WO2008136687A1

WO2008136687A1 - A light assembly with lock arrangement

Info

Publication number: WO2008136687A1
Application number: PCT/NZ2008/000062
Authority: WO
Inventors: Thomas Mackenzie
Original assignee: Intellectual Property Energy Mad Limited
Priority date: 2007-05-07
Filing date: 2008-03-20
Publication date: 2008-11-13
Also published as: NZ555021A

Abstract

A light assembly including a light socket and an electric lamp, wherein the light socket includes a connection base with at least two conductor-openings and a lock-opening having a lock portion and an open portion, and the lamp includes a light source, a connection base with two conductive protrusions to engage with the socket conductor- opening and a locking-protrusion on the lamp connection base shaped and/or sized for insertion into the open portion of the socket lock-opening and movement into the lock portion only after insertion into said open portion. The locking protrusion, lock-opening and conductor-openings are respectively configured to allow relative movement of the lamp connection base with respect to the socket connection base to effect the attachment and removal of the lamp from the socket via the lock-opening.

Description

A light assembly with lock arrangement

Technical Field

The present invention relates to a light assembly.

In particular, the present invention relates to a light socket and electric lamp, configured to provide an improved physical connection therebetween. Background Art

For clarity and brevity the "electric lamp" will herein be referred to as a "light bulb", though this should not be seen to be limiting as it will be appreciated the present invention may be adapted for any electric lamp or light source. Light bulbs generally connect to an associated light socket via one of three main connection types, i.e. bayonet, screw, or friction fit. While the bayonet and screw type connections provide a higher level of securement than friction fit connections they are often more expensive and may have exposed conducting portions that present an electrocution risk to persons installing or removing the bulb. Friction fit connections are thus increasingly being used to replace bayonet and screw configurations as the preferred connection type.

A typical friction fit light bulb includes two conducting pins protruding from the non- conductive light bulb base. These pins are inserted into corresponding light socket recesses which have biased conductive sheaths or the like into which the pins are inserted. The pins and bulb are thus retained by the frictional force between the pins and biased sheaths. While a pin friction fit configuration may be inexpensive to manufacture, as time passes the bias and level of friction may decrease and thus increase the risk of inadvertent disconnection. Furthermore, without a locking securement the light bulb may be disconnected if knocked or shaken. One attempt at improving friction-fit connections is provision of an additional non-conductive coupling such as spring clips that engage with protrusions on the bulb base. However, provision of spring clip attachments adds cost and complexity to the manufacturing of both the socket and bulb. Another disadvantage of typical friction-fit connections is the risk of injury or overextension when removing the lamp, i.e. a person must pull the bulb from the socket against an unknown frictional force, often while standing at height on a chair or ladder.

It would thus be advantageous to provide a connection between a light bulb and light socket that provides the advantages of a friction fit electrical connection while also providing an improved secure connection that inhibits inadvertent disconnection. It would also be advantageous to provide an improved light bulb and socket without substantial increase in manufacturing cost or complexity.

All references, including any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein; this reference does not constitute an admission that any of these documents form part of the common general knowledge in the art, in New Zealand or in any other country.

It is acknowledged that the term 'comprise' may, under varying jurisdictions, be attributed with either an exclusive or an inclusive meaning. For the purpose of this specification, and unless otherwise noted, the term 'comprise' shall have an inclusive meaning - i.e. that it will be taken to mean an inclusion of not only the listed components it directly references, but also other non-specified components or elements. This rationale will also be used when the term 'comprised' or 'comprising' is used in relation to one or more steps in a method or process. It is an object of the present invention to address the foregoing problems or at least to provide the public with a useful choice. Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only. Disclosure of Invention

According to a first aspect of the present invention there is provided a light socket for connecting an electric lamp thereto, the light socket including: - a connection base including at least two conductor-openings adapted to receive two conducting protrusions on a base of said lamp, each conductor- opening including therein at least one electrically conductive portion adapted to contact the protrusions and provide an electrical connection therebetween, and characterised in that said socket includes: - a lock-opening having a lock portion and an open portion which are respectively connected to one another, said open portion shaped and/or sized to allow for passage of a locking protrusion on the base of said lamp, the lock portion of the lock-opening shaped and/or sized to retain the locking protrusion therein (lock position) until the locking protrusion is moved to the open portion (detach position); the locking-protrusion, lock-opening and conductor-openings being respectively configured to allow relative movement of the lamp base with respect to the socket connection base to effect the attachment and removal of the lamp from the socket via the lock-opening. A light socket substantially as described above where the socket is further characterised in that the electrically conductive portion is adapted to be capable of contacting said conducting protrusions when the locking protrusion is located in the lock portion.

