FR2768863A1 - CONNECTION DEVICE WITH SELF-INSULATING CONTACT ELEMENT - Google Patents

Abstract

The invention relates to a connection device with a self-stripping contact element for connecting the conductors of cables or electric wires, in particular to a metal strip of a terminal block of an electrical device or the like. The self-stripping contact element mainly comprises a substantially tubular cylindrical part (13) which is in permanent contact with a metal bar (14) and which comprises at one end an end piece (13b) adapted to receive an external tool such as a screwdriver for example, and a side wall 13a provided with a slot (16) with sharp edges to ensure the self-stripping connection. The device is simple, economical and particularly reliable.

Description

CONNECTION DEVICE WITH SELF-CONTACT ELEMENT

STUNNING

  The present invention relates to a connection device with a self-stripping contact element, for the connection of conductors of cables or of electric wires or of metal bars or the like, to a metal distribution bar of a terminal of a distribution panel. , of a

electric or similar device.

  A system of this type is already known, described in particular in European patent application EP 0 697 749 A1. In this embodiment the self-stripping contact element has two sharp edges to allow the insulation to be cut and to ensure contact with the conductor of a cable or an electric wire. This self-stripping contact element is fixed and is associated with means for pushing the cable or the electric wire between the parallel edges.

of the contact element.

  This realization is complex, expensive and does not guarantee in a certain way the realization of a reliable connection. In fact, the means for pushing the cable comprise a screw placed inside a pusher which

  moves in translation in a well under the effect of the rotation of the screw.

  To move the pusher sufficiently to bring the cable into the self-stripping contact element, that is to say to ensure its connection, it

  the screw must be given several full turns.

  In addition, the cable is not held during this operation and can escape if it is not retained in position by the operator before being locked in position by the action of the sharp edges of the element. of self-stripping contact on

  The insulation of the cable or electric wire.

  The present invention proposes to offer a connection device with a self-stripping contact element as defined in the preamble and which does not have the cited drawbacks of the known system. It has very few parts, which makes it economical and reliable. The cable or electric wire remains in a fixed position during the connection operation, which guarantees the quality of the connection. The movement to which the contact element is subjected is a simple displacement, in this case preferably a rotation of a quarter or a half-turn, which allows the mechanical parts of the system to be simplified to the extreme and therefore reduce the costs of

production.

  For this purpose, the device is characterized in that the self-contacting element

  stripping includes a part of substantially cylindrical, tubular shape, mounted in a housing such that the part is rotatable about its axis of symmetry inside this housing, this part being in contact with said metal bar and comprising a part of the means provided at one of its ends for rotating it using a tool, such as in particular a key or a screwdriver, and on the other hand at least one opening in the form of an elongated slot formed on its side wall, this slot having at least one cutting edge and a transverse dimension progressively reducing from one longitudinal end of the slot to the other, by a value corresponding at least to the section of the cable or of the electric wire to connect to a value corresponding at most to the conductor cross section

of this electric cable or wire.

  Preferably, the self-stripping slot extends over a length corresponding to an angle between 45 and 270 and preferably

close to 180.

  The part of substantially tubular cylindrical shape of the self-stripping contact element advantageously comprises several slots arranged in parallel. These slots can have different cross sections to match cable or wire diameters

different electrics.

  The present invention will be better understood with reference to the description

  of embodiments given by way of nonlimiting examples and in the accompanying drawings in which: - Figure 1A shows a sectional view of an embodiment of the connection device according to the invention in a position in which the cable is not yet connected, - Figure 1B shows a view similar to that of Figure 1A, in which the connection device is in a position where the cable is connected, - Figures 2A and 2B are perspective views showing two particular embodiments of a self-stripping contact element of the device according to the invention, - Figure 3 illustrates a very simple connection distribution terminal block comprising connection devices according to the invention, - Figure 4 is a perspective view of the distribution terminal block of Figure 3, partially cut to show the arrangement of the connection devices it contains, Figure 5 is a perspective view of a va laughing embodiment of the self-stripping contact element, FIGS. 6A, 6B and 6C are views respectively in perspective and in

  elevation of another alternative embodiment of the self-contact element

  stripping, which allows by its form a coupling with a tool such as a key or a screwdriver to drive it in rotation about its axis of symmetry, - Figures 7A, 7B, 7C and 7D are perspective views illustrating a another embodiment of the device according to the invention and a particular use of this device, and - Figures 8, 8a, 8b, 8c illustrate another embodiment of the device of the invention. With reference to FIGS. 1A and 1B, the connection device 10 is for example mounted in a distribution box 11 which comprises at least one housing 12 for receiving this device. This device could also be mounted in any other electrical appliance to serve as a terminal for

  connection of external conductors of a circuit.

