[0001] The present invention relates to industrial sockets, and in particular to a socket
for electric vehicles provided with a live contacts protection device that is automatically
disengaged upon insertion of the corresponding plug.
[0002] It is known that the market offers sockets, both for industrial and domestic use,
provided with a contacts protection device to increase the safety level for the user
so that the latter can not accidentally come into contact with live parts. Such a
device usually consists of a cover arranged within the socket body, in the space below
the holes for the entrance of the pins, which is biased by a spring to cover the live
contacts and is moved by the corresponding plug, with a translational or rotational
motion, to gain access to the contacts (see e.g.
EP 1376772).
[0003] A socket for electric vehicles manufactured according to the IEC 62196-2 standard
(Standard Sheet 2-IIa) is however designed such that it is not possible to apply the
above-illustrated usual protection device. In fact, inside the socket body there is
no space suitable to house the cover since the corresponding plug was designed so
that it substantially takes up the whole space inside the socket body.
[0004] Therefore the object of the present invention is to provide a socket for electric
vehicles of the above-mentioned type which is however provided with a live contacts
protection device. This object is achieved by means of a socket provided with a pair
of covers arranged substantially outside the socket body and comprising terminal portions
that penetrate the socket body to cover the live contacts, said covers being moved
from said working position, to which they are biased by elastic members, to a rest
position, in which their terminal portions are outside the socket body, by at least
one actuating member projecting inside the socket body and suitable to be moved outside
the socket body by the corresponding plug upon insertion of the latter into the socket.
Other advantageous features of the present industrial socket are recited in the dependent
claims.
[0005] The main advantage of the socket according to the present inventions obviously is
that of achieving the function of live contacts protection to guarantee the safety
of the user of this particular type of socket.
[0006] Another advantage of this socket, in its preferred embodiment, resides in the presence
of a mechanism for locking the protection device which prevents the latter from being
moved away from the working position when the corresponding plug is not inserted so
as to further increase the safety.
[0007] These and other advantages and characteristics of the industrial socket according
to the present invention will be clear to those skilled in the art from the following
detailed description of an embodiment thereof, with reference to the annexed drawings
wherein:
Fig.1 is a perspective exploded view from the rear bottom side of the above-mentioned socket
and of the corresponding plug;
Fig.2 is a view similar to the preceding one from the front bottom side;
Fig.3 is a view similar to the preceding one from the rear top side;
Fig.4 is a perspective view from the rear bottom side with a corner portion removed;
Fig.5 is a perspective view from the front top side with the top portion removed and an
enlarged detail;
Fig.6 is a view similar to the preceding one with a lateral portion removed and the corresponding
plug in the initial phase of insertion into the socket;
Fig.7 is a view similar to the preceding one with the plug in a phase of insertion into
the socket just after the phase of Fig.6;
Fig.8 is a side view of the socket with a lateral portion removed and an enlarged detail
showing the plug in an intermediate phase of insertion into the socket;
Fig.9 is a perspective view from the rear bottom side of the socket with a lateral portion
removed and the plug in the final phase of insertion into the socket;
Fig.10 is a see-through top plan view of the socket with the plug completely inserted; and
Fig.11 is a sectional view taken along line A-A of Fig. 10.
[0008] With reference to figures 1 to 5, there is seen that an industrial socket according
to the present invention conventionally includes a socket body 1 suitable to receive
a corresponding plug 2, inside said body 1 there being suitably arranged seven cylindrical
longitudinal housings 3 in four of which there are fitted metal sleeves 4 acting as
live contacts in which the corresponding pins of plug 2 are inserted.
[0009] A first novel aspect of the present socket is the presence on each lateral side of
body 1 of a cover 5 that is rotatably mounted outside body 1 by means of a pivot 6
passing through a bushing 5a, formed at an end of said cover 5, and secured in a longitudinal
seat 7 formed on the bottom side of a transverse flange 8 integral with body 1. Cover
5 is provided with two elongated terminal portions 5b suitable to penetrate body 1,
through corresponding slots 1a, and the adjacent cylindrical housings 3, through similar
slots not visible in the drawings, up to a position above sleeves 4 so as to prevent
access thereto.
[0010] The rotation of covers 5 around pivots 6 is caused by an actuating member that, in
the preferred embodiment illustrated in the drawings, consists of a cursor 9 located
at the rear side of body 1 towards which it is biased by a pair of coil springs 10
arranged between cursor 9 and a longitudinal wall 11 formed on the bottom side of
flange 8 and provided with suitable seats 11a (see Fig.2 and detail of Fig.8).
