Electric connector

Abstract: An electric connector (2) having an insulating casing (4) defining a number of cavities (5) for housing respective electric terminals (6) and having axes parallel to a first direction (A) wherein the connector (2) is connected to a complementary connector (3); a retaining element (35) for retaining the terminals (6) inside the cavities (5) and connectable in sliding manner to the casing (4) and into a closed position in a second direction (B) crosswise to the first direction (A); and a tab (51) which projects from the casing (4), is normally set to a disabling position disabling connection of the connector (2) and the complementary connector (3) and interfering with a connecting region (14) of the connectors (2, 3), and which can be set, by interacting with the retaining element (35) and when the retaining element (35) is in the closed position, to an enabling position enabling connection of the connector (2) and the complementary connector (3) and wherein the tab (51) does not interfere with the connecting region (14).

Description: The present invention relates to an electric connector, in particular, but not exclusively, to an electric plug connector connectable to a complementary electric socket connector to form an electric connecting unit having a large number of ways, of the type used to connect an electric system to an electronic central control unit. Connecting units of the above type are known in which, as described for example in US Patent 5,725,398, the connectors comprise respective insulating casings defining respective numbers of cavities for respectively housing mutually connectable male and female electric terminals. One of the connectors also comprises a terminal retaining grille which is fitted to the front of the respective casing in the opposite direction to that in which the terminals are inserted inside the respective cavities. In addition to retaining the terminals inside the cavities of the respective casing, the retaining grille also prevents the respective connector from mating with the complementary connector if the terminals are not inserted correctly inside the respective cavities. For which purpose, the retaining grille comprises a pair of projections defining respective stops for the complementary connector to prevent engagement of the connectors when the grille is not fitted completely to the respective casing. More specifically, the projections are hinged to the body of the grille by means of thin strips of material, which bend to move the projections clear of the mating path of the casings when the grille is fitted completely to the respective casing. A major drawback of connectors of the above type lies in their still being connectable even if, by mistake, the retaining grille is not fitted to the respective casing; in which case, no provision is made for checking correct engagement of, or retaining, the terminals inside the respective cavities. The retaining function is particularly important in the case of connecting units having a large number of ways, and which call for a certain amount of force to mate the connectors. In the absence of the retaining grille, and on account of the force required to mate the connectors, the terminals, in fact, may undergo displacement and/or deformation which could impair correct performance of the connecting unit as a whole. Improper assembly of one or more of the terminals may also go unnoticed during testing, on account, for example, of the terminals being so positioned as to anyway establish a precarious electrical contact, which, in applications in which the connector is subject to vibration, as on motor vehicles, is bound to fail eventually, with all the consequences this entails. It is an object of the present invention to provide an electric connector designed to eliminate, in a straightforward, low-cost manner, the aforementioned drawback typically associated with known connectors. According to the present invention, there is provided an electric connector comprising an insulating casing defining a number of cavities for housing respective electric terminals and having axes parallel to a first direction wherein said connector is connected to a complementary connector; and at least one retaining element connectable in sliding manner to said casing in a second direction crosswise to said first direction and into a closed position retaining said terminals inside said cavities; whereby said casing comprises at least one disabling element, which is normally set to a disabling position disabling connection of said connector and said complementary connector and interfering with a connecting region of said connector and said complementary connector, and which is set, by interaction with said retaining element, to an enabling position enabling connection of said connector and said complementary connector, and wherein said disabling element does not interfere with said connecting region. A preferred, non-limiting embodiment of the present invention will be described by way of example with reference to the accompanying drawings, in which: Figure 1 shows a view in perspective of the component parts of an electric connecting unit comprising an electric plug connector in accordance with the present invention, and a complementary electric socket connector; Figure 2 shows a larger-scale longitudinal section of the electric plug connector in Figure 1; Figure 3 shows a larger-scale cross section, with parts removed for clarity, of the electric plug connector in Figure 1; Figure 4 shows a larger-scale view in perspective of a detail of the Figure 1 plug connector in a first operating