Technical Field

The present invention relates to a device for the interconnection of electrical cables.

Background Art

The devices commonly used for the interconnection of electrical cables and other elements, such as connection terminals, power sockets, and the like, have a connection body into which the elements to be connected can be inserted. Generally, the connection body is a terminal block to which are connected the various power leads contained in the corresponding electrical cables to be interconnected.

The terminal block comprises several terminals made of conductive material and adapted to secure the power leads contained inside the electrical cable.

Generally, each terminal is paired with another terminal by means of a fixed lead element.

Therefore, by connecting two different lead elements to a first and a second terminal which are part of the same pair respectively, an effective electrical connection is achieved.

In known devices, the terminal block is contained in special rigid bodies, generally of elongated shape, adapted to protect the terminal block and secure the body of the cables to be interconnected.

In fact, under traction, the power leads of the cable can easily become disconnected from the terminal, interrupting the connection and damaging the power leads themselves.

For this reason, the rigid bodies of the interconnection devices comprise cable glands adapted to secure the electrical cable inside the connection device.

The cable glands prevent the axial sliding of the electrical cable following external tensile forces due, for example, to the tensile force required to lay the cable between the elements to be connected.

Generally, known cable glands are substantially cylindrical devices provided with an electrical cable passage channel and an electrical cable clamping system. The passage channel is made with different diameters depending on the size of the electrical cable to be housed.

Cable gland clamping systems of known type have a fastening ring nut which is screwed onto the body of the cable gland and defines a truncated cone surface which, by acting on an elastically deformable body, causes it to contract in a radial direction with respect to the longitudinal axis of the elongated body of such devices.

The contraction of the elastically deformable body on the electrical cable ensures that the surface of the elastically deformable body itself adheres to the electrical cable, preventing its movement along its longitudinal axis.

Summing up, once the power leads to be interconnected to the terminal block have been secured and once the respective electrical cables have been secured inside the connection device by means of the corresponding cable glands, an elongated cylindrical structure is obtained, from the ends of which extend the electrical cables directed towards the elements to be interconnected, e.g., a beacon to be connected to the power socket connected to the main electrical system.

Known devices of this kind are widely used in industry and differ as regards the materials from which they are made and in size depending on the industry and the application requirements.

Such cable glands, however, are subject to improvements aimed at making devices which, once installed, are more manageable and which are watertight to ensure the insulation of the electrical cable connections with respect to the outside environment under conditions of greater operating safety.

More specifically, the use of known devices in port areas has some drawbacks mainly due to the shape of the device itself and to the need to obtain partial or in some cases total insulation of the terminal block from the outside environment. In fact, known devices installed to interconnect two electrical cables cause a sharp increase in volume along the electrical cables themselves forming a pronounced stepped structure.

The overall dimensions of the device make it difficult for operators in the sector to perform normal cable movement operations to connect different elements interconnected by the electrical cables.

In fact, the stepped structure easily slots into the elements which can be found along the path of the electrical cable, e.g., to the bollards for mooring vessels or more simply to other electrical cables, and therefore makes it difficult to move the electrical cables themselves and, in the worst case, damages the cables and/or the devices used with consequent risk of malfunction.

Furthermore, the fact is underlined that the devices of known type can be assembled and disassembled by the end user an unmentioned number of times, and in the case of anomalies due, for example, to the entry of water into the devices, it is not possible to understand whether such anomalies are due to the lack of water- tightness of the device attributable to the manufacturer or to any tampering due to human actions attributable to the end user.

Description of the Invention

The main aim of the present invention is to provide a device for the interconnection of electrical cables which allows simplifying the movement operations of the interconnected electrical cables, in particular making their sliding easier and reducing the possibility of interlocking, and which has a high degree of water tightness once assembled.

Another object of the present invention is to provide a device for the interconnection of electrical cables which allows detecting any possible tampering of the devices themselves due to human actions carried out after the first wiring of the electrical cables and assembly of the device, to prevent any anomalies in the electrical connections between the electric cables.

Another object of the present invention is to provide a device for the interconnection of electrical cables which allows overcoming the aforementioned drawbacks of the prior art within the scope of a simple, rational, easy, efficient to use and cost-effective solution.

The aforementioned objects are achieved by the present device for the interconnection of electrical cables having the characteristics of claim 1.

Brief Description of the Drawings

Other characteristics and advantages of the present invention will become more evident from the description of a preferred, but not exclusive embodiment of a device for the interconnection of electrical cables, illustrated by way of an indicative, but non-limiting example, in the attached drawings in which:

Figure 1 is a perspective view of the device according to the invention;

Figure 2 is an exploded view of the device according to the invention;

Figure 3 is a sectional view of the cover element of the device according to the invention;

Figure 4 is an axonometric view of a detail of the device according to the invention in a screwing configuration;

Figure 5 is an axonometric view of a detail of the device according to the invention in an unscrewing configuration;

Figures 6 and 7 are axonometric views of a detail of the device according to the invention.

