Connecting device between conductive cables and associated terminals

Abstract: A device for facilitating and protecting the connection between conductor cables (C) and associated connection terminals (T) of electrical apparatus (A), particularly the electromagnet of a motor vehicle starter motor, comprising a box-like body (1) having a base (2) and a cover (3) of electrically insulating material. The base has a seat (5,6) for form coupling engagement on to the connection terminal (T) and an aperture (8) for the introduction of conductor cables (C), and the cover (3) is articulated to the base (2) so as to be turnable relative to this between an open position and a closure position. An external retaining member (11) connected to the body (1) is attachable to the said cables (C).

Description: The present invention relates in general to the connection between conductive cables and associated terminals for connection to electrical apparatus. Connections of said type are described in US-A-3 633 154 and in US-A-4 288 504. More particularly, the invention relates to the connection between the connection terminal of the electromagnet of an electric starter motor for an internal combustion engine of a motor vehicle and the associated supply cables co ing from the battery. On the majority of motor cars currently in production, the position of these cables is left to the discretion of the assembly workers. In some cases the positioning is obtained by the use of metal brackets preliminarily fixed to the starter motor, with consequent variations of the connector terminal. The electrical insulation of the connection between the terminal and the cables is achieved by the use of rubber caps of various shape and dimensions. An incorrect positioning of the cables can cause various disadvantages, the most serious of which is the risk of fire if the vehicle is involved in an accident, even at low speed. Moreover, the insulating caps, because of their weakness or because of incorrect assembly, are often not able to ensure the necessary protection of the connection. To ensure positioning of the cables in an unequivocal manner it has until now been necessary to use a range of connection terminals for starter motors, with evident problems and labour in production. This further involves a corresponding range of variation of the protective caps and the risk of erroneous use of one given type of cap of unsuitable shape for the connection terminal to which it is fitted. The object of the present invention is that of overcoming these disadvantages and of providing a device which makes the connection between the cables and the associated electrical apparatus easier, requiring the operator to orientate and position the cables exclusively in the connection configuration established by the design, and on the other hand guarantees a more effective electrically insulating protection of the connection. According to the invention, object is achieved by a device according to claim 1. Thanks to this arrangement, the operation of connecting the conductor cables to the connection terminal, disposing these cables in the correct orientation and lay out, is made easier and more convenient. It is, in fact, sufficient to position the base of the body on the terminal in the envisaged orientation and then engage the seat of the base itself on to the terminal, maintaining the cover in the open position. The connection ends of the conductor cables attached to the body of the device by means of the external retaining member, are then inserted through the aperture in the base and fixed in a conventional manner to the terminal by acting in the space left open by the cover. Finally, closure of the cover takes place. This cover forms an effective and stable insulating protection for the connection. The device allows a significant standardization of connection terminals for electrical apparatus which is particularly advantageous in the specific application to motor vehicle starter motors, and makes it possible for the currently used insulating cap to be dispensed with. Peferred constructional embodiments of the invention are defined by the features of the dependent claims. The invention will now be described in detail with reference to the attached drawings in which: Figure 1 is a schematic perspective view of a device according to the invention, and Figure 2 is a sectional view of the device shown in use. In the drawings, reference numeral 1 generally indicates a moulded plastics material body constituted by a base 2 and a cover 3 connected together at one end by means of an integral ligament hinge 4. The hinge allows the cover 3 to turn in relation to the base 2 between an open position shown in Figure 1 and in broken outline in Figure 2, and a closure position shown in solid outline in Figure 2. Base 2 has, on the side opposite the cover 3, a through hole 5 delimited by an annular seat 6 externally of which is associated a projection 7 of pre-determined angular extent, the function of which will be clarified hereinbelow. The base 2 further has an aperture 8 at the end adjacent to the ligament hinge 4 and is formed, close to its edge opposite the seat 6, with a series of counterposed openings 9. These openings are intended to be snap-engaged by a series of corresponding hook projections 10 formed on the edges of the cover 3 when this is turned from the open position to the closure position relative to the base 2. The reference numeral 11 indicates a resilient band element or the like connected to one side of the base 2 through an elongate element 12 which can be constituted by a rigid rod or by a flexible cable. In use the body 1 makes the connection between the conductive cables C and a connection terminal T of an electrical apparatus A easier, and makes the protection of this connection more effective. In the specific example illustrated, the apparatus A is constituted by the electromagnet of an electric starter motor for an internal combustion engine of a motor vehicle, and the cables C constitute the supply conductors from the battery (not illustrated) of the vehicle. The terminal T is constituted, in a manner known per se by a cylindrical or prismatic projection from which projects a threaded stem S intended to receive the connection end or terminal E of the cable C to allow their subsequent locking by means of a nut D. The assembly of the connecting parts is performed as follows: The body 1 is generally attached to one or both cables C by means of the band element 11, which surrounds them in a slidable manner. In this way, at a pre-assembly station to each set of cables C for a given type of vehicle, there is preliminarily associated an appropriate body 1, (suited to the shape of the hole 5, the seat 6, the associated outer projection 7, and/or the arrangement of the aperture 8) for application to a specific terminal T, or rather to a plurality of joined terminals T. The first operation consists in fitting the seat 6 of the base 2 on to the terminal T whilst maintaining the cover 3 in the open position, and orientating it according to the pre-established layout. position. This operation is facilitated thanks to the interaction between the terminal T and the outer projection 7 which functions in this way as an angular centring abutment of the body 1. The base 2 is then clamped in relation to the terminal T to effect form coupling, either forcibly or by snap engagement between the seat 6 and the terminal itself. In this way the screw S is enclosed within the base 2 through the hole 5. The subsequent operation consists in introducing the terminals E of the cables C into the base 2 through the aperture 8 by means of a sliding movement of these cables C relative to the attachment band 11. The terminals E are fitted on to the screw S and then clamped to the terminal T by means of the nut D. Finally the cover 3 is closed and locked in relation to the base 2 by the snap engagement of the projections 10 into the associated openings 9. At the end of assembly the connection between the cables C and the terminals T is effected in the correct pre-determined layout position, and the insulating protection of this connection is ensured in an effective and stable manner. The described embodiment can of course be modified without leaving the general technical concept of the invention. Thus, for example, the base 2 and the cover 3 could be constituted by two separate, distinct parts, and in this case the ligament hinge 4 would be replaced by a simple flexible connection member similar to the element 12.

