FR2725079A1 - Fixing device for linking pin of electrical connector to cylindrical casing - Google Patents

Abstract

The fixing device includes an axial holder for a cable formed of electrical wire conductors and an isolating material insert in a body of a pin. It carries a shaft and male pins which are electrically linked to the conducting wires. A connection casing to which the pin is linked is formed of a plastic material. A body of the fixing device has one part forming a fixing socket for binding a force in the casing. The part which forms the socket includes a number of parallel circular projecting stop which penetrates into the material of the casing.

Description

 The present invention relates to a device for fixing an electrical connector plug to an external cylindrical connection sleeve.

 Such a device is known according to which the connection of the plug body to the external cylindrical sleeve is effected by screwing with the aid of external and internal threads respectively of the plug body and of the external sleeve so as to ensure by means of parts internal axial maintenance of a cable with electrically conductive wires and an insert of insulating material housed in the plug body and carrying drums and male pins electrically connected to the conductive wires.

 However, this known device due to the presence of internal and external threads is relatively expensive to produce. In addition, during the screwing operation of the external sleeve on the plug body, the internal parts are subjected to relative rotations which risk in particular causing connection breakage by welding of some of the conductive wires to the female sockets or male pins. of the insulating material insert. Furthermore, the automatic assembly operations of the various parts housed in the external connection sleeve are extremely complicated, which consequently increases the manufacturing costs.

Finally, the tightness of the device is poorly ensured and must be seriously checked.

 The present invention aims to eliminate the above drawbacks of the known device.

 To this end, the invention provides a device for fixing an electrical connector plug to an external cylindrical connection sleeve allowing the axial maintenance of a cable with electrically conductive wires and an insert of insulating material housed in the body. of plug and carrying drums and male pins electrically connected to the conductive wires and which is characterized in that the connection sleeve is made of a plastic material and the plug body comprises a part forming a fixing sleeve by force fitting in the sleeve connection.

 Preferably, the part forming the fixing sleeve comprises a certain number of parallel circular projecting edges penetrating into the material of the connection sleeve so as to make the connection between plug body and connection sleeve impossible to dismantle.

 Advantageously, the projecting edges have a sawtooth configuration.

 According to one embodiment, the device comprises a number of coaxial parts internal to the connection sleeve maintained axially in forced abutment on each other between the plug body and the connection sleeve and comprising a plastic stop ring bearing against the insert of insulating material traversed by the aforementioned conductive wires; a metal spacer partly arranged on the stop ring coming to bear on a flange of the stop ring and having at its end opposite to the stop ring a part of frustoconical shape; a ring forming a clamp mounted on the frustoconical part of the spacer so as to clamp between them a braided part of the cable shielding and comprising flexible tongues toothed internally to fix axially by pinching the cable extending as far as the spacer; an internally bi-conical ring comprising two opposite frustoconical bores, one bearing on the flexible tabs to flex them radially internally; and an elongated sleeve of elastomeric material mounted with little play on the cable and having an internal part forming a frustoconical head housed in abutment in the other frustoconical bore of conjugate shape of the biconic ring and a circular shoulder for connection to a substantially cylindrical part of the elongated sleeve exiting from the external connection sleeve which has a radial closure wall in abutment on the circular shoulder of the head of the elongated sleeve.

 The aforementioned clamp ring and the internally bi-conical ring are made of plastic and / or metal.

The invention will be better understood and other objects, characteristics, details and advantages thereof will appear more clearly in the explanatory description which follows, made with reference to the appended schematic drawings given solely by way of example illustrating an embodiment. of the invention and in which
- Figure 1 is a top half-view in section in a median longitudinal plane of the device of the invention fixing an electrical connector plug to an external cylindrical connection sleeve; and
- Figure 2 is an exploded view showing the various assembly parts used with the fixing device of the invention.

 Referring to the figures, the reference 1 designates a plug intended to be electrically connected to another part (not shown), such as a base, to form an electrical connector.