Embodiments of the Invention

With particular reference to these figures, reference numeral 1 globally indicates a device for the interconnection of electrical cables.

The device 1 for the interconnection of electrical cables comprises:

at least a main element 31 made of an electrically insulating and waterproof material adapted to contain at least a terminal block element 3 for the electrical interconnection of at least two electrical cables 4 and comprising at least a first passage channel 6 of at least one electrical cable 4 and clamping means 14, 16 of the electrical cable 4 inside the first passage channel 6;

at least a cover element 18 of the main element 31 made of an electrically insulating and waterproof material, comprising at least a second passage channel 32 of at least an electrical cable 4 and hermetically coupleable to the main element 31 by activating the clamping means 14, 16 for the clamp of the electrical cable 4.

The main element 31 is of a substantially cylindrical hollow shape adapted to contain the terminal block element 3 and two electrical cables 4.

The terminal block element 3 is a rigid body comprising a set of terminals, which are combined in pairs to allow the interconnection of different power leads contained within the two electrical cables 4 to be interconnected. The cover element 18 comprises at least a head portion 33 having a first outer lateral surface 34 of substantially truncated-cone conformation, with the convex part arranged substantially opposite with respect to the main element 31.

The term 'convex' indicates the portion of the first outer lateral surface 34 inclined towards the truncated-cone restriction.

The head portion 33 also comprises an inner lateral surface 39 also of substantially truncated-cone conformation and with convexity arranged substantially on the opposite side with respect to the main element 31.

Furthermore, the cover element 18 comprises at least a central axis C which is centered along the second passage channel 32 and, with respect to the central axis C, the first outer lateral surface 34 is inclined to form a first angle 35 comprised between 5° and 60°.

Preferably, the first angle 35 of inclination of the first outer lateral surface 34 with respect to the central axis C is comprised between 5° and 25°.

Specifically, the first angle 35 is equal to 15°.

The cover element 18 also comprises a tail portion 36 associated with the head portion 33 and having a second outer lateral surface 40 of cylindrical shape with a substantially hexagonal section which is adapted to facilitate the coupling between the main element 31 and the cover element 18.

Furthermore, the cover element 18 comprises at least an auxiliary outer lateral surface 37 interposed between the first outer lateral surface 34 and the second outer lateral surface 40.

The auxiliary outer lateral surface 37 is inclined with respect to the central axis C to form a second angle 38 comprised between 5° and 60°.

Preferably, the second angle 38 of inclination of the auxiliary outer lateral surface 37 with respect to the central axis C is comprised between 12° and 32°. Specifically, the second angle 38 is equal to 22°.

Advantageously, the second angle 38 is made larger than the first angle 35. This way, with particular reference to Figure 3, the result of the joining of the first outer lateral surface 34 to the auxiliary outer lateral surface 37 is an outer profile of the head portion 33 substantially funnel-shaped, the inclination of which with respect to the central axis C increases in passing from the first angle 35 to the second angle 38.

The term 'profile' indicates the section of the device 1 along a plane passing through the central axis C.

Alternative embodiments cannot however be ruled out wherein there are further auxiliary outer lateral surfaces 37 arranged in succession to each other to increase gradually the inclination of the head portion 33 of the cover element 18.

Moreover, the auxiliary outer lateral surface 37 joins the second outer lateral surface 40 of the tail portion 36, the profile of which is substantially parallel to the central axis C.

In particular, the cross-section of the tail portion 36 of the cover element 18 is substantially identical to the cross- section of the main element 31.

The cover element 18 is made of a material of the type selected from the following list: plastic technopolymer, thermoplastic rubber and silicone.

More specifically, the selected materials are resistant to crushing, electrically insulating and slipping adapted to facilitate the handling of the connected electrical cables 4 thanks to the use of the invention.

The tail portion 36 comprises first coupling means 19 and the main element 31 comprises at least a pair of first extreme portions 12 opposed to each other. Each first extreme portion 12 is provided with a plurality of elastically yielding flanges 14, defining in part the clamping means 14, 16, and with second coupling means 15 complementary to the first coupling means 19 to hermetically couple the cover element 18 to the main element 31.

The clamping means 14, 16 comprise at least an elastically deformable reducer element 16 arranged inside the first passage channel 6 at the flanges 14.