  The connection device 10 proper comprises mainly a self-stripping contact element consisting of a substantially cylindrical tubular part 13 composed of a side wall 13a and an end piece 13b which extends the side wall towards the end open of the housing 12. The end piece 13b preferably has a reduced section relative to the diameter of the side wall 13a and comprises a central recess 13c, described in more detail with reference to FIGS. 2A and 2B, which allows, by its shape, a coupling with a tool such as a wrench or a screwdriver to drive the part 13 in rotation about its axis of symmetry. The central recess could also be replaced by a protuberance with two opposite flat faces to allow the use of a key, such as a

fork for example.

  The distribution terminal block 11 comprises a metal strip 14 for electrical connection which can have any shape provided that it is adapted to be in close contact with the part 13. For this purpose, this part 13 comprises at least one zone 15 having a smooth peripheral surface which ensures reliable electrical contact with said strip

metallic 14.

  The side wall 13a of the part 13 has an elongated slot-shaped opening 16, the cross section of which passes by a value equal to or greater than the diameter of the cable or electric wire 17 comprising a central conductor 18 and at least one peripheral layer d an insulator 19, in the vicinity of one of its ends, to an equal value and, preferably, slightly less than the diameter of the central conductor 18, in the vicinity of its opposite end. The edges 16a and 16b of the slot 16 are sharp so that the insulation 19 is cut and the conductor 18 is slightly cut when the cable or the electric wire is passed from one end of this slot to the other. This passage takes place without displacement of the cable or of the electric wire 17, but following a rotation of the part 13. The two positions are respectively represented by FIGS. 1A and 1 B. It will be noted that means (not shown) forming a stop limiting the rotational stroke of the cylinder may be provided for example in the part

  lower or upper of said cylinder.

  FIGS. 2A and 2B represent, in the form of perspective views, two alternative embodiments of the piece 13 of substantially cylindrical tubular shape. The tip 13b has in its central part a recess 20 which corresponds to the profile of a Phillips screwdriver in the construction according to the

  Figure 2A and a flat screwdriver in the construction according to Figure 2B.

  We see in these figures the particular shape of the slot 16 and its edges

cutting edges 16a and 16b.

  FIG. 3 represents the distribution terminal block 11, seen in perspective, and represented in section by FIGS. 1A and 1 B. It comprises an elongated body having several housings 12 in which are arranged several connection devices 10. To each housing 12 containing a connection device 10 corresponds an opening in the form of an access tunnel 21, disposed laterally on the body of the terminal block 11, for receiving and guiding a cable or an electric wire 17 in the direction of the slot 16

  stripping of the corresponding self-stripping contact element.

  Figure 4 shows the distribution terminal 11 of Figure 3, partially cut and shows in particular, the specific shape of the metal distribution bar 14 which ensures electrical contact with the parts

  substantially cylindrical tubular 13 of the self-contacting elements

  naked. This bar is folded so as to form a succession of inverted U 22 in which the parts 13 are embedded. The close contact of the metal bar and the corresponding part 13 is ensured in three bearing zones whatever the position of the piece, which guarantees a

good electrical connection.

  Figure 5 shows an alternative embodiment of the part 13 whose side wall 13a is provided with three slots 16 arranged in parallel, respectively intended to ensure the connection of three cables or electrical wires 17. These slots may be identical or have different dimensions to allow connection of electrical cables or wires from

different diameters.

  According to another embodiment, a slot that can accept cables or wires of

  different diameters, as shown in Figure 9, can be used.

  This slot comprises, between the cable insertion zone and the connection zone, a set of slots (c) located on either side of the axis (x)

from the slot.

  FIGS. 6A, 6B and 6C respectively represent perspective (FIG. 6A) and elevation views (FIGS. 6B and 6C) of another alternative embodiment of a substantially cylindrical and tubular part 13 of the self-contacting element. naked. In this embodiment, the side wall 13a of the part 13 comprises three slots arranged substantially parallel, ie a central slot 16 substantially identical to that described above, intended to receive a conductive bar 23, and two slots 24, with non-cutting parallel edges which have the sole function of

  give elastic properties to part 13.

  It will be noted that in this embodiment, the mechanical stops corresponding to the "connected" and "disconnected" positions of the device are advantageously formed by the two edges of the slot located at its two ends. The operating principle is identical to that described above. The metal bar is engaged like the cable or the elastic wire in the slot, 16 and the part 13 is turned so that the edges of the slot bite.

  their cutting edges in the thickness of the conductor.

  FIGS. 7A, 7B, 7C illustrate another embodiment of the substantially cylindrical tubular part of the insulation displacement contact element, as well as a specific use of the device 10. The part 13 is composed of two parts, a metal part 30 and an insulating part 31 in the form of a stud, retained by two tabs 32 cut in the side wall 13a of the part 13, and which engage in two recesses 33 diametrically

  opposite formed in the stud constituting the insulating part 31.

