[0001] The invention concerns a pin coupling for locking the connection between a male connector
and a female connector of a coaxial cable.
[0002] When it is necessary to obtain a permanent connection between a male connector and
a female connector of a coaxial cable, it is advisable to ensure the locking between
said connectors through special kinds of couplings, substantially consisting of two
caps, a male cap and a female cap which are joined together in order to ensure not
only the connection between them, but also the connection between the male and female
connectors which are inside said caps.
[0003] According to patent DE 40 15 092 a pin coupling is known, which has a male cap and
a female cap connecting them together through a projecting part on the male cap and
a corresponding notch on the female cap. The connection between the two co-axial cables
and consequently between the two male and female connectors and the caps takes place
in two phases. First a connector is joined to the other one so that the male cap realizes
a first locking between the male connector and the female connector. Then the female
cap is closed through an axial translation movement on the male cap by means of the
snap tightening of the notch on the projecting part previously described.
[0004] A pin coupling of the now described type presents some limits of its functionality,
due to the fact that the connecting and closing movements of the coupling takes place
in two phases and, above all, because it is necessary to operate first by pushing
the male connector and the female connector one against the other and then by pushing
on the side of the female connector. It is evident that with the now described coupling
the operator has to perform two different actions in a sequence.
[0005] The main purpose of the present invention is that of overcoming the inconveniences
previously mentioned.
[0006] The first purpose is to realize a pin coupling such that the connection between the
male connector and the female connector and the locking of the female cap on the male
cap will occur by pushing the cable from one side only or by operating on the cap
from one side only.
[0007] Another purpose of the present invention is to obtain a pin coupling with watertight
characteristics, in order to prevent the water from damaging or altering the connection
of the co-axial cable. This aspect is particularly interesting, especially if the
seal is realized in pin couplings which are used for connecting cables of car radio
antennas. In that case, in fact, the pin couplings are exposed to bad weather and,
therefore, it is important to realize a good watertight seal.
[0008] All the purposes previously mentioned and others which will be better pointed out
hereinafter, are reached by a pin coupling for locking the connection between a male
connector and a female connector connecting co-axial cables, comprising:
- a male cap holding in its inside the male or female connector of a co-axial cable,
whose plug or socket, respectively, carries a high-frequency electrical signal;
- a female cap within which the female or male connector of a second coaxial cable to
be connected to the first one is inserted, the socket or plug of said cable connecting
with the plug or socket, respectively, of said male or female connector, wherein said
pin coupling is characterized in that said male cap and said female cap lock in the
closed position of their connection through the snapping action of holding means belonging
to each cap, and co-operating with two annular projecting parts being present on the
outer metal screen belonging to the female or male connector lodging inside the female
cap.
[0009] Further characteristics and scope of applicability of the present invention will
become apparent from the detailed description given hereinafter. However, it should
be understood that the detailed description and specific examples, while indicating
three preferred embodiments of the invention, are given by way of illustration only,
since various changes and modifications within the spirit and scope of the invention
will become apparent to those skilled in the art from this detailed description and
from the drawings, wherein:
- Fig. 1 is a section of a first embodiment of the invention, represented when the female
cap is not yet locked on the male cap;
- Fig. 2 shows the pin coupling of Fig. 1 when the female cap is locked on the male
cap;
- Fig. 3 shows a cross-section of a different embodiment of the pin coupling of the
Figs. 1 and 2;
- Fig. 4 shows the pin coupling of Fig. 3 when the female cap is locked on the male
cap;
- Fig. 5 shows a cross-section of another different embodiment of the pin coupling according
to the invention.
[0010] With reference to the mentioned Figs., it can be observed that the co-axial cable,
indicated with 1, is connected to a male connector, indicated as a whole with 2, which
presents a central conductor 3 receiving the signal and which is separated from the
outside metal screen 5 through an insulating material 4. Said outside metal screen
5 extends until the rim indicated with 5a and presents also and elastic element 5b
suited to ensure the contact with the corresponding metallic screening of the female
connector, to which is connected and which is indicated as a whole with 6. Said female
connector, connected to the co-axial cable 15, presents a female contact 7 within
which the male contact 3 of the male connector 2 is then coupled. Such a female contact
7 is separated from the outside metal screen, indicated as a whole with 9, through
an insulating material 8. Such a metal screen extends to the terminal part 9a projecting
toward the coupling and it presents two annular projecting parts 9b and 9c, placed
at such a distance that, as it will be observed hereinafter, they cooperate with the
holding means belonging to the male cap 10 and the female cap 16 respectively of the
pin coupling according to the invention.
[0011] The male cap, indicated as a whole with 10, is inserted in the female connector 2.
Such a male cap, made of plastic material, locks itself on the connector lodging the
same, through a projecting part 11 being present on the inner surface of said male
cap, since such a projecting part 11 positions itself on a corresponding groove 111
obtained by performing a shrinking of the outside diameter of the metal screen 5.