[0011] More specifically, cursor 9 has a pair of frontal projections 9a, suitable to penetrate
body 1 through corresponding openings 1b, whose length at the top is shorter than
the length at the bottom so as to form a slanted plane 9aa whose bottom portion 9ab
is longitudinally shaped as an arc of circle to mate with the adjacent cylindrical
housings 3. Moreover, cursor 9 has a pair of lateral projections 9b shaped to partially
enclose bushings 5a and provided with bottom pegs 9c suitable to engage corresponding
grooves 5c formed in the top side of covers 5 at an outermost position with respect
to bushings 5a, as better illustrated in the enlarged detail of Fig.5 (where the cylindrical
housings 3 are interrupted below cursor 9 and covers 5 for the sake of clarity of
the drawing).
[0012] Therefore when the contact protection device is in its working position illustrated
in figures 4 and 5, covers 5 are abutting against body 1 with their terminal portions
5b arranged above sleeves 4, while cursor 9 projects inside body 1 with its frontal
projections abutting against the adjacent cylindrical housings 3. This position of
the protection device is maintained by springs 10 compressed between cursor 9 and
wall 11, and the centripetal force on cursor 9 is transferred to covers 5 through
pegs 9c and grooves 5c as described above.
[0013] A second novel aspect of the socket according to the present invention is preferably
given by the presence of a mechanism for locking the protection device which prevents
the latter from moving away from the working position in a safer way than what is
provided by the mere resistance of springs 10. In fact although the protection device
arranged below flange 8 is enclosed by a casing (not shown), covers 5 are accessible
at the terminal portions 5b projecting into the cylindrical housings 3 when the plug
is not inserted. The presence of a specific locking mechanism allows therefore to
further increase the safety of the socket and to meet the requirements of the standards
of the sector.
[0014] This mechanism preferably consists of a lever 12 rotatably mounted outside body 1,
at the front side thereof, by means of a pair of pivots 13 passing through bushings
12a, formed at the top ends of said lever 12, and secured in transverse seats 14 formed
on the bottom side of flange 8. More specifically, lever 12 has a substantially L-shaped
section with the bottom edge shaped as an arc of circle to abut against body 1 under
the bias of a torsion spring 15, and in that position it locks covers 5 thanks to
its bottom ends 12b as shown in Fig.4 and in the detail of Fig.6. Moreover, lever
12 has a pair of rear teeth 12c suitable to project inside body 1 passing through
corresponding slots 1c.
[0015] In the light of the description above, and of figures 6 to 11, the simple and effective
operation of the industrial socket according to the present invention is readily understood.
[0016] As shown in the detail of Fig.6, as soon as plug 2 starts to be inserted in the socket
body 1 its bottom edge comes into contact with teeth 12c of the locking lever 12 which
project inside body 1 just below flange 8. Proceeding with the insertion, plug 2 rotates
lever 12 around pivots 13 by pushing teeth 12c outside body 1, whereby ends 12b move
downwards and disengage covers 5 (as shown in the detail of Fig.7).
[0017] After this initial phase of insertion, plug 2 encounters the frontal projections
9a of cursor 9 which project inside body 1 through openings 1b, and more precisely
the contact occurs at the slanted planes 9aa, as shown in the detail of Fix.8. The
push of plug 2 on the slanted planes 9aa causes cursor 9 to move back overcoming the
resistance of springs 10, and this backwards motion results in a rotation of covers
5 around pivots 6 thanks to pegs 9c engaged in grooves 5c. As a consequence, the terminal
portions 5b are pulled out of body 1 through slots 1a and the pins of plug 2 have
free access to sleeves 4, as shown in Fig.9.
[0018] The rest position of the protection device is illustrated in figures 10 and 11 that
show plug 2 completely inserted in the socket body 1, with teeth 12c and projections
9a abutting against the body of plug 2 under the bias of springs 10. This bias provides,
obviously, to restore the working position of the protection device illustrated in
figures 4 and 5 as soon as plug 2 is pulled out of the socket body 1.
