FR2690284A1 - Mfg. electric circuit board with integral connection device for motor vehicle - involves drilling holes in particular range and second set of holes related to first set and electrically connecting them by electrical conductors - Google Patents

Abstract

The method is for forming an electric circuit board (10) or printed circuit board from flat insulating material (12) with various tracks of electrical contacts. The board can be single or double-sided, that is the electrical contacts may be on one or both sides. A V-shaped groove is made into the board (16) and a series of holes (18) are made in the board. The number of holes are equal to the number of electrical connections required. The holes are aligned with the edge of the groove. A second series of holes (20) are formed equal to the number of holes in the first series. The first and second series of holes form pairs and are perpendicular to the groove. The second series of holes are disposed alternatively in parallel. Electrical conductors (50) link the first and second sets of holes and are affixed automatically. The ends of the connectors are bent (56,58) according to the required use. USE - Electrical connection on printed circuit boards for use in automotive vehicle electrical assemblies, esp. clocks.

Description

 The present invention relates to the field of electrical circuit boards, very preferably electrical circuit boards made on the basis of printed circuits.

 The present invention finds particular, but not exclusively, application in the production of electrical assemblies for motor vehicles, in particular watches.

 Numerous electrical circuit boards have already been proposed comprising connection means.

 The object of the present invention is to propose a method making it possible to obtain an electrical circuit board comprising integrated connection means authorizing a connection on the edge of the board.

 This object is achieved according to the present invention by a method which comprises the steps consisting in i) making in a circuit board, a first series of holes aligned in a row, ii) making in the board a second series of holes in number equal to said first series of holes, opposite the respectively associated holes of the first series, iii) engaging individual electrically conductive elements, in the general form of jumpers, in the pairs of holes respectively associated with the first and second series of holes, and iv) sectioning the wafer along a general line coinciding at least substantially with the center of the holes of the first series, so as to make accessible at this level the electrically conductive elements on the edge of the wafer.

 The present invention also relates to the wafer thus obtained.

 Other characteristics, objects and advantages of the present invention will appear on reading the detailed description which follows, and with reference to the appended drawings given by way of nonlimiting examples and in which - Figure 1 illustrates, in the form of 'flow chart, the method according to the present invention, - Figure 2 is a perspective view illustrating the sectioning step according to the present invention, - Figure 3 is a second partial perspective view of an electrical circuit board according to the present invention, - Figure 4 shows a view of a conductive element in the form of a jumper before insertion on a circuit board, and - Figure 5 shows the same conductive element after folding.

 The present invention uses an electrical circuit board 10, more specifically, preferably, a printed circuit board.

 In a manner known per se, such a plate 10 comprises a generally flat support made of electrically insulating material 12 coated with various tracks 14 made of electrically conductive material.

 The support plate 12 and the electrically conductive tracks 14 can be produced according to any technique known to those skilled in the art.

 The plate 10 can be formed of a single or double-sided printed circuit, that is to say that one can provide electrically conductive tracks 14 on one side of the support 12, or on both sides thereof.

 We will now describe the preferred method according to the present invention with reference to Figure 1 attached.

 FIG. 1 schematizes an initial step 100 consisting in making a straight groove in the plate 10.

 It is preferably a V-shaped section groove with a depth substantially equal to half the thickness of the plate 10, as shown in FIG. 2 under the reference 16.

 The step referenced 102 in FIG. 1 consists in making a first series of holes 18 in the plate 10. The different holes 18 are equal in number to the number of electrical connections desired between the plate 10 and the surrounding means.

 The holes 18 are moreover aligned in a row which coincides with the bottom of the groove 16, as seen in FIG. 2.

 Step 104 represented in FIG. 1, consists in making a second series of holes in the plate 10. The holes in this second series are referenced 20.

They are equal in number to holes 18 of the first series.

 Furthermore, the holes 20 of the second series are arranged respectively opposite the holes 18 of the first series.

 The holes 18 of the first series, and the holes 20 of the second series are thus associated in pairs, and each associated pair of holes 18, 20, extends in a general direction perpendicular to the groove 16.

 Furthermore, it will be noted that the holes 20 of the second series are arranged alternately in two rows parallel to the row of holes 18 of the first series and located at different distances from this first row of holes 18.

 The holes 20 of the second series are located on the same side of the holes 18 of the first series.

 The alternate arrangement of the holes 20 makes it possible to reduce the pitch of the tracks 14 provided on the wafer 10.

 In FIG. 1, the three aforementioned steps are represented in the following successive order: 100, 102, 104.

However, in practice, the order of these three preliminary steps can be arbitrary. Steps 102 and 104 can be performed simultaneously.

 Step 100 can be carried out between steps 102 and 104, or even after steps 102 and 104.

 Once the groove 16 and the holes 18 and 20 have been made in the wafer 10, the method according to the present invention comprises the step 106 consisting in implanting on the wafer electrically conductive elements 50 of the type shown in FIG. 4.

 More specifically, these are conductive elements in the general form of jumpers. Each conductive element 50 thus has the general shape of a U comprising a core 54 and two wings 56, 58. The wings 56, 58 are parallel to each other and orthogonal to the core 50.