 The plug 1 comprises a plug body 2 housed in an outer ring 3 movable axially relative to the plug body 2 so as to allow the unlocking of the other part of the connector locked to the plug body 2. For this purpose, a latch 4 is pivotally mounted between the plug body 2 and the unlocking ring 3 projecting in part through an orifice 5 formed in the wall of the plug body 2. An annular spring 6 surrounds the end part of the latch 4 so to resiliently recall the protruding part of the latch 4 through the orifice 5. The latch 4 has its end part opposite to that protruding through the receiving orifice 5 bearing on an inclined inner wall portion 3a of the unlocking ring 3 and cooperating with the latch 4 so as to disengage it from the orifice 5 when the unlocking ring 3 is moved axially to the right with respect to FIG. 1 and thus unlock the other pa connector body connector 2. Of course, the other connector part has at its free end a flange on which the protruding part of the latch 4 is supported to prevent the axial withdrawal of this connector part from the plug body 2 as long as the lock 4 is in the active locking position.

 The plug body 2 comprises a collar 7 held in abutment on a rod 8 housed in the unlocking ring 3 by means of a return spring 9 mounted prestressed between the collar 7 and a washer 10 mounted coaxially on the end corresponding cylindrical of the plug body 2 and in abutment against an internal circular shoulder 11 of the unlocking ring 3 so as to move the latter axially relative to the plug body 2 by compressing the return spring 9.

 An insert of insulating material 12 housed in the plug body 2 carries drums 13 and male pins 14, the drums or pins being connected to conductive wires 15, only one of which is shown, of a cable of conductive wires 16 .

As shown in FIG. 1, the drums 13 are electrically connected, for example by welds 17 or by crimps, to the conductive wires 15, but it is understood that the drums 13 can be replaced by the male pins 14 depending on whether the part to be electrically connected to the plug body 2 has male pins or female sockets.

 The plug body 2 is fixed to an external cylindrical sleeve 18 allowing, by means of internal parts, which will be described later, the axial retention of the cable 16 and of the insert of insulating material 12.

 According to the invention, the connection sleeve 18 is made of a plastic material, such as for example polyamide, and the plug body 2 comprises a socket part 19 on which are machined several parallel circular projecting edges 20 of sawtooth penetrating into the plastic material of the connection sleeve 18 when it is assembled to the plug body 2 so as to make the connection between the plug body 2 and the sleeve 18 impossible to dismantle.

 The various internal parts present in the external sleeve 18 and held axially in forced support one on the other between the plug body 2 and the sleeve 18 will now be defined.

 These parts comprise a plastic stop ring 21 having a cylindrical end 21a engaging in a bore of conjugate shape of the insert 12 and bearing on the circular end edge of the insert 12 via a collar 21b. The insert 12 is immobilized in rotation in the plug body 2 by a lug 12a housed in a groove 2a of the body 2. An O-ring 22 is interposed between the plug body 2 and the insert 12 to ensure sealing. The internal parts also include a metal spacer 23 partially mounted on the stop ring 21 by coming to bear on the flange 21b thereof and ending at its end opposite to the stop ring 21 by a shaped part frustoconical 23a.

The spacer 23 also includes a shoulder 23b which comes to bear on the circular end of the socket 19 of the plug body 2. The cable 16 partially crosses the spacer 23 and the conductive wires pass through the remaining part of the spacer 23 and the ring 21 to be welded or crimped to the barrels 13 which protrude into the ring 21. The internal parts also include a ring 24, in this case made of plastic, having the double function of ensuring the continuity of the shielding of the metal braid shielding contained in the cable 16 and to fix it axially. To this end, the ring 24 has a frustoconical bore 24a of shape substantially combined with that of the frustoconical part 23a of the spacer 23 and mounted on the part 23a so as to clamp between them a shielding braid 16a of the cable 16.L 'shoulder 23b which provides electrical continuity between the body 2 and the shielding braid 16a, also ensures the shielding continuity between the housing and the braid. The ring 24 further comprises flexible tongues 24b internally toothed to axially fix the cable 16 by partially crushing it and radially by pinching. A ring 25, forming part of the internal parts, comprises two opposite frustoconical bores 25a, 25b, the bore 25a being in abutment on the tongues 24b in order to flex them radially towards the cable 16 and to hold them in the position for fixing thereof. The internal parts finally comprise an elongated sleeve 26 made of elastomer material and mounted with slight play on the cable 16. The sleeve 26 comprises a part forming a frustoconical head 26a engaging in the frustoconical bore of conjugate shape 25b of the biconic ring 25 for push it axially to the left in view of FIG. 1. The head part 26a is connected to the elongated cylindrical part 26b leaving the sleeve 18 by means of a circular shoulder 26c against which the radial wall 18a of abuts sleeve closure 18.