position; Figure 5 shows a larger-scale view in perspective of the Figure 4 detail in a second operating position; Figures 6 and 7 show sections of the Figure 4 and 5 details of the plug connector in the respective operating positions and in course of assembly inside a seat on the Figure 1 socket connector. Number 1 in Figure 1 indicates as a whole an electric connecting unit with a large number of ways, and in particular for connecting an electronic central control unit (not shown) to a vehicle electric system. Unit 1 comprises a first plug connector 2 and a second socket connector 3 connectable to each other in a direction A. Connector 2, according to the present invention, comprises an insulating casing 4 made of plastic material and defining a number of cavities 5 (Figures 2 and 3), which have respective axes parallel to direction A, and are aligned in a number of transverse rows - four in the example shown - extending parallel to a direction B perpendicular to direction A. Cavities 5 house respective female electric terminals 6 connected to respective electric cables 7 and retained inside cavities 5 by primary and secondary retaining means described later on. Casing 4 comprises a hollow, substantially parallelepipedal main body 8 having an outer lateral tubular appendix 9 for guiding cables 7; and a substantially parallelepipedal supporting block 10 for supporting terminals 6, and which extends inside main body 8 and defines the rows of cavities 5 (Figure 2). Connector 3 - which is only described herein as required for a clear understanding of the present invention - comprises a substantially parallelepipedal insulating casing 11 conveniently formed integrally with the outer casing (not shown) of the electronic central control unit, and housing a number of male electric terminals 12 extending parallel to direction A and connected to respective electric cables (not shown). Casing 11 defines a front seat 15 for receiving block 10 of connector 2, and in which project respective contact portions 16 of terminals 12. Unit 1 also comprises a lever device 17 permitting connection of connectors 2 and 3 with very little manual force, and which is only described briefly below, by not forming part of the present invention. Device 17 comprises a slide 18 movable inside and with respect to casing 4 in direction B. Slide 18 is substantially C-shaped, and comprises two spaced, substantially flat lateral walls 19 parallel to directions A and B, and a transverse end wall 20. Lateral walls 19 of slide 18 slide inside respective lateral walls 21 of main body 8 of casing 4 and outside block 10; and main body 8, block 10 and lateral walls 19 of slide 18 define a seat 14 for receiving casing 11 of connector 3 in use, and so defining a connecting region of connectors 2 and 3. Each lateral wall 19 comprises a number of cam slots 22 which cooperate with respective pins 23 on the outside of casing 11 to move connectors 2 and 3 towards each other when slide 18 is moved inwards of casing 4 in direction B. The shape of slots 22 is known from EP 0 363 804-A and therefore not described. Device 17 also comprises an activating lever 24 hinged to casing 4 and to lateral walls 19 of slide 18 so that rotation of lever 24 corresponds to translation of slide 18 in direction B and, by virtue of pins 23 engaging slots 22, to mutual engagement of connectors 2 and 3 and terminals 6 and 12 in direction A. More specifically, lever 24 is movable with respect to casing 4 between a raised or open position (Figure 1) corresponding to maximum projection of slide 18 from casing 4, and a lowered or closed position on casing 4, which corresponds to full insertion of lateral walls 19 of slide 18 inside casing 4, and to a fully engaged position of connectors 2 and 3 and terminals 6 and 12. With particular reference to Figures 2 and 3, each terminal 6 of connector 2 comprises a substantially cylindrical tubular front contact portion 25 which is engaged by the contact portion 16 of a corresponding male terminal 12 of connector 3; a rear portion 26 for connection to respective electric cable 7; and an intermediate portion 27 interposed between, and smaller in section than, portions 25 and 26. Each terminal 6 is inserted inside respective cavity 5 through a rear opening 28 of the cavity, from which respective electric cable 7 projects in use, and is positioned with contact portion 25 facing a front opening 29 of cavity 5. The primary retaining means comprise, for each terminal 6, a retaining seat 30 formed in the lateral wall of respective cavity 5; and an elastic lance 31 (Figure 3) projecting outwards from contact portion 25 of terminal 6, substantially in a direction parallel to direction A and towards intermediate portion 27, and which clicks onto seat 30. With reference to Figures 2 to 7, the secondary retaining means comprise a substantially comb-shaped movable retaining element 35 formed separately from casing 4, and which is fitted in sliding manner, in direction B, inside a transverse seat 36 of block 10 of casing 4 perpendicularly intersecting cavities 5. More specifically, block 10 comprises a parallelepipedal rear portion 37 integral with main body 8 and having a number of first through holes; and a parallelepipedal front portion 38 which clicks inside main body 8 into a position adjacent to portion 37, and has a second number of through holes aligned with and defining cavities 5 with the first through holes. Seat 36 is defined on opposite sides by portions 37 and 38 of block 10. Seat 36 communicates with seat 14 through two shaped openings 39, 40 having respective profiles complementary to that of the cross section