The outer profile of the terminal part of the male cap 10 has the shape of a truncated-cone,
as indicated in 12. Internally, in correspondence of said truncated-conic shape part
12, the male cap presents a flared connecting surface, indicated with 13, which precedes
an annular recess 14 on which the projecting part 9b, belonging to the outside metal
screen 9 of the female connector 6, positions itself when the coupling of the male
cap 10 on the connector 12 is performed. This happens because part 12 in the shape
of a truncated-cone of the male cap has such a shape and thickness that the characteristics
of elasticity of its plastic material are enhanced. Preferably, such a part 12 in
the shape of a truncated-cone consists of sectors obtained through two or more longitudinal
cuts. Moreover, near the projecting part 11 there is a slight annular relief 101 which
ensures the water tightness between the male cap 10 and the male connector 2.
[0012] The female cap, indicated as a whole with 16, which is also preferably made of plastic
material, presents an opening 17 with a wider diameter as compared to the opposite
part which ends with a cylindrical element 18. The profile of said female cap is initially
cylindrical and then it continues with a conic section 17a which will then couple
with the corresponding conic section 12 of the male cap 10. The conic section 17a
is followed by a cylindrical section 17b which ends with another cylindrical element
18 having a smaller diameter. Said cylindrical element 18 presents, in correspondence
with the rims, two internal annular projections 19 and 20 having such a diameter that
they slidingly receive the metal screen 9 of the female connector 6.
[0013] The electric contact between the two male and female connectors 2 and 6 and the locking
of the pin coupling consisting of the male cap 10 and the female cap 16, occur by
pushing the cable 15 against the co-axial cable 1, after the connector 2 and the cap
10 have been assembled on cable 1, and after the connector 6 and the female cap 16
have been assembled on cable 15. By pushing the female connector 6 against the male
connector 2, the male cap 10 couples with the female connector 9 through the coupling
which is obtained between the annular recess 14 of the male cap 10 and the projecting
part 9b belonging to the connector 6. If the pushing of the female cap 16 against
the male cap 10 is carried further, the internal annular projection 19 of the cylindrical
element 18 goes past the projecting part 9c so that said projecting part remains inside
the cylindrical element 18 between the internal annular projections 19 and 20, as
can be observed in Fig. 2.
[0014] In other words, the internal annular projection 19, having gone beyond the projecting
part 9c, keeps the female cap 16 locked on the male cap 10. This action is helped
by the fact that the cylindrical element 18 is made of plastic material of low thickness
and consequently the element 18 has enough elasticity.
[0015] Thus the locking of the pin coupling which consists of the male cap 10 and the female
cap 16 has been obtained in the two projecting parts 9b and 9c, both of them belonging
to the female connector 6.
[0016] As an improvement of said locking between the male cap and the female cap, it can
be observed that the internal annular projection 20 has an internal diameter such
as to ensure the water sealing between the female cap 16 and the female connector
6. Another slight annular relief 171 on the female cap or on the male cap, obtains
the water sealing between the male cap 10 and the female cap 6.
[0017] From what has been described it becomes apparent that the locking of the pin coupling
occurs because of the simple sliding of the female cap 16 on the cap 10.
[0018] According to a different embodiment of the female cap, now indicated as a whole with
20 in Fig. 3, such a female cap, on the side that couples with the male cap 10, presents
an opening with a profile 21, having an essentially truncated-conic shape, with a
wider diameter on the coupling side.
[0019] From the opposite side, said female cap presents an essentially cylindrical section,
indicated with 22, presenting a flared rim 23 ending with an undercut 23a. On the
opposite side of said enlarged opening, the cylindrical section 22 presents an annular
tailpiece with a conic shape profile 24, whose smaller diameter contrasts with the
metallic surface of screen 9 belonging to the female connector 6.
[0020] Such an annular tailpiece 24 contrasting with the surface 9, realizes the seal between
said cap and said metallic surface. As a completion of the seal, it can be observed
that in the first section of the opening of the internal surface 20 there is also
a slight annular relief 25 which ensures the seal between the female cap 20 and the
outer surface of the male cap 10.
[0021] Before the female cap 20 locks itself on the male cap 10, the projecting part 9c
of the female connector 6 is comprised between the flared rim 23a and the annular
tailpiece with a conic shape profile 24.
[0022] When the female cap 20 is locked on the male cap 10, the projecting part 9c goes
past the undercut 23a and positions itself on the flared rim 23.
[0023] The passage of the projecting part 9c from the position illustrated in Fig. 3 to
the position in Fig. 4 is made possible by the elasticity of the plastic material
which is preferably increased with the help of longitudinal cuts which divide the
section 22 of the female cap into sectors.
[0024] Fig. 5 represents yet another embodiment of the invention concerning a different
type of seal obtained through an OR sealing ring which guarantees the waterproof sealing
by means of an OR ring inserted between the two metal screens of the two male and
female connectors 2 and 6 which match each other.
[0025] In order to obtain this according to the embodiment illustrated in Fig. 5, on the
inner rim of the metal screen 5 of the male connector 2, a lodging, indicated with
26, for the accommodation of the OR ring is obtained, wherein said lodging is defined
by the shrinking 51 of the inner diameter of the metal screen 5 on one side and on
the bent section 52 of rim 5a of said metal screen on the other side.