 The assembly of the different parts of the device described above is extremely easy since it suffices first to thread on the cable 16 the external sleeve 18 then, successively, the elongated sleeve 26, the biconic ring 25, the ring 24, the spacer 23 and the stop ring 21 then, after having welded or crimped the conductive wires 15 to their respective drums 13, the plug body 2 is force fitted into the sleeve 18 to secure them definitively together.

 The device described above of the invention thus consists of a set of extremely simple parts, the assembly of which is carried out in a simple threading operation in a determined order and by compressing them in the axial direction and maintaining them in the compressed state by fixing the plug body 2 to the sleeve 18. The fixing by the edges 20 of the plug body 2 in the sleeve 18 ensures perfect sealing so that it is necessary to use only one single seal 22, that located between the plug body 2 and the insulating insert 12. The device of the invention can thus be used in an extremely harsh environment. It will also be noted that during the assembly of the different parts of the device, it is not necessary to fix the insulating insert 12 in the plug body 2 in advance unlike the prior device and that once the drums are sufficient or pins welded to the conductive wires 15, insert the insert 12 into the plug body 2 by engaging its lug 12a in the groove 2a. The shielding braid 16a fixed between the ring 24 and the metal spacer 23 allows complete shielding with respect to the mass of the conductors of the cable 16 up to the drums 13 or pins 14 if the latter are connected to the wires 15. Finally, the device of the invention can be assembled automatically.

Claims (5)

 1. Device for fixing a plug (1) of an electrical connector to an external cylindrical connection sleeve (18) allowing the axial retention of a cable (16) with electrically conductive wires (15) and of an insert of material insulator (12) housed in the plug body (2) and carrying drums (13) and male pins (14) electrically connected to the conductor wires (15), characterized in that the connection sleeve (18) is in one plastic material and the plug body (2) comprises a part forming a fixing sleeve (19) by force fitting into the connection sleeve (18).  2. Device according to claim 1, characterized in that the part forming the aforementioned fixing sleeve (19) comprises a certain number of parallel circular projecting edges (20) penetrating into the material of the connection sleeve (18) so as to make non-removable the connection between plug body (2) and connection sleeve (18).  3. Device according to claim 2, characterized in that the projecting edges (20) above have a sawtooth configuration.  4. Device according to one of the preceding claims, characterized in that it comprises a number of coaxial parts internal to the connection sleeve (18) held axially in forced abutment on each other between the plug body (2) and the connection sleeve (18) and comprising a plastic stop ring (21) bearing against the insert of insulating material (12) and traversed by the conductive wires (15); a metal spacer (23) partially arranged on the stop ring (21) bearing on a flange (21b) of the stop ring (21) and having at its end opposite to the stop ring ( 21) a part of frustoconical shape (23a); a ring forming a clamp (24) mounted on the frustoconical part (23a) of the spacer (23) so as to clamp between them a braided shielding part (16a) of the cable (16) and comprising flexible tongues (24b) toothed internally for axially pinching the cable (16) extending into the spacer (23); an internally biconical ring (25) comprising two opposite frustoconical bores (25a, 25b), one (25a) bearing on the flexible tabs (24b) to flex them radially internally; ; and an elongated sleeve (26) of elastomeric material mounted with little play on the cable (16) and having an internal part forming a frustoconical head (26a) housed in abutment in the other frustoconical bore of conjugate shape (25b) of the ring internally bicônique (25) and a circular shoulder (26c) for connection to a substantially cylindrical part (26b) of the elongated sleeve (26) leaving the external connection sleeve (18) which has a radial closure wall (18a) in abutment on the 'circular shoulder (26c) of the head (26a) of the elongated sleeve (26).  5. Device according to claim 4, characterized in that the ring forming a clamp and the ring internally (24) biconical (25) are made of plastic and / or metal.