[0019] It is clear that the above-described and illustrated embodiment of the socket according
to the invention is just an example susceptible of various modifications. In particular,
the shape of the covers and of their relevant actuating member can somewhat change
while remaining within the present inventive concept. For example, the translating
cursor 9 could be replaced with a rotating cursor similar to lever 12 by providing
a coupling with covers 5 that converts the rotation of the cursor around a transverse
axis into a rotation of the covers around their longitudinal axis.
[0020] As an alternative, cursor 9 could be altogether absent and plug 2 could act directly
on an actuating member consisting of terminal portions of the covers shaped with slanted
planes similar to the above-described slanted planes 9aa, possibly with the exception
of the distal portion that penetrates the cylindrical housings 3 and covers sleeves
4. In this case the covers could be mounted individually in a way similar to the above-described
cursor 9, with springs exerting a centripetal bias, while the locking mechanism consisting
of lever 12 could remain unchanged. Furthermore, the movement of the two covers could
be synchronized by connecting them so as to make the operation of the protection device
smoother.
1. A socket for electric vehicles comprising a body (1) suitable to receive a corresponding
plug (2) that substantially takes up all the space available inside said body (1),
in which there are arranged a plurality of longitudinal cylindrical housings (3) in
some of which there are fitted metal sleeves (4) acting as live contacts in which
there are inserted corresponding pins of said plug (2), characterized in that it further includes at least a pair of covers (5) arranged substantially outside
the body (1) and provided with terminal portions (5b) that penetrate the body (1)
through corresponding slots (1a) and extend inside said cylindrical housings (3) containing
said metal sleeves (4) so as to cover said live contacts, said covers (5) being moved
from said working position, to which they are biased by elastic members, to a rest
position, in which said terminal portions (5b) are outside the body (1), by at least
one actuating member projecting inside the body (1) and suitable to be moved outside
the body (1) by the plug (2) upon insertion of the latter into the socket.
2. A socket for electric vehicles according to claim 1, characterized in that it further includes a mechanism for locking the covers (5), said mechanism comprising
at least one disengagement portion projecting inside the body (1) at a position higher
than the actuating member so as to be moved outside the body (1) by the plug (2) upon
insertion of the latter into the socket and to disengage the covers (5) prior to the
plug (2) coming into contact with the actuating member.
3. A socket for electric vehicles according to claim 1 or 2, characterized in that the body (1) has a flange (8) under which there are secured the covers (5) and/or
the actuating member and/or the locking mechanism.
4. A socket for electric vehicles according to any of the preceding claims, characterized in that each cover (5) is rotatably mounted at a lateral side of the body (1) through a pivot
(6) passing through a bushing (5a), formed at an end of said cover (5), and secured
in a longitudinal seat (7), the rotation of the covers (5) around said pivots (6)
being caused by an actuating member that consists of a cursor (9) located at the rear
side of the body (1) towards which it is biased by a pair of coil springs (10) arranged
between said cursor (9) and a longitudinal wall (11) integral with the body (1), the
cursor (9) having a pair of frontal projections (9a) suitable to penetrate the body
(1) through corresponding openings (1b) and having a length at the top that is shorter
than the length at the bottom so as to form a slanted plane (9aa), as well as a pair
of lateral projections (9b) provided with bottom pegs (9c) suitable to engage corresponding
grooves (5c) formed in the top side of the covers (5) at an outermost position with
respect to the bushings (5a).
5. A socket for electric vehicles according to the preceding claim, characterized in that the bottom portion (9ab) of the slanted plane (9aa) is longitudinally shaped as an
arc of circle to mate with the adjacent cylindrical housing (3).
6. A socket for electric vehicles according to claim 4 or 5, characterized in that the lateral projections (9b) of the cursor (9) are shaped to partially enclose the
bushings (5a) of the covers (5).
7. A socket for electric vehicles according to any of claims 1 to 3, characterized in that the actuating members consist of terminal portions of the covers (5) shaped with
slanted planes, the covers being mounted for a transverse translation under the action
of bias springs biasing them towards the body (1).
8. A socket for electric vehicles according to any of the preceding claims, characterized in that the locking mechanism consists of a lever (12) rotatably mounted outside the body
(1), at the front side thereof, by means of a pair of pivots (13) passing through
bushings (12a) formed at the top ends of said lever (12) and secured in transverse
seats (14), the lever (12) being biased into abutment against the body (1) by a torsion
spring (15) in a position such as to lock the covers (5) and having a pair of rear
teeth (12c) suitable to project inside the body (1) passing through corresponding
slots (1c).