According to a second aspect of the present invention there is provided an electric lamp for connection to a light socket, the lamp including;

- an electric light source for emitting light,

- a connection base including two conductive protrusions for passing electricity to said light source, each protrusion configured to engage with a socket conductor-opening and conducting portion therein, and characterised by the further inclusion of a locking protrusion shaped and/or sized for insertion into an open portion of a socket lock-opening and for movement into a lock portion of the lock opening only after insertion of the lock protrusion into said open portion. According to a third aspect of the present invention there is provided a light assembly including a light socket and an electric lamp, said assembly including: a light socket including:

- a connection base including at least two conductor-openings adapted to receive two conducting protrusions on the lamp, each conductor-opening including therein at least one electrically conductive portion adapted to contact the protrusions and provide an electrical connection therebetween, and

- a lock-opening having a lock portion and an open portion which are respectively connected to the connection base, said open portion shaped and/or sized to allow for passage of a locking protrusion on a connection base of said lamp, the lock portion of the lock-opening shaped and/or sized to retain the locking protrusion therein (lock position) until the locking protusion is moved to the open portion (detach position); and a lamp including:

- an electric light source for emitting light, - a lamp base including two conductive protrusions for passing electricity to said light source, each protrusion configured to engage with the socket conductor- opening and conducting portion therein, and

- a locking-protrusion on said lamp base shaped and/or sized for: (a) insertion into the open portion of the socket lock-opening; and

(b) movement into the lock portion only after insertion into said open portion, the locking protrusion, lock-opening and conductor-openings being respectively configured to allow relative movement of the lamp base with respect to the socket connection base to effect the attachment and removal of the lamp from the socket via the lock-opening.

A light assembly substantially as described above wherein the conductive portions are adapted to be capable of contacting said lamp conducting protrusions when the locking-protrusion is moved in to the lock portion. According to another aspect of the present invention there is provided a method of reversibly connecting an electric lamp as aforementioned to a light socket as aforementioned, said method including the steps of:

- aligning a locking-protrusion on the lamp base with a corresponding lock- opening open portion on a light socket connection base, - inserting the locking-protrusion through said open portion and at the same time inserting the lamp conducting protrusions into respective socket conductor-openings, and moving the locking-protrusion from said open portion into said lock portion to effect the reversible attachment of the lamp to the socket. The present invention as aforementioned and as described herein is described with reference to the lock-opening and conductor-openings being provided in the socket connection base and the locking-protrusion and conducting-protrusions provided on the lamp connection base. However, it will be appreciated that reverse configurations are possible and are considered within the scope of the present invention. For example, the lock-opening may be provided on the lamp base and the locking- protrusion on the socket base and/or the conducting-protrusions may be provided on the socket base and the conductor-openings on the lamp base. The socket connection base and lamp base may be made from a non-conductive material. Preferably, the socket connection base and lamp base may be made from plastic. Preferably, said lamp conducting protrusions are formed as pins or the like. For ease of reference the lamp conducting protrusions will now be referred to as pins, although this should not be seen to be limiting.

Preferably, said electric lamp has a light source in the form of a light bulb. For ease of reference the electric lamp will now simply be referred to as a lamp. However, this should not be seen to be limiting as in some embodiments the electric lamp may have a light source in the form of fluorescent light tubes, light emitting diodes or diode arrays, neon, halogen or light sources. Preferably, said socket conductor-openings and conducting protrusions, are respectively, located laterally to said socket lock-opening and lamp locking-protrusion. Preferably, said socket lock-opening and lamp locking-protrusion are located substantially centrally on the respective socket connection base and lamp base. In some preferred embodiments the conductive portion is configured to maintain electrical contact with said lamp conducting protrusions during said relative movement.