[0026] The lodging for the OR ring can also be obtained with solutions differing from the
one represented in Fig. 5, provided that said OR ring is lodged between the outer
metal screens of the two male and female connectors.
[0027] With regard to the pin coupling, the same can be obtained both by the male cap 10
in combination with the female cap 20, as can be observed in Fig. 5, and by the male
cap 10 in combination with the female cap 16, represented in the Figs. 1 and 2.
1. A pin coupling for locking the connection between a male connector (2) and a female
connector (6) connecting co-axial cables (1, 15), comprising:
- a male cap (10) holding in its inside the male or female connector (2, 6) of a co-axial
cable, whose plug or socket, (3, 7) respectively, carries a high-frequence electrical
signal;
- a female cap (16, 20) within which the female or male connector (6, 2) of a second
co-axial cable (15) to be connected to the first one (1) is inserted, the socket or
plug of said cable connecting with the plug or socket, respectively, of said male
or female connector, characterized in that said male cap (10) and said female cap (16, 20) lock in the closed position of their
connection through the snapping action of holding means belonging to each cap, and
co-operating with two annular projecting parts (9b, 9c) being present on the outer
metal screen belonging to the female or male connector (6, 2) lodging inside the female
cap (16, 20).
2. A pin coupling according to claim 1, characterized in that the male cap (10) locks on the connector (2) which lodges it through the coupling
of a projecting part (11) found on the inner surface of said male cap (10), said projecting
part positioning itself into a corresponding annular recess (111) which is present
on the outer surface (5) of said male connector, through an axial relative movement
between said cap (10) and said connector (2).
3. A pin coupling according to any of the previous claims, characterized in that the terminal part (12) of the male cap (2) has a profile in the shape of a truncated-cone
and presents a flared connecting surface (13) between the rim of the hole and the
annular recess (14), said terminal part being elastic enough to receive in its annular
recess (14) the annular projecting part (9b) belonging to the female or male connector
(6, 2).
4. A pin coupling according to claim 1, characterized in that the female cap (16) presents a section of its inner surface in the shape of a truncated-cone
profile (17a), such to match a corresponding connecting conic profile (12) being present
on the outer surface of the male cap.
5. A pin coupling according to any of the previous claims, characterized in that the female cap (16), on the side which matches the male cap (10), presents an opening
(17) having a wider diameter as compared to the opposite side which ends with an elastic
cylindrical element (18) having in correspondence with each of the two rims, an annular
inner projection (19, 20) and such a diameter as to slidingly receive the projecting
part (9c) of the metal screen (9) belonging to the connector inserted in said female
cap, the portion of said cylindrical element (18) being comprised between the two
annular projections (19, 20), lodging one of said annular projection parts (9c) when
said female cap (16) locks on the male cap (10).
6. A pin coupling according to claim 5, characterized in that one the annular inner projections (20) of the cylindrical element (18) belonging
to the female cap (16), has a diameter such as to obtain the waterproof sealing in
relation to the metal surface of the screen belonging to the connector inserted in
the same.
7. A pin coupling according to claim 5 or 6, characterized in that the female cap (16), in correspondence with the side presenting the opening with
a wider diameter, presents an annular projecting part (171) suited to obtain the waterproof
sealing on the outer surface of the male cap.
8. A pin coupling according to any of the claims from 1 to 4, characterized in that the female cap (20) presents, on the side matching the male cap, an opening with
a profile (21) presenting an essentially truncated-conic shape with a wider diameter
on the coupling side, and on the opposite side, it presents an essentially cylindrical
section (22) with a flared opening (23) within which one of the two annular projecting
parts (9c) lodges, said projecting parts being found on the metal screen belonging
to the connector inserted in said female cap, before the male cap and the female cap
are locked into one another, said cylindrical section presenting, on the opposite
side of the flared opening (23), an annular tailpiece with a conic profile (24) contrasting
with the metal surface (9) of the screen belonging to the connector (6) inserted in
said female cap (20), such as to obtain the waterproof sealing between said female
cap and said metal surface.
9. A pin coupling according to claim 8, characterized in that the female cap (20) presents, in correspondence with the side of the opening with
a wider diameter, an annular projecting part (25) suited to obtain the waterproof
sealing on the outer surface of the male cap (10).
10. A pin coupling according to any of the previous claims, characterized in that between the male connector (2) and the female connector (6) an OR sealing ring (26)is
inserted to prevent the water from entering.
11. A pin coupling according to claim 10, characterized in that the connector (2), which lodges in its interior the other connector (6) matching
the same, presents on the inner rim of the metal screen (5) a lodging for an OR sealing
ring (52), said lodging being defined by a shrinking (51) of the inner diameter of
the metal screen (5) on one side, and by the bent edge (52) of the rim of said metal
screen on the other side, the OR ring (26) ensuring the waterproof sealing protection
of the electric contact realized by junction of the two contacts.