[0001] The present invention relates to a front plate for a socket, such as a socket for
receiving a plug of an electrical cable or the like.
[0002] Though the present invention is more widely applicable, it takes its starting point
in electrical outlets comprising sockets. Electrical outlets with sockets come in
many different variations, and the term is here to be construed in the broadest sense,
covering
inter alia electrical mains outlets, outlets for telephones and telecommunications, television,
radio, audio etc. mounted in or on walls, cable conduits and the like as well as part
of switch cabinets.
[0003] Electrical outlets for some applications, and thus the sockets comprised therein
are more prone to malfunction due to contamination with moist and dirt than others.
This is in particular the case when the outlet is for small signal purposes, i.e.
with low voltage and current, such as telecommunication outlets. It is, however, also
the case for mains outlets in humid and moist conditions, e.g. in wet rooms and outdoors.
[0004] In these cases there is a desire to protect the socket against such contamination
when not in use, i.e. when no plug is inserted in the socket. In this respect, it
has been suggested to cover the socket with a front cover comprising a lid.
US-B-7651346 discloses a socket with a front cover comprising a lid. The lid is slideable with
respect to an aperture in the front cover so as to allow access to the socket behind
the front plate, and insertion of a plug therein. The lid is biased towards a position
where it covers the aperture, i.e. automatically returning the lid to the closed position
protecting the socket, when a plug is removed from the socket.
[0005] One problem identified in the prior art front covers with slidable lids is that the
minimum size of the cover is restricted by the fact that sufficient space has to be
allotted to the lid and return mechanism behind the front cover, so as to allow the
lid to occupy both the open and the closed positions.
[0006] Front covers with hinged lids are also known, be it hinged to swing outward or hinged
to swing inward with respect to the front cover. The latter suffer for the drawback
that plenty of space is required in front of the socket to accommodate the swinging
motion, whereas the former suffer from the drawback that they require two hands for
inserting the plug, i.e. one for opening and holding the lid and the other for insertion
of the plug.
[0007] It is the object of the present invention to overcome at least these problems with
the prior art.
[0008] According to the present invention, this object is achieved by a front plate for
a socket, said front plate comprising a front surface having at least one first plane
surface part and at least one aperture through which a plug may be inserted into said
socket, at least one lid adapted to close said aperture when no plug is inserted in
the socket, said lid being adapted to perform a sliding motion between a first position
where said aperture is closed and a second position where said aperture is open so
as to allow insertion of the plug, characterized in that said sliding motion is a
non-linear sliding motion between said first position and said second position, the
lid being, in the second position, located in front of and overlapping said front
surface.
[0009] Making the sliding motion non-linear allows the lid to move from a flush and well
protected resting position where it protects the socket, to an extended position in
front of and overlapping the front surface allowing the plug to be inserted. In fact
the lid may even be allowed to move partially beyond the front surface, thus allowing
for a very small front area of the front surface.
[0010] According to a preferred embodiment, the lid comprises a substantially plane surface,
said substantially plane surface being, in the first position, parallel to, and preferably
flush with, said at least one plane surface part. This allows the lid to occupy a
well protected yet easily accessible first position, which moreover does not take
up much height.
[0011] According to a further preferred embodiment, said aperture is located in the bottom
of a recess in the front surface for accommodating the lid in the first position,
said recess having guide means adapted for guiding the lid through said non-linear
motion. This allows for easy guidance of the lid through the non-linear motion whilst
still keeping the overall height low.
[0012] According to a further preferred embodiment biasing means are provided for the at
least one lid, so as to automatically return the at least one lid to said first position
when no plug is inserted in the socket. This is advantageous in that no attention
need be given to the closing of the lid when removing a plug from the socket. Instead,
the lid automatically closes and protects the socket against dirt humidity and other
pollution.
[0013] According to another preferred embodiment, the front plate further comprises side
walls arranged at an angle with respect to said front surface, where at least one
of said side walls comprises an opening adapted for insertion of said biasing means.
This allows for easy insertion of the biasing means during initial assembly as well
as for replacement purposes.
[0014] According to yet a further preferred embodiment, the biasing means comprise an omega-shaped
spring. The use of an omega-shaped spring is advantageous in that it is flat, extending
in one plane only and thus allows for a low height of the front plate. Moreover it
may readily be held in position by appropriate configuration of the lid and the internal
walls of the front plate.
[0015] According to yet another preferred embodiment, the lid comprises a protrusion extending
from said substantially plane surface. This allows for engagement with the plug to
be inserted, by means of a single-handed movement of the lid into the open second
position using the plug only.
[0016] According to a further preferred embodiment, the protrusion comprises a wall with
a centrally recessed top wall part. Recessing the top wall part is particularly advantageous
because it provides easy access of possible locking means of the plug which may need
to be released before removal of the plug.