It will be appreciated that the conducting portions of each conductor-opening and the conducting protrusions of the light bulb may be constructed from any electrically conductive material or may include a combination of materials such that the final composite material is substantially electrically conductive. In one embodiment said socket conducting portions are releasably attached to said conductor-openings to facilitate easy removal and replacement. Preferably, the conductor-openings and conducting portions are configured such that the pins may only contact said conducting portions upon movement of said locking protrusion from said detach position to said lock position. Thus an electrical connection may be prevented until the bulb is securely connected to the socket. In one preferred embodiment said conducting portions are formed as elongate conducting members attached at a first end to a first side of the conductor-opening and biased toward a second side substantially opposing said first side at, or proximal, a distal end thereof. Thus, a said pin may be inserted into the conductor-opening adjacent the respective conducting portion first end and, upon movement of said locking protrusion from said detach position to said lock position, the pin may move along said conductor-opening into contact with the conducting portion against said bias. The biased conducting portions may also provide a frictional connection with said pins and thus indicate to a user a secure connection as the pins move against the friction and bias. It will be appreciated that the level of frictional contact may be varied by adjusting the level of bias and/or by tapering the conductor-opening from said first end to a narrow second end.

In an alternative embodiment said elongate conducting member distal end may be attached to said conductor-opening second side, or a portion proximal thereto. Preferably, at least one said conductor-opening includes two said conducting members on opposing sides of said conductor-opening to thus provide a greater electrical contact area with the bulb pins. Preferably, said relative movement is between: - a detach position wherein the locking protrusion is in said open portion, and a lock position wherein said locking protrusion is retained in said lock portion, It will be appreciated that the socket may be configured such that said relative movement is linear, arcuate, rotational in one or more dimensions or a combination of same. For example, in one embodiment said open portion is located laterally adjacent said lock portion with respect to an insertion axis along which the locking protrusion is moved into said open portion. The relative movement of the locking protrusion between the detach and lock positions may be linear movement along a lock axis orthogonal to said insertion axis to thereby connect the lamp to the socket. In preferred embodiments however, the lock opening is configured to receive a locking protrusion in the form of a twist-lock portion, said lock-opening configured to only allow the insertion of the twist-lock portion when substantially aligned with same, and whereupon insertion of the aligned twist-lock portion through said open portion and subsequent rotation of the lamp base about a twist-lock axis moves the twist-lock portion into the lock-opening lock portion to thus effect a reversible twist-lock connection.

In general the twist lock portion may have one or more arms. In preferred embodiments the twist-lock portion may be substantially T-shaped. However this should be not be seen as limiting. For ease of reference only the twist-lock portion will now be referred to as being T-shaped. However, this should not be seen as limiting. For example, in one embodiment said twist-lock portion may be provided as a T- shaped protrusion.

The lock opening having an aperture having longer dimensions relative to an open portion in the form of a slot extending from sides of the aperture to receive the arms of T-shaped protrusion. Once the T-shaped protrusion has been inserted into the aperture and associated open portion, the bulb is rotated so the arms of the T-shaped protrusion are no longer aligned with the open portion to effect a twist-lock and are constrained by a lock portion, namely the periphery of the aperture. It will be appreciated that numerous other configurations may be utilised such that said lock-opening only permits insertion of the locking protrusion into the lock portion once the locking protrusion is first substantially aligned with said lock-opening open portion and inserted into same.

Preferably, the locking-protrusion is provided as an integral part of the lamp base though it will be appreciated that the locking-protrusion may alternatively be fixed, or releasably attached to said connection base. It will also be appreciated that the locking protrusion may be formed as a single-piece member or as a plurality of discrete pieces.

Preferably, the locking-protrusion is constructed from an electrically non-conductive material, for example,, plastic, glass, rubber, porcelain, ceramic or the like. Preferably said socket is configured to constrain the degree of rotational movement of said bulb once the twist-lock portion is inserted into the open portion of the lock- opening. Preferably, said rotational movement is constrained between:

- the detach position, wherein the arms of the twist-lock portion are substantially aligned with the open portion, and - the lock position, wherein the twist-lock portion is in the lock portion and not aligned with said lock-opening.