of retaining element 35, and formed in respective opposite walls 41, 42 of block 10 parallel to end wall 20 of slide 18 (Figure 2). Retaining element 35 comprises a base portion 43 substantially in the form of a bar; and a number of arms 44 - five in the example shown - extending perpendicularly to base portion 43, and cooperating in pairs, and on opposite sides of each row of cavities 5, with the intermediate portions 27 of respective terminals 6 correctly engaged inside respective cavities 5. More specifically, arms 44 of retaining element 35 define a number of gaps equal to the number of rows of cavities 5 - four in the example shown - and which are slightly larger in section than intermediate portions 27 of terminals 6, but smaller than the other sections of terminals 6, so that, only when terminals 6 are all inserted properly inside respective cavities 5, i.e. with respective intermediate portions 27 inside seat 36, can retaining element 35 be set to a closed position fully inserted inside seat 36, and with arms 44 cooperating laterally with terminals 6 to retain them inside cavities 5. Arms 44 of retaining element 35 each have a parallelepipedal section, terminate with respective tapered, substantially truncated-pyramid-shaped free ends 45, and have, on opposite sides, respective longitudinal, parallelepipedal guide projections 46 which engage in sliding manner respective complementary slots 47 formed in the lateral walls of the rows of cavities 5. Retaining element 35 is inserted inside seat 36 through three successive openings, namely : a rectangular through opening 48 formed in end wall 20 of slide 18; a shaped opening 49 having a profile complementary to that of the section of retaining element 35, and formed in a wall 50 of main body 8 parallel to walls 41, 42; and opening 39 in wall 41 of block 10. When retaining element 35 is in the closed position, ends 45 of arms 44 engage opening 40 in wall 42 of block 10. According to the present invention, portion 38 of block 10 comprises a tab 51 (Figures 4 to 7) which projects from wall 42, is normally set to a disabling position disabling connection of connectors 2 and 3 (Figures 4 and 6) and wherein tab 51 is inclined slightly with respect to direction A with a respective end portion 52 projecting from block 10 inside seat 14 so as to interfere with casing 11 of connector 3 in direction A, and, by interacting with retaining element 35, can be set, when retaining element 35 is in the closed position, to an enabling position enabling connection of connectors 2 and 3 (Figures 5 and 7) and wherein tab 51 is housed entirely within the outer profile of block 10. Tab 51 is engaged inside a slot 53 in wall 42 of block 10, and is secured integrally, by a respective intermediate portion 54, to block 10 by an elastic hinge 55 defined by a strip of plastic material. When retaining element 35 is in the closed position, ends 45 of arms 44 exert thrust on an opposite end portion 56 of tab 51 to end portion 52. Tab 51 also decreases in section from end portion 52 to end portion 56. Unit 1 is assembled by moving connectors 2 and 3 towards each other in direction A so that pins 23 engage the initial portions of respective slots 22, and by then rotating lever 24 from the raised Figure 1 position to the lowered position, after first fitting terminals 6, 12 inside respective casings 4, 11 and setting retaining element 35 to the closed position in block 10 of casing 4. In the event any one of terminals 6 is not inserted properly inside respective cavity 5, seat 36 is engaged by contact portion 25 as opposed to intermediate portion 27 of terminal 6, thus preventing full insertion of retaining element 35 inside seat 36. That is, arms 44 are arrested by interacting with contact portion 25 of terminal 6, which, as stated, is larger in section than the gaps of retaining element 35. Given the impossibility of fully inserting retaining element 35 inside seat 36, ends 45 of arms 44 are therefore prevented from interacting with end portion 56 of tab 51, which remains in the disabling position interfering with casing 11 to prevent connection of connectors 2 and 3 (Figures 4 and 6). Similarly, assembly of unit 1 is also prevented if, by mistake, retaining element 35 is not inserted inside seat 36, in which case, tab 51 again remains in the disabling position. Conversely, if terminals 6 are all inserted properly inside respective cavities 5, i.e. with lances 31 of terminals 6 clicked onto retaining seats 30 of cavities 5, retaining element 35 is able to slide inside seat 36 in direction B into the closed position, by the gaps of retaining element 35 being engaged by intermediate portions 27 of terminals 6. In which case, ends 45 of arms 44 exert thrust, in direction B, on end portion 56 of tab 51, so as to rotate tab 51 about elastic hinge 55 into the enabling position wherein tab 51 is housed completely within the outer profile of block 10 and, in particular, of wall 42 (Figures 5 and 7). Block 10 of casing 4 may therefore slide inside seat 15 of casing 11 to complete connection of connectors 2 and 3. The advantages of connector 2 according to the present invention will be clear from the foregoing description. In particular, tab 51 prevents connection of connectors 2 and 3 both in the event any one of terminals 6 is not inserted properly inside respective cavity 5, thus preventing retaining element 35 from being set to the closed position, and in the event retaining element 35 is not fitted, by mistake, inside seat 36. Clearly, changes may be made to connector 2 as described herein without, however, departing from the scope of the present invention.