  This part 13 is associated with a metal plate 34 in which are formed cells 35 intended to receive the lower part of the part 13. When this part 13 is engaged in the corresponding cell of the metal plate 34, it can occupy two positions illustrated respectively by FIGS. 7C and 7D. In the position of FIG. 7C, the contact between the part 13 and the metal plate 34 is made at the level of the insulating part 31, the metal tabs 32 being arranged in the elongated zone of the cell and having no contact with the walls of the latter and, consequently, with the metal plate 34. In the position of FIG. 7D, the contact between the part 13 and the metal plate is made by means of the metal lugs 32. In this position, the

  contact between the part 13 and the metal plate is established.

  Consequently, this device makes it possible to electrically disconnect the part 13 from the metal plate 34 at the time of the introduction of an electric cable or wire with a view to its connection and to ensure the electrical coupling at the time of rotation. of part 13 at the same time as the

  connection of cable or electric wire, metal bar or the like.

  Figures 8, 8a, 8b, 8c show a particular embodiment of the part 13 by winding and crimping. The pre-cut piece (fig. 8) is rolled up (fig. 8a, 8b, 8c), then the lips (I) located at the ends are

set at around 45.

  The slot 30 constitutes the connection element with the strip 14, which may as well be the connection area of an appliance of the type

  circuit breaker or contactor, or the connection strip in Figure 4.

Claims (12)

  1. Connection device with self-stripping contact element, for the connection of conductors of cables or electric wires or metallic bars or the like, to a metallic distribution bar of a terminal of a distribution terminal block, an electrical or similar device, characterized in that the self-stripping contact element comprises a part (13) of substantially cylindrical, tubular shape, mounted in a housing (12) in such a way that the part is rotatable about its axis of symmetry inside this housing, this part being in contact with said metal bar (14) and comprising on the one hand means provided at one of its ends for rotating it by means of a tool, such as in particular a wrench or a screwdriver, and on the other hand at least one elongated slot-shaped opening (16) formed on its side wall (13a), this slot having at least one cutting edge and a transverse dimension r gradually reducing from one longitudinal end of the slot to the other, by a value corresponding at least to the section of the cable or electric wire (17) or the like to be connected to a value corresponding at most to the section of the   conductor of this cable or electric wire.   2. Device according to claim 1, characterized in that said means provided at one of the ends of the part (13) of substantially cylindrical tubular shape of the self-stripping contact element comprise an end piece (13b) having a protrusion or a recess (13c) having at least two substantially parallel planar surfaces, to provide a   taken with a wrench or screwdriver.   3. Device according to claim 2, characterized in that said end piece (13b) has a narrowed section relative to the section of the side wall (13d) of the part (13).   4. Device according to claim 1, characterized in that the side wall of the part of substantially cylindrical tubular shape of the self-stripping contact element comprises at least one zone having a smooth peripheral surface (15) which is in close contact with said metal strip (14).   5. Device according to claim 1, characterized in that said slot (16) extends over a length corresponding to an angle between 45 and 270, and preferably close to 180 6. Device according to claim 1, characterized in that said part (13) of substantially cylindrical tubular shape of the contact element comprises   several slots (16) arranged substantially parallel.   7. Device according to claim 6, characterized in that the different slots (16) have different transverse dimensions and are arranged to ensure the connection of cables and / or electrical wires (17) and / or bars   of different sections.   8. Device according to claim 1, characterized in that said part (13)   of substantially cylindrical tubular shape of the self-contacting element   stripping includes at least one additional slot (24) formed in   its side wall (13a), to give elasticity to the latter.   9. Device according to claim 8, characterized in that said slot (24)   additional has parallel, non-cutting edges.   10. Device according to claim 1, characterized in that said piece of   substantially cylindrical tubular shape of the self-contacting element   stripping includes a metal part and an insulating part (31) in the form of a stud held in position by means of two metal tabs (32) engaged in recesses (33) of said stud, this piece being i! arranged to be arranged in cells (35) of a metal plate (34), such that the electrical contact between the part (13) and the metal plate (34) is established or interrupted depending on the position of the part ( 13), the physical contact between the part and the plate taking place either at the level of the metal tabs (32) or at the level of the insulating part (31) in   stud shape, depending on the position of the part (13).   11. Device according to any one of claims 1 to 6, characterized in   that at least one of the slots comprises, between the cable insertion zone and the connection zone, a set of slots (C) situated on the opposite side and on the other side of the axis (X) of the slot.   12. Device according to any one of the preceding claims,   characterized in that the connection cylinder is produced by winding and   crimping of a precut part.