Preferably, the range of rotational movement between said detach and lock positions is approximately 70° though this should not be seen to be limiting. The constrained rotational movement may thus provide a user with an indication of when the twist-lock portion and lock-opening open portion are:

- aligned in the detach position to allow removal of the twist-lock portion and thus disconnection of the light-bulb, and non-aligned in the lock position to provide a secure connection, both physical and electrical. It will be appreciated that said rotational movement may be limited by one or more configurations including:

- stops at said detach and lock positions for engaging with said twist-lock portion,

- conductor-openings sized and/or shaped to limit movement of the bulb pins therein, and/or mutually engaging stops or the like on the bulb and socket connection bases.

Preferably, said light assembly is configured such that said bulb twist-lock portion, may only be inserted into said open portion of the lock-opening substantially along the twist-lock axis.

Preferably, the light bulb of the present invention is shaped to be substantially symmetrical about a central bulb axis and in preferred embodiments is configured such that the twist-lock portion only aligns with said lock-opening open portion when said bulb axis is substantially parallel or coaxial with said twist-lock axis. Preferably, said twist-lock portion and receiving lock-opening open portion have substantially the same shape in cross-section through respective planes orthogonal to said twist-lock axis and bulb axis. Thus, the twist-lock portion may only be inserted when the twist-lock portion is substantially aligned and coterminous with the lock- opening open portion. In alternative embodiments the lock-opening open portion and twist-lock portion may not have the same cross-sectional shape.

The present invention may provide significant advantages over prior art light assemblies such as typical friction, bayonet or screw fittings, namely: provision of an improved light socket and associated bulb that may be capable of simple and secure connection without relying on a friction fit or complicated spring-clip engagement; and a light assembly which is economical to manufacture and provides a reliable electrical connection. Brief Description of Drawings Further aspects and advantages of the present invention will become apparent from the following description which is given by way of example only and with reference to the accompanying drawings in which: Figure 1 shows a plan view of a light socket according to one preferred embodiment of the present invention; Figure 2 shows a plan view of a light bulb connection base according to one preferred embodiment of the present invention; Figure 3 shows an exploded side cross-sectional view through A-A of the light socket and light bulb as shown respectively in figures 1 and 2; Figure 4 shows a side cross-sectional view through A-A of the light socket and light bulb with the twist-lock portion in an aligned orientation; Figure 5 shows a side cross-sectional view of the light socket through A-A and light bulb through B-B connected with the twist-lock portion in a non- aligned orientation;

Best Modes for Carrying out the Invention Figures 1-5 show one preferred embodiment of the present invention in the form of a light socket (1) and electric lamp (lamp) (2) for connection thereto. The socket (1) has a connection base (3) with two conductor-openings in the form of arcuate slots (4) for receiving conducting protrusions in the form of lamp pins (5) on a lamp base (6). The bulb (2) has a light source in the form of a bulb having helical glass tube (11) containing halogen gas.

Each slot (4) has a conducting portion in the form of resilient metal strip (7) extending part way across the slot (4) to provide a narrowed portion (8) into which respective lamp pins (5) are moved to contact the strip (7). The metal strips (7) are connected to the light socket circuitry (9) and via socket pins (10) to a power source (not shown) to provide power to the lamp (2) when connected.

The lamp pins (5) and strips (6) are respectively laterally spaced from a locking- protrusion in the form of twist-lock portion (14) and a lock-opening (15) so that when the lamp (2) is rotated about a twist-lock axis (12), the pins (5) move along the conductor-openings (4) into the narrowed portion (8). The narrowed portion (8) thus provides the strips (7) with a frictional contact against the pins (5) to ensure an electrical connection is maintained and to provide force-feedback to a user rotating the bulb (2) to indicate the electrical connection.

The lamp (2) shown in the figures is a typical halogen bulb shaped substantially symmetrical about a central bulb axis (13), as is typical of most light bulbs. Both the light socket (1), conductor-openings (3) and lamp connection base (6) are constructed from plastic to electrically insulate the bulb pins (5) and electrically conductive strips (5) and prevent an electrical connection being formed upon contact with the bulb pins (5) and/or a user's fingers when installing/removing the lamp (2). The socket (1) has a lock-opening (15) for receiving the twist-lock portion (14) provided on the bulb base (5).