The reducer element 16 is adapted to operate in conjunction with the flanges 14, to hermetically clamp the first passage channel 6.

More specifically, the reducer element 16 is a hollow cylinder adapted to be crossed by the electrical cable 4 and is made of a thermoplastic elastomeric material, e.g., of the SEBS-TPEV type.

Alternative embodiments cannot however be ruled out wherein the reducer element 16 comprises a pair of cylinders concentric to one another and which can be used at the same time to compensate for the difference in diameter between the first passage channel 6 and the electrical cable 4, so as to adequately clamp the first passage channel 6.

The main element 31 comprises:

- at least a pair of intermediate bodies 5, each of which comprises the first extreme portion 12, a second extreme portion 11, opposed to the first extreme portion 12 and provided with third coupling means 13, and with a first abutment surface 7a; and

at least a container body 2 adapted to contain the terminal block element 3 and comprising at least a pair of third extreme portions 9, each of which is provided with fourth coupling means 10 complementary to the third coupling means 13 and with a second abutment surface 7b complementary to the first abutment surface 7a, to the third and fourth coupling means 10 being coupleable to hermetically couple the intermediate body 5 to the container body 2 in a coupling configuration in which the first and second abutment surfaces 7a, 7b are in contact with each other.

Advantageously, the device 1 also comprises elastically deformable gasket means 8 which are arranged at at least one of the second extreme portion 11 and the third extreme portion 9, the gasket means 8 being in contact with the first abutment surface 7a and the second abutment surface 7b in the coupling configuration to hermetically couple the intermediate body 5 to the container body 2.

Specifically, the gasket means 8 are made of an electrically insulating polymeric material.

The cover element 18 associated with the main element 31 defines an assembly configuration in which:

the electrical cable 4 is coupled at least partly to the terminal block element 3, passes through the first passage channel 6 and the second passage channel 32 and is hermetically clamped by the clamping means 14, 16; and - the first coupling means 19 are coupled to the second coupling means 15, the cover element 18 is hermetically coupled to the main element 31 and the first passage channel 6 and the second passage channel 32 substantially match and are centered along the central axis C; and

the flanges 14 are fitted inside the cover element 18 and are bent by the inner lateral surface 39 of the tail portion 36 to press on the reducer element 16, which hermetically adheres to the electrical cable 4 and to the cover element 18 to clamp hermetically the second passage channel 32.

Furthermore, in the assembly configuration, the device 1 is hermetically sealed to guarantee IP68 certification.

Advantageously, the device 1 is provided with at least a breaking screw 41 which is adapted to clamp the electrical cables 4 inside the terminal block element 3.

The breaking screw 41 comprises:

at least a threaded stem 42 of elongated shape, screwable inside the terminal block element 3 and provided with a locking end 43 adapted to clamp the electrical cable 4 inside the terminal block element 3;

- at least a screwing head 45 associated with the threaded stem 42 by interposition of a programmed breakage weakened portion 44 when a predetermined torque value applied to the breaking screw 41 is exceeded, the screwing head 45 being separated from the threaded stem 42 at the same time of the breakage of the weakened portion 44.

Specifically, the weakened portion 44 is a portion of the breaking screw 41 the cross-section of which has a smaller radius than that of the threaded stem 42 and the screwing head 45.

In fact, since the radius of the cross-section of the breaking screw 41 is directly proportionate to its resistance to torsion, the weakened portion 44 has a lower resistance to torsion than that of the threaded stem 42 and the screwing head 45. Consequently, when a torque value greater than a preset value is applied to the screwing head 45, the breaking screw 41 breaks at the weakened portion 44. More specifically, in the assembly configuration, the electrical cables 4 are interconnected through their respective leads which are blocked by the locking ends 43 of the breaking screws 41 screwed up inside the corresponding terminals of the terminal block element 3.

In fact, the electrical cables 4 extend from the terminal block element 3 located inside the device 1 until they exit through the head portion 33 from the cover element 18.

Furthermore, once the electrical interconnection between the electrical cables 4 has been established, it is possible to apply a preset torsional value to the screwing head 45 such as to break the breaking screw 41 at the weakened portion 44.

This way, it is no longer possible to unscrew the threaded stem 42 which remains inserted inside the terminal block element and separate from the screwing head 45 to prevent tampering with the electrical connection of the electrical cables 4.

The device 1 comprises tampering detection means 20 provided with at least a breakable portion 21 adapted to break at the same time of a first decoupling of the intermediate body 5 and the container body 2 from the coupling configuration.