Claims: A device for facilitating and protecting the connection between conductive cables (C) and associated connection terminals (T) for electrical apparatus (A), particularly the electromagnet of a motor vehicle starter motor, comprising a box-like body (1) having a base (2) and a cover (3) of electrically insulating material, the base having a seat (6) delimiting a hole (5) for engagement by form coupling on the connection terminal (T) and an aperture (8) for the introduction of conductive cables (C), the cover (3) being articulated to the base (2) so as to be turnable with respect to said base between an open position and a closed locking position, and an external retaining member (11) connected to the body (1) and attachable to the said cables (C), characterised in that the base (2) is provided with an integral abutment (7) extending from said the body (1) of a cylinder base around said hole (5) in the form of a portion less than 360°, and adapted to interact with the terminal (T); the integral abutment (7) constituting an angular centering means of the body (1) with respect to the connection terminal (T), such that, in the engaged position of the body (1) with the terminal (T), the cables (C) have a predetermined radial orientation with respect to the terminal. A device according to Claim 1, characterised in that the base (2) and the cover (3) are formed integrally of moulded plastics material and are connected together by means of a ligament hinge (4), and in that it further includes integral snap-engagement means (9, 10). A device according to any of the preceding claims, characterised in that the seat (6) of the base (2) is shaped in such a way that the body (1) may be force fitted to the connection terminal (T). A device according to any preceding claim, characterised in that the external retaining member is formed by a resilient band element (11) connected to the base (2) of the body (1) by an elongate element (12).

Inventors: SMO' LUCIANO, SPINA DONATO, SMO', LUCIANO, SPINA, DONATO
Applicants: FIAT AUTO SPA, FIAT AUTO S.P.A.
Application year: 1992
Main classification: H01R4
IPC codes: H02G3, H01R13, F02B77, H01B17, H01R4