[0017] The invention will now be described in greater detail based on non-limiting exemplary
embodiments in conjunction with the appended drawings, on which:
Fig. 1 shows a front perspective view of the front plate according to the invention
with two lids, one lid slightly open and one lid in a open position,
Fig. 2 shows a front perspective view of the front plate of Fig. 1 with one lid removed
and one lid partially open,
Fig. 3 shows a front perspective view of the front plate of Fig. 1 with both lids
closed,
Fig. 4 shows a cross-section of the front plate taken along the line IV-IV of Fig.
2,
Fig. 5 shows a plan view of the rear side of the front plate of Fig. 1,
Fig. 6 shows a perspective front view of the lid, and
Fig. 7 shows a perspective rear view of the lid.
[0018] In Fig. 1 a cover plate 1 according to the invention is shown. The cover plate of
Fig. 1 is adapted for mounting as the closing member of a box comprising the at least
one socket, such as a wall mounted installation box, a cable guide or the like, and
has means 5 for engaging such a box. The cover plate 1 furthermore comprises an optional
window 6 for e.g. presenting information about the connections related to the socket.
The window 6 is optional, and it is evident for the skilled person that the omission
thereof would further reduce the front area of the cover plate 1.
[0019] As can be seen, in Fig. 1, the cover plate 1 comprises a front surface with at least
one first plane surface part 2 but may have further plane surface parts such as a
plane surface part 3 surrounding the first plane surface part 2. In the front surface
two apertures 4 through which a respective plug may be inserted into a matching socket
are provided. Neither the plugs nor the sockets are shown, as the actual type of matching
plugs and sockets are of minor importance for the invention. The outset of the present
invention, however, is data cables with RJ45 plugs and sockets, but the invention
is applicable to numerous other plug and socket connections, such as USB and other
data cables, electrical mains, optical cables, etc.
[0020] As indicated above, the cover plate 1 comprises two slidable lids 7 adapted to cover
a respective aperture 4. In Fig. 1, the lid 7 on the right-hand side has been slid
in front of the front surface so as to uncover the aperture 4, whereas he lid 7 on
the left-hand side is located in an intermediate position in front of an aperture
4 so as to almost cover it. It will be understood that the arrangements of the respective
lids 7 and the apertures 4 of Fig. 1 are essentially identical to each other. It will
thus be appreciated that the lids 7 on both the right-hand side and the left-hand
side are accommodated in respective recesses 8 in the bottom of which the apertures
4 are located. Preferably the lid 7 is accommodated in such a way in the recess 8
that the front surface is flush with or at least parallel with the first plane surface
2, when in the closed position, as illustrated in Fig. 3.
[0021] Each lid 7 is a rigid, preferably integral piece, made by an appropriate manufacturing
method, such as injection molded in one piece from a suitable thermoplastic material,
e.g. ABS. At one end the lids 7 comprise a protrusion 9 for engagement by a plug to
be inserted or by a finger, in order to slide the lid 7 from a first position accommodated
in the recess 8 as depicted in Fig. 3 to a second position corresponding to the position
depicted on the right-hand side of front cover 1 of Fig. 1. Preferably the protrusion
9 is a raised wall part serving as an engagement means for a plug to be inserted.
Preferably, the raised wall part has a centrally arranged cut-out or a recess 10 allowing
for easy access to the locking tab of a plug, such as the locking tab of an RJ45 plug,
when the plug is to be removed from the socket.
[0022] As will be explained in greater detail below, the lids 7 are biased to return automatically
to the first position illustrated in Fig 3, where they are accommodated in the recess
8. Thus, to insert a plug, the plug is brought into proximity of the front surface
2, then slid along the front surface into engagement with the protrusion 9. Then through
a further sliding motion the plug moves the lid 7 from the first position as depicted
in Fig. 3 to the second position depicted on the right-hand side of the front cover
of Fig. 1, thus uncovering the aperture 4 and allowing for insertion of the plug perpendicular
to the front surface 2.
[0023] Turning now to Fig. 5, the biasing means will be explained. Fig. 5 is a rear plan
view of the front cover 1 with both lids 7 in the closed position, i.e. as shown in
Fig. 3. The rear sides of both the lids 7 are partially visible through the apertures
4. Also partially visible is the biasing means 11 for biasing the lids towards the
first position which they both occupy in Fig. 5. As will be explained below, the biasing
means 11 on the right-hand side of Fig. 5, is in the mounted position, whereas the
biasing means 11 on the left-hand side is in a position found only during insertion.