The tampering detection means 20 comprise:

at least a stop element 21 provided with at least a stop surface 22, the stop element 21 being coincident with the breakable portion 21;

at least a counter- stop element 23 provided with at least a first counter- stop surface 24 and a second counter-stop surface 25 which is substantially opposed to the first counter-stop surface 24, the stop element 21 and the counter- stop element 23 defining a ratchet mechanism in which the stop surface 22 is adapted to glide onto at least one of the first and second counter- stop surfaces 24, 25.

Within the scope of this treatise, the term ratchet mechanism refers to the particular mechanism wherein the first counter-stop surface 24 allows the movement of the stop element 21 with respect to the counter- stop element 23 in a first direction of rotation, in turn hindering the movement of the stop element 21 with respect to the counter- stop element 23 in a second direction of rotation opposite the first direction of rotation, unless the stop element 21 breaks due to the force exerted by the stop surface 22 on the first counter-stop surface 24.

Moreover, the tampering detection means 20 comprise a plurality of stop elements 21 and a plurality of counter- stop elements 23. Specifically, the space between the first counter- stop surface 24 of one of the counter-stop elements 23 and the second counter-stop surface 25 of another of the counter- stop elements 23 defines a housing seat 26 of at least one of the stop elements 21.

Moreover, the stop elements 21 are made on the first abutment surface 7a of the intermediate body 5 and the counter- stop elements 23 are made on the second abutment surface 7b of the container body 2.

Each counter-stop element 23 has a substantially rectangular triangle profile and each housing seat 26 has a substantially rectangular triangle profile complementary to the profile of each counter- stop element 23.

As can be seen from Figures 4 and 5, the abutment surface 7a of the first body 2 has a saw tooth profile.

Alternative embodiments cannot however be ruled out wherein the counter- stop elements 23 have different profiles, e.g. rectangular, quadrangular or parallelepiped.

Consequently, each stop element 21 has a substantially elongated shape and, in a rest position, has an inclination with respect to the abutment surface 7a of the container body 2 substantially coincident with the inclination of each second counter- stop surface 25.

Furthermore, each first stop surface 22 is oriented so that, in the rest position, it is substantially facing each first counter-stop surface 24.

Usefully, the abutment surface 7b of the intermediate body 5 comprises a plurality of housing cavities 27, each of which is adapted to contain one of the stop elements 21.

With particular reference to the illustrations, the first coupling means 19, the second coupling means 15, the third coupling means 13 and the fourth coupling means 10 are threaded profiles.

Specifically, the first coupling means 19 coincide with a first threaded profile 19 formed on the inner lateral surface of the tail portion 36 of the cover element 18.

The second coupling means 15 coincide with a second threaded profile 15 formed on the outer lateral surface of the first extreme portion 12 of the intermediate body 5.

The third coupling means 13 coincide with a third threaded profile 13 formed on the outer lateral surface of the second extreme portion 11 of the intermediate body 5.

The fourth coupling means 10 coincide with a fourth threaded profile 10 formed on the inner lateral surface of both the third extreme portions 9 of the container body 2.

The tampering detection means 20 are switchable between:

a screwing configuration, in which the intermediate body 5 is rotated with respect to the container body 2 in a screwing direction A in which the stop elements 21 are movable in jogs with respect to the counter-stop elements 23 and each of the stop elements 21 is adapted to engage a respective housing seat 26; and

an unscrewing configuration, in which the intermediate body 5 is rotated with respect to the container body 2 in an unscrewing direction B opposite with respect to the screwing direction A and each of the stop surfaces 22 enters in contact with a respective first counter- stop surface 24, each of the stop elements 21 being subject to breakage as a result of the rotation in the unscrewing direction B of the intermediate body 5 with respect to the container body 2.

As a result of the unscrewing configuration, it is easy to appreciate that following the coupling phase of the intermediate bodies 5 to the container body 2 a tampering operation has been carried out by third parties, because to obtain the breakage of the stop elements 21 it is necessary to exercise a voluntary rotation of the intermediate bodies 5 in the unscrewing direction B by third parties.

It has in practice been ascertained that the described invention achieves the intended objects.

In particular, the fact is underlined that the device to which this treatise relates allows the interconnected electrical cables to easily extricate themselves from tangles of other cables and/or obstacles of various types during their movement, thus reducing the risk of the cables themselves becoming jammed and/or damaged.

Furthermore, the fact is underlined that the device made this way permits ensuring a high degree of water-tightness and protection of the electrical connections from malfunctions due, for example, to the infiltration of water and/or dust inside the device itself once this has been mounted.

In addition, the device made this way permits the immediate detection of any tampering with the devices due to human actions carried out by third parties after the first wiring of the electrical cables and the assembly of the device by the operator in order to prevent any anomalies in the electrical connections between the electrical cables.