FR2995458A1 - METHOD FOR MANUFACTURING A CONNECTING DEVICE FOR CRIMPING ON A TERMINAL STRIP DENUDE OF ELECTRIC CABLE AND SUCH DEVICE FOR CONNECTING - Google Patents

Abstract

The invention relates to a method for manufacturing a crimp connection device on a stripped end section of electric cable, comprising the step of providing a conductive element (7) made in one piece and having a tubular portion (13). an introduction opening through which it is intended to introduce into said tubular portion (13) said stripped end portion and a flat portion (15) configured to cooperate with a predetermined electrical terminal, said tubular portion (13) being connected, at an end opposite said insertion opening, by a transition portion (14), to said flat portion (15); said method comprising a step of deforming said transition portion (14) until said transition portion (14) forms a substantially straight bottom wall of said tubular portion (13), wherein said bottom wall extends substantially perpendicular to said tubular portion (13).

Description

The invention relates to methods of manufacturing a crimp connection device on a terminal section stripped of an electric cable. The invention also relates to such connection devices crimped on a terminal section stripped of an electric cable. It is already known, in particular from the European patent application EP 2 273 618, such a method and such a device, which comprises a conductive element having a tubular portion, an introduction opening through which it is intended to introduce into the portion tubular the bare terminal section and a flat portion configured to cooperate with a predetermined electrical terminal, the tubular portion being connected at an end opposite the introduction opening, a transition portion, the flat portion. The method includes the step of providing a conductive cylindrical tube having a predetermined diameter and having the tubular portion and the introduction opening. The method further comprises the step of flattening the cylindrical tube at one end of the cylindrical tube opposite to the introduction opening so as to form the flat portion as well as the transition portion, which is thus inclined, connecting the portion tubular to the flat portion. The transition portion thus forms a bottom wall, which is inclined relative to the flat portion, of the tubular portion of the device.

The invention aims to provide a method of manufacturing a connection device of the same kind, which is particularly simple, convenient and economical to implement. The invention thus provides, in a first aspect, a method of manufacturing a crimp connection device on a stripped end section of electric cable, comprising the step of providing a conductive element made in one piece and having a tubular portion extending in a longitudinal general direction, an insertion opening through which it is intended to introduce into said tubular portion said stripped end portion and a flat portion configured to cooperate with a predetermined electrical terminal, said tubular portion being connected at an end opposite said insertion opening by a transition portion to said flat portion; said method being characterized in that it further comprises a step of deforming said transition portion until said transition portion forms a substantially straight bottom wall of said tubular portion, wherein said bottom wall extends substantially perpendicular to said longitudinal general direction of said tubular portion.

In its initial state, the bottom of the transition wall had an inclined orientation. The bottom wall is thus derived from the straightening of the bottom of the transition portion during the deformation step. The tool having made the rectification of the bottom of the transition portion leaves on the bottom wall a flat area, generally of length at least equal to one third of the diameter of the bottom wall. Note that it is here considered that the bottom wall extends substantially perpendicular to the longitudinal direction of the tubular portion when a flat area of at least one third of the diameter of the bottom wall has an angle with respect to the longitudinal direction of the tubular portion in the range [80 °; 100 °]. The method according to the invention makes it possible to offer, thanks to the deformation step, a good reproducibility of the configuration of the conductive element of the connection device. Indeed, the transition portion is always deformed, in a controlled manner, until the latter forms the substantially straight bottom wall of the tubular portion, where the bottom wall still extends substantially perpendicular to the longitudinal direction. of the tubular portion, in contrast to the inclined transition portion of the conductive member of the aforementioned prior art connecting device. The method according to the invention thus allows the stripped terminal section of the electric cable to be positioned with good reproducibility (in other words always in the same predetermined position) in the tubular portion of the conductive element of the connection device, contrary to the aforementioned prior art where the stripped end section of the electric cable is more or less depressed in the tubular portion due to the inclination of the transition portion.

It will be noted that the straight form of the bottom wall ensures the abutment positioning against the latter of the bare terminal section of the electric cable. The method according to the invention is therefore particularly efficient while remaining particularly simple, convenient and economical to implement. According to preferred, simple, convenient and economical characteristics, the assembly method according to the invention further comprises the following steps: providing a conductive cylindrical tube having a first predetermined internal diameter and having said insertion opening; at least partially expanding said conductive cylindrical tube to form said tubular portion, which is provided with at least one first tubular section having a second internal diameter greater than said first predetermined internal diameter. By virtue of the step of expanding the conductive cylindrical tube to form the tubular portion, the method according to the invention advantageously makes it possible to be able to insert an electric cable of relatively high predetermined diameter while having a conductive element manufactured from a conductive cylindrical tube whose inner diameter is configured to provide a relatively small flat portion, particularly in width. According to other preferred features, simple, convenient and economical, the assembly method according to the invention: - said deformation and expansion steps are performed at the same time by inserting a deformation and expansion pin in said 30 insertion opening of said conductive cylindrical tube; said method comprises the step of flattening said cylindrical tube at one end of said cylindrical tube opposite to said insertion opening so as to form said flat portion as well as said transition portion connecting said tubular portion to said flat portion; said method comprises the step of deforming said tubular portion so as to form an annular shoulder near said transition portion; said method comprises the step of drilling said flat portion so as to form an orifice configured to receive a fastener of said predetermined electrical terminal; said connecting device further comprises a sleeve configured to be disposed inside said tubular portion and in which it is intended to introduce said bare end section, said sleeve comprising a plurality of perforations and being made of a harder material; aluminum so that said sheath is configured to deform said stripped end portion with said aluminum conductive core which is configured to be embedded in said perforations of said sheath; said method further comprising the steps of providing said sheath and introducing it at least partially into said tubular portion; whereby said connecting device is suitable for said electrical cable which comprises a conductive aluminum core. said method comprises the step of introducing a predetermined quantity of contact grease into said tubular portion against said substantially straight bottom wall; and / or - said method comprises the steps of providing a plug and mounting it on said tubular portion at said insertion opening.