 One of the wings 56 is engaged in a hole 18 and the second wing 58 is engaged in the associated hole 20.

 Of course, it is necessary for this purpose to have two series of jumpers having wings 56, 58, of equal length, but webs 54 of different lengths, adapted respectively to the centers between the holes 18 and 20.

 In the implanted position, the core 54 of the jumpers 50 extends in a general direction orthogonal to the groove 16.

 The implantation of the elements 50 on the wafer 10 is preferably carried out automatically using an automaton. The jumpers 50 can be powered from a coil.

 The implantation step 106 is preferably followed by the step 108 of folding the end of the wings 56, 58, of the elements 50.

 More specifically, as shown in Figure 3 and Figure 5, preferably the wings 56 and 58 are folded at the end in a common direction.

 In other words, the end of the wing 56 is folded in the direction of the wing 58, while the end of the wing 58 is folded away from the wing 56.

 The final shape of the folded element 50 is shown in FIG. 5.

 However, as a variant, provision can be made to bend the ends of the wings 56, 58 in opposite directions, one towards the other.

 Preferably, step 110 is then carried out to weld at least one of the ends of the wings 56, 58, of the elements 50.

 In Figure 3, there is shown the two ends of the wings 56, 58, welded to tracks 14 respectively associated.

 The welding of the ends of the wings 56, 58 allows them to be held firmly on the wafer 10.

 We can then proceed to the final step 112 of cutting the wafer 10 at the level of the groove 16, as shown schematically in FIG. 2.

 As shown in FIGS. 2 and 3, a plate 10 is then obtained, comprising a series of electrically conductive elements 50 projecting from the edge of the plate 10, and capable of being connected at this level to a connection element. adapted.

 It will be understood that the relative position defined between the groove 16 and the row of orifices 18 makes it easy to determine the protruding amplitude of the conductive elements 50 on the edge of the wafer 10. These conductive elements 50 protrude by half their diameter on the edge of the plate 10 when the axis of the holes 18 is centered on the bottom of the groove 16. To provide a more or less significant amplitude in projection of the conductive elements 50 on the edge of the plate 10, it suffices to offset the axis of the holes 18 relative to the bottom of the groove 16.

 The circuit element referenced 30 in FIG. 2, located on the side of the groove 16 opposite the elements 50 can be formed either of a strip of small width discarded after sectioning of the plate 10 along the groove 16, or d 'an adjacent circuit board itself having, at its opposite end, a series of electrically conductive elements 50.

 The present invention can, of course, find many applications.

 According to a preferred application, it is used to produce electrical assemblies for motor vehicles, cards for dashboards of motor vehicles, where appropriate electric watches.

 In this case, the plate 10 having the electrically conductive elements 50 projecting from its edge is preferably placed opposite a connection element of the type sold under the name "ZEBRA".

 Such a connection device is well known to those skilled in the art. It is essentially formed by a stack of layers of elastomeric or equivalent materials which are alternately conductive and non-conductive.

 Of course the present invention is not limited to the particular embodiment which has just been described but extends to any variant in accordance with its spirit.

Claims (10)

 1. Method for producing an electrical circuit board, characterized in that it comprises the steps consisting in i) making in a circuit board (10) a first series of holes (18) aligned in a row, ii ) making a second series of holes (20) in the plate (10) equal in number to said first series of holes (18), opposite the respectively associated holes (18) of the first series, iii) engaging individual elements electrically conductors (50) in the general shape of jumpers, in the pairs of holes respectively associated (18, 20) of the first and of the second series of holes, and iv) cutting the plate (10) along a general line (16) coinciding at least substantially with the center of the holes (18) of the first series, to thereby make accessible at this level the electrically conductive elements (50) on the edge of the wafer (10).  2. Method according to claim 1, characterized in that it further comprises the step consisting in producing a groove (16) in the plate (10) substantially aligned on the axes of the holes (18) of the first series, and that step iv) consists in cutting the wafer at the level of the groove (16).  3. Method according to claim 2, characterized in that the groove (16) has a cross section in the general shape of V.  4. Method according to one of claims 1 to 3, characterized in that the second series of holes (20) is arranged alternately in two rows located at different distances from the first row of holes (18) and parallel to that -this.  5. Method according to one of claims 1 to 4, characterized in that the implantation of the electrically conductive individual elements (50) is carried out using an automatic machine in step iii).  6. Method according to one of claims 1 to 5, characterized in that it further comprises the step of welding at least one of the ends of the electrically conductive elements (50) after step iii) and before the sectioning stage iv).  7. Electric plate obtained using the method according to one of claims 1 to 6 and comprising electrically conductive elements (50) projecting from the edge (10) of the plate.  8. Application of the plate according to claim 7 to the production of electrical assemblies for motor vehicles.  9. Application according to claim 8, comprising a connection device comprising a stack of layers of elastomeric or equivalent materials alternately conductive and non-conductive placed opposite the edge of the wafer (10).  10. Application according to one of claims 8 or 9, characterized in that the plate is integrated in a card for dashboard of motor vehicles.