[0024] The biasing means 11 is preferably a flat spring so as to allow the overall height
of the front cover 1 to be kept low. In the preferred embodiment the illustrated biasing
means 11 is a generally omega-shaped steel spring with two legs, adapted to either
engage a groove formed as an undercut protruding wall part 12 on the rear side of
the lids 7, or engaging an upstanding wall part 13 of the rear of the front cover
1, as illustrated on the right-hand side of Fig. 5. Though the use of an omega-shaped
steel spring is currently preferred, the skilled person will realize that other types
of spring or biasing means 11 could be used instead. One reason that the omega-shaped
spring is currently preferred is also that it allows for easy insertion into the front
cover 1 during manufacture or in case it becomes necessary to replace the spring.
In order to easily insert the omega-shaped spring an opening in the form of a slit
14 is provided in appropriate ones of the outer side walls 15. As illustrated on the
left-hand side of Fig. 5, the omega-shaped spring may be inserted through the slit
14, into the position illustrated on the right-hand side of Fig. 5.
[0025] As indicated it is an important aspect of the present invention that the lid 7 is
movable through a non-linear motion. This allows the lid to move at least partially
in front of the front surface of the front cover 1, thus freeing the lid 7 from internal
space constraints of the front cover 1. For this purpose the recess 8 is provided
with guiding surfaces 16, 17, 18, 19, 20 (best seen in Fig. 2), of which at least
some are contiguous. In the present example the guiding surfaces 16 and 17 are not
contiguous in the sense that two surfaces 21, 22 which do not perform any function
as guiding surfaces are present. These guiding surfaces cooperate with running surfaces
23 and 24 located on the rear side of the lid 7, such as a tapered front end surface
23 and inclined end surface 24. Runner-like side walls 25 are also provided, but do
not actually engage the guiding surfaces 16, 17, 18, 19, 20 in illustrated embodiment
of the present invention. Furthermore, the lid 7 comprises a pair of lateral bosses
26 engaging and guided in corresponding lateral grooves 27 in the recess 8, thereby
preventing the lid 7 from separating from the remainder of the front cover 1 and falling
out of the recess 8.
[0026] When engaging the protrusion 9 with a plug or a finger and pressing or pulling the
lid 7 in the downward direction (in the sense of Fig. 1), the tapered front end surface
23 will, guided by the guide surface 16, easily slide over the edge of the recess
8. Upon further motion the inclined end surface 24 will move down the ramp surface
20 and onto the surface 19, forcing the tapered front surface 23 out of engagement
with the guiding surfaces in an outward turning motion of the lid 7 with respect to
the recess 8. Subsequently, the inclined end surface 24 will slide along the surface
19, until it reaches the next ramp surface 18, where the lid 7 will be forced to a
slight inward turning motion with respect to the recess 8. However, in the position
just before or when it reaches the next ramp surface 18, the plug may be inserted.
[0027] If it is desired to remove the plug the inclined surface 24 of the lid 7 may be moved
onto the surface 19 and further onto the surface 17, in a new turning motion of the
lid 7, allowing the lid 7 to be pressed deep down into the recess 8, so as to allow
good access to grasping the plug and disengaging possible locking means of the plug.
[0028] As will be understood the above motions provide a non-linear sliding motion, which
may moreover comprise not only a translator motion but preferably also some rotary
motion. This allows the lid 7 to move in front of the front cover into an open position
where a plug may easily be inserted as well as removed. Moreover the lid 7 will be
well protected in the first position, i.e. located in the recess 8, when no plug is
inserted.
1. A front plate for a socket, said front plate comprising
a front surface having at least one first plane surface part and at least one aperture
through which a plug may be inserted into said socket,
at least one lid adapted to close said aperture when no plug is inserted in the socket,
said lid being adapted to perform a sliding motion between a first position where
said aperture is closed and a second position where said aperture is open so as to
allow insertion of the plug,
characterized inthat
said sliding motion is a non-linear sliding motion between said first position and
said second position, the lid being, in the second position, located in front of and
overlapping said front surface.
2. A front plate according to claim 1, wherein the lid comprises a substantially plane
surface, said substantially plane surface being, in the first position, parallel to,
and preferably flush with, said at least one plane surface part.
3. A front plate according to any one of the preceding claims, wherein said aperture
is located in the bottom of a recess in the front surface for accommodating the lid
in the first position, said recess having guide means adapted for guiding the lid
through said non-linear motion.
4. A front plate according to any one of the preceding claims, wherein biasing means
are provided for the at least one lid, so as to automatically return the at least
one lid to said first position when no plug is inserted in the socket.
5. A front plate according to claim 4, further comprising side walls arranged at an angle
with respect to said front surface, where at least one of said side walls comprises
an opening adapted for insertion of said biasing means.
6. A front plate according to any one of claims 4 or 5, wherein the biasing means comprise
an omega-shaped spring.
7. A front plate according to any one of claims 2-6, wherein said lid comprises a protrusion
extending from said substantially plane surface.
8. A front plate according to claim 7, wherein said protrusion comprises a wall with
a centrally recessed top wall part.