical spring 9. In this lower position the holder 4 is intended to be locked regarding rotation in relation to the outer part 1 , which in its upper position is essentially freely rotatable in relation to the outer part 1 of the lamp socket. For this locking reason the holder 4 at its underpart has a plurality of downwards-directed projections 14, which are arranged on the lower part, around the same, of the holder and which are intended to cooperate with corresponding recesses 15, which are made in that portion 12, around the same, of the outer part 1, which has the largest wall thickness. Right at the bottom of the outer part 1 of the lamp socket is on its inner wall arranged a threaded portion 16, on which the bottom section of the lamp socket is intended to be fixed by screwing. This bottom section comprises a fixed contacting element for electric current to the light bulb. The device functions in the following way, the holder being in its upper position, shown in Fig. 1 , where the holder 4 can rotate in relation to the outer part 1. The light bulb is applied against the threaded hole 5 of the holder 4 and is forced to push down the holder against the action of the spring means 9, so that the downwards-directed projections 14 of the holder 4 pass into the corresponding recesses 15 in the outer part of the lamp socket. In this position the light bulb can then simply be screwed into the hole 5. Thereafter, the grip of light bulb is released, and the holder 4, due to the action of the spring, takes the position shown in Fig. 1. If there is a wish to screw out the light bulb of the lamp socket, a real force is applied downwards against the light bulb so that the projections 14 go into engagement with the recesses 15, whereafter the light bulb can be screwed loose. It should be realized that the child safety of the lamp socket, when a light bulb is screwed into the same, consists of the fact that a child cannot manage to force the holer 4 downwards against the action of the spring means 9, but the attempts of the child has only that consequence that this inner part 4 with a light bulb screwed into it will rotate in relation to the outer part 1. I Fig. 2 is shown a second embodiment of the invention having great similarities with the first embodiment. Thus, also this lamp socket has an outer part 17, an annular part 18 at the top of the lamp socket, and an inner part 19 in the form of a holder for the light bulb, which holder partly is movable in relation to the outer part in the axial direction of the lamp socket, partly can rotate in relation to the outer part in that position the holder has in the Figure. Furthermore, the lower part of the holder, in similarity with the first embodiment, has a plurality of projections 20, which are intended to cooperate with corresponding recesses, arranged on the inner wall, around the same, of the outer part 17. These recesses can be made in a portion 21, which is integrated with the outer part 17 or in a particular ring 21, which is fastened on the inner wall of the outer part 17. The lower portion of the outer part 17 according to this embodiment in similarily with that according to the first embodiment has a threaded part 22, on which the bottom section 23 of the lamp socket is fixed by screwing. The upper part of this bottom section is provided with a fastening plate 24 for the lower part of a spring means 25, which is centrally positioned in the lamp socket, and which can consist of a spring means. The mentioned spring is intended to cooperate with the light bulb 26. As appears from a comparison between the two embodiments is essentially the only difference the design and position of the spring means. According to the first embodiment is the sleeve-like spring means arranged in the wall portion of the lamp socket, a fixed contacting element being arranged in the bottom section of the lamp socket. According to the second embodiment is the spring means positioned in the bottom section of the lamp socket, the mentioned spring means carrying the contacting element 27 for electric current. When putting in a light bulb 26, this one is screwed into the holder 19 against the action of the spring 25, In this connection the holder 19 is in its lower position, whereby the projections 20 are locked in the recesses of the portion 21. When the light bulb is entirely screwed in and the grip of the light bulb has been released, the holder 19 with the light bulb, screwed in, is displaced upwards so that the holder takes its upper position shown in Fig. 2. In this position the holder can rotate in relation to the outer part 17 of the lamp socket. A child that cannot force down the spring 25 can accordingly not screw loose the light bulb, but this one will only rotate in relation to the outer part of the lamp socket during the attempts of the child for screwing loose the light bulb. The lamp socket is made of a suitable material, for instance plastics and/or metal. The invention is of course not limited to the mentioned embodiment but can be modified within the scope of the following claims.

Claims: Claims 1. A childproof lamp socket for light bulbs comprising a holder into and out of which the light bulb is intended to be screwed, the light bulb in screwed - in position being intended to be in contact with a contacting element for getting current, characterized by the combination of the following features: - The holder (4; 19) against the action of the force from a spring means (9; 25) is arranged axially displaceable between an upper position and a lower position inside of a sleeve-formed outer part (1; 17), the holder being rotatable in relation to the outer part in its upper position; - The holder (4; 19) at its lower part has a first type of means (14; 20), which are intended to cooperate with a second type of means (15; 21) in the sleeve-formed part (1; 17), when the holder has taken its lower position, whereby the holder cannot rotate in relation to the outer part so that the light bulb can be screwed into and out of the holder; - The spring means (9; 25) is arranged in the lamp socket and has such a design and placing that, when screwing the light bulb into and out of, respectively, the holder, the spring means is subjected to compression. 2. A lamp socket according to claim 1, characterized in that it has a sleeve- formed cavity (8) between the outer wall of the holder (4) and the inner wall of the outer part (1), and that the spring means (9), compressible in the axial direction, is arranged in this cavity. 3. A lamp socket according to claim 1, characterized in that the spring means (25) is arranged in the lower part of the lamp socket and has the contacting element (27) for electric current on its topside. 4. A lamp socket according to any one of the preceding claims, characterized in that the first type of means comprises downwards-directed projections (14; 20), and that the second type of means comprises cooperating recesses (15; 21).

Inventors: BURVALL MIKAEL, BURVALL, MIKAEL
Applicants: BURVALL MIKAEL, BURVALL, MIKAEL
Application year: 1998
Main classification: H01R33
IPC codes: H01R33