Claims: An electric connector (2) comprising an insulating casing (4) defining a number of cavities (5) for housing respective electric terminals (6) and having axes parallel to a first direction (A) wherein said connector (2) is connected to a complementary connector (3); and at least one retaining element (35) connectable in sliding manner to said casing (4) in a second direction (B) crosswise to said first direction (A) and into a closed position retaining said terminals (6) inside said cavities (5); whereby said casing (4) comprises at least one disabling element (51), which is normally set to a disabling position disabling connection of said connector (2) and said complementary connector (3) and interfering with a connecting region (14) of said connector (2) and said complementary connector (3), and which is set, by interaction with said retaining element (35), to an enabling position enabling connection of said connector (2) and said complementary connector (3), and wherein said disabling element (51) does not interfere with said connecting region (14). A connector as claimed in Claim 1, characterized in that said retaining element (35) is a bar, and is fittable in sliding manner inside a transverse seat (36) of said casing (4) intersecting said cavities (5). A connector as claimed in Claim 1 or 2, characterized in that said retaining element (35) is substantially comb-shaped, and has a number of arms (44) which cooperate laterally with said terminals (6). A connector as claimed in Claim 2 or 3, characterized in that said seat (36) communicates with said connecting region (14) through a first opening (39) permitting insertion of said retaining element (35) inside the seat (36), and through a second opening (40) opposite said first opening (39); and in that said disabling element (51) is a tab projecting from said casing (4) at said second opening (40). A connector as claimed in Claim 4, characterized in that said disabling element (51) comprises an intermediate portion (54) connected to said casing (4) by an elastic hinge (55); a first end portion (56) which cooperates with respective free ends (45) of said arms (44) of said retaining element (35); and an opposite second end portion (52) which projects from said casing (4) in said disabling position; said retaining element (35), in said closed position, engaging said second opening (40) and pushing said first end portion (56) of said disabling element (51) so as to rotate the disabling element (51), about said elastic hinge (55), from said disabling position to said enabling position. A connector as claimed in any one of the foregoing Claims, characterized in that said casing (4) comprises a hollow main body (8), and a supporting block (10), which supports said terminals (6), extends inside said main body (8), supports said disabling element (51) in projecting manner, and, in use, engages a seat (15) of said complementary connector (3); said disabling element (51) projecting outside said supporting block (10) and inside said main body (8) in said disabling position, and being confined within the outer contour of the supporting block (10) in said enabling position. A connector as claimed in Claim 6, characterized in that said disabling element (51) engages a slot (53) formed in an outer lateral wall (42) of said supporting block (10). A connector as claimed in any one of Claims 3 to 7, characterized in that said arms (44) comprise, on opposite sides, respective longitudinal guide projections (46) which engage in sliding manner respective correspondingly shaped grooves (47) formed in respective lateral walls of said cavities (5).

Inventors: BIGOTTO PIER CARLO, RAMPONE RENZO, BIGOTTO, PIER CARLO, RAMPONE, RENZO
Applicants: FRAMATOME CONNECTORS INT, FCI
Application year: 1999
Main classification: H01R13
IPC codes: H01R13