The invention also has, in a second aspect, a connection device to be crimped on a terminal section stripped of electrical cable, comprising a conductive element made in one piece and having a tubular portion, an insertion opening through which it is planned to introduce into said tubular portion said stripped end portion and a flat portion configured to cooperate with a predetermined electrical terminal, said tubular portion being connected, at an end opposite said insertion opening, by a transition portion, said flat portion; said device being characterized in that said transition portion is deformed so as to form a substantially straight bottom wall of said tubular portion, wherein said bottom wall extends substantially perpendicular to said longitudinal general direction of said tubular portion. In its initial state, the bottom of the transition wall had an inclined orientation. The bottom wall is thus derived from the straightening of the bottom of the transition portion during the deformation step. The tool having made the rectification of the bottom of the transition portion leaves on the bottom wall a flat area, generally of length at least equal to one third of the diameter of the bottom wall. Note that it is here considered that the bottom wall extends substantially perpendicular to the longitudinal direction of the tubular portion when a flat area of at least one third of the diameter of the bottom wall has an angle with respect to the longitudinal direction of the tubular portion in the range [80 °; 100 °]. The connection device according to the invention has, thanks to the substantially straight bottom wall of the tubular portion of its conductive element, which bottom wall is derived from the deformation of the transition portion, a good reproducibility of the configuration of its conductive element. Indeed, the transition portion is always deformed, in a controlled manner, to form the substantially straight bottom wall of the tubular portion, where the bottom wall still extends substantially perpendicular to the longitudinal direction of the tubular portion, contrary to the inclined transition portion of the conductive element of the aforementioned prior art connecting device. The stripped end section of the electric cable can therefore be positioned with good reproducibility (in other words always in the same predetermined position) in the tubular portion of the conductive element, unlike the aforementioned prior art where the bare terminal section of the electric cable is more or less depressed in the tubular portion due to the inclination of the transition portion.

It will be noted that the straight form of the bottom wall ensures the abutment positioning against the latter of the bare terminal section of the electric cable. The connection device according to the invention is therefore particularly powerful while remaining particularly simple, convenient and economical. According to preferred, simple, convenient and economical characteristics, said tubular portion of the assembly according to the invention comprises a first tubular section formed by expansion and having a second internal diameter, which first tubular section has a length equal to or greater than said second internal diameter. By virtue of the first expanded tubular portion of the tubular portion, the connection device according to the invention advantageously makes it possible to be able to insert a relatively high-diameter electrical cable of predetermined diameter while having a conductive element manufactured from a cylindrical conducting tube 15 whose inner diameter is configured to provide a relatively small flat portion, particularly in width. According to preferred, simple, convenient and economical features of the device according to the invention: said tubular portion comprises an annular shoulder near said substantially straight bottom wall; said first tubular section is formed between said insertion opening and said shoulder, and said tubular portion further comprises a second tubular section between said shoulder and said substantially straight bottom wall, which second tubular section has a first predetermined internal diameter. less than said second predetermined internal diameter of said first tubular section; said second tubular section has a length less than said first internal diameter; said flat portion is provided with an orifice configured to receive a fastener of said predetermined electrical terminal; said device is configured to be crimped on an electric cable provided with an aluminum conductive core and that it further comprises a sleeve disposed inside said tubular portion and in which it is intended to introduce said terminal section; denuded, said sheath having a plurality of perforations and being made of a material harder than aluminum so that said sheath is configured to deform said stripped end portion, with said aluminum conductive core which is configured to be embedded in said perforations of said scabbard ; said device further comprises a predetermined quantity of contact grease in said tubular portion, against said substantially straight bottom wall; and / or - said device further comprises a plug mounted on said tubular portion at said insertion opening. We will now continue the description of the invention by the description of an exemplary embodiment, given below by way of illustration and not limitation, with reference to the accompanying drawings in which: - Figure 1 shows schematically a vehicle starter here, a vehicle of the heavyweight type, connected to a battery of this vehicle via at least one assembly according to the invention; FIG. 2 is an isolated perspective view of a connecting lug according to the invention, as received in an assembly workshop of the assembly, visible in FIG. 1, the connection lug being then equipped with a protective cap; FIG. 3 is a view in median section of the terminal of FIG. 2; FIG. 4 is a perspective view of the terminal visible in