The twist-lock portion (14) has a central cylindrical protrusion (14a) and two bayonet lugs (14b) spaced along the central protrusion (14a) from the connection base (6). The lock-opening (15) has an aperture (15a) and an open portion in the form of lateral slot (15b) extending either side of the aperture (15). A lock portion is provided in the form of aperture periphery (15c) which is sized to allow passage of the twist-lock portion central protrusion (14a) but otherwise prevent passage of the bayonet lugs (14b). The lock-opening (15) and twist-lock portion (14) are substantially the same shape and size in cross-section through respective planes orthogonal to the twist-lock axis (12) and bulb axis (13). Thus, the twist-lock portion (14) can only be inserted into the lock-opening (15) when substantially aligned and coterminous with the lock-opening open portion, i.e. bayonet lugs (14b) must be aligned with slots (15b) to thus ensure that a user can only connect the light bulb (2) when the bulb pins (5) and receiving slots (4) are also aligned, thereby ensuring a 'correct' connection. Subsequent rotation of the lamp (2) and twist-lock portion (14) moves the twist-lock portion (14) into the lock portion, i.e. lugs (14b) move behind the periphery (15c). As the lugs (14b) may not pass through the periphery (15c) unless aligned with slots (4) the lamp (2) is prevented from movement along the twist-lock axis (12) and thus ensures a secure connection. The lock-opening (15) has four stops (16) (only two shown) for engaging with the bayonet lugs (14b) to constrain the degree of rotational movement of the lamp (2). The stops (16) are positioned to permit only rotational movement of the twist-lock portion (14) between a 'detach' position (shown in figure 4) for insertion/removal, and a 'lock' position (shown in figure 5) wherein the twist-lock portion (14) is not aligned with the lock-opening (15) and the bulb pins (5) are in contact with the metal strips (7). In the preferred embodiment shown, the stops (16) are positioned to restrict rotational movement to approximately 70°.

This constrained rotational movement thus provides a user with an indication of when the twist-lock portion (14) and lock-opening (15) are: - aligned to permit insertion/removal of the twist-lock portion (14) and thus connection/disconnection of the lamp (2), and non-aligned at the lock position to provide a secure connection, both physical and electrical.

Thus to connect the lamp (2) to the light socket (1) the user must: a) align the twist-lock portion (14) with the corresponding lock- opening (15) by aligning lugs (14b) with slots (15b), b) insert the twist-lock portion (14) into the lock-opening (15) and thus also the bulb pins (5) into the respective conductor-opening slots (4), and c) rotate the lamp (2) and twist-lock portion (14) about the twist-lock axis (12) to effect the twist-lock connection (by rotating lugs (14b) behind periphery (15c)) and to rotate the pins (5) into electrical contact with the conducting strips (7) to provide an electrical connection therebetween.

Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope of the appended claims.

Claims

Claims:

1. A light assembly including a light socket and an electric lamp, said assembly including: a light socket including: a connection base including at least two conductor-openings adapted to receive two conducting protrusions on the lamp, each conductor-opening including therein at least one electrically conductive portion adapted to contact the protrusions and provide an electrical connection therebetween, and a lock-opening having a lock portion and an open portion which are respectively connected to the connection base, said open portion shaped and/or sized to allow for passage of a locking protrusion on a connection base of said lamp, the lock portion of the lock-opening shaped and/or sized to retain the locking protrusion therein (lock position) until the locking protusion is moved to the open portion (detach position); and a lamp including: an electric light source for emitting light,

- a connection base including two conductive protrusions for passing electricity to said light source, each protrusion configured to engage with the socket conductor-opening and conducting portion therein, and

- a locking-protrusion on said lamp connection base shaped and/or sized for:

(a) insertion into the open portion of the socket lock-opening; and

(b) movement into the lock portion only after insertion into said open portion, the locking protrusion, lock-opening and conductor-openings being respectively configured to allow relative movement of the lamp connection base with respect to the socket connection base to effect the attachment and removal of the lamp from the socket via the lock-opening.

2. A light assembly as claimed in claim 1 wherein the socket connection base and lamp base is made from a non-conductive material.

3. A light assembly as claimed in claim 1 wherein said lamp conducting protrusions are formed as pins or the like.

4. A light assembly as claimed in claim 1 wherein said socket conductor-openings and conducting protrusions, are respectively, located laterally to said socket lock- opening and lamp locking-protrusion.

5. A light assembly as claimed in claim 1 wherein said socket lock-opening and lamp locking-protrusion are located substantially centrally on the respective socket connection base and lamp base.

6. A light assembly as claimed in claim 1 wherein the conductive portion is configured to maintain electrical contact with said lamp conducting protrusions during said relative movement.

7. A light assembly as claimed in claim 1 wherein said socket conducting portions are releasably attached to said conductor-openings to facilitate easy removal and replacement.

8. A light assembly as claimed in claim 1 wherein the conductor-openings and conducting portions are configured such that the pins may only contact said conducting portions upon movement of said locking protrusion from said detach position to said lock position.

9. A light assembly as claimed in claim 1 wherein said conducting portions are formed as elongate conducting members attached at a first end to a first side of the conductor-opening and biased toward a second side substantially opposing said first side at, or proximal, a distal end thereof.

10. A light assembly as claimed in the preceding claim wherein the biased conducting portions also provide a frictional connection with said pins.

11. A light assembly as claimed in claim 9 wherein said elongate conducting member distal end is attached to said conductor-opening second side, or a portion proximal thereto.

12. A light assembly as claimed in claim 1 wherein at least one said conductor- opening includes two said conducting members on opposing sides of said conductor-opening.

13. A light assembly as claimed in claim 1 wherein said relative movement is between: a detach position wherein the locking protrusion is in said open portion, and - a lock position wherein said locking protrusion is retained in said lock portion.

14. A light assembly as claimed in claim 1 wherein the lock opening is configured to receive a locking protrusion in the form of a twist-lock portion, said lock-opening configured to only allow the insertion of the twist-lock portion when substantially aligned with same, and whereupon insertion of the aligned twist-lock portion through said open portion and subsequent rotation of the lamp base about a twist- lock axis moves the twist-lock portion into the lock-opening lock portion to thus effect a reversible twist-lock connection.

15. A light assembly as claimed in claim 14 wherein the twist-lock portion is substantially T-shaped.

16. A light assembly as claimed in claim 14 wherein said socket is configured to constrain the degree of rotational movement of said bulb once the twist-lock portion is inserted into the open portion of the lock-opening.

17. A light assembly as claimed in any one of claims 14-16 wherein said rotational movement is constrained between:

- the detach position, wherein the arms of the twist-lock portion are substantially aligned with the open portion, and

- the lock position, wherein the twist-lock portion is in the lock portion and not aligned with said lock-opening.

18. A light socket for connecting an electric lamp thereto, the light socket including: a connection base including at least two conductor-openings adapted to receive two conducting protrusions on the lamp, each conductor-opening including therein at least one electrically conductive portion adapted to contact the protrusions and provide an electrical connection therebetween, and characterised in that said socket includes: a lock-opening having a lock portion and an open portion which are respectively connected to one another, said open portion shaped and/or sized to allow for passage of a locking protrusion on a connection base of said lamp, the lock portion of the lock-opening shaped and/or sized to retain the locking protrusion therein (lock position) until the locking protrusion is moved to the open portion (detach position); the locking-protrusion, lock-opening and conductor-openings being respectively configured to allow relative movement of the lamp connection base with respect to the socket connection base to effect the attachment and removal of the lamp from the socket via the lock-opening.

19. A light assembly as claimed in claim 1 wherein the socket is further characterised in that the electrically conductive portion is adapted to be capable of contacting said conducting protrusions when the locking protrusion is located in the lock portion.

20. An electric lamp for connection to a light socket, the lamp including;

- an electric light source for emitting light, a connection base including two conductive protrusions for passing electricity to said light source, each protrusion configured to engage with a socket conductor-opening and conducting portion therein, and characterised by the further inclusion of a locking protrusion shaped and/or sized for insertion into an open portion of a socket lock-opening and for movement into a lock portion of the lock opening only after insertion of the lock protrusion into said open portion.

21. A method of reversibly connecting an electric lamp as aforementioned to a light socket as aforementioned, said method including the steps of:

- aligning the locking-protrusion on the lamp connection base with the corresponding lock-opening open portion on the light socket,

- inserting the locking-protrusion through said open portion and the lamp conducting protrusions into the respective socket conductor-openings, and moving the locking-protrusion from said open portion into said lock portion to effect the reversible attachment of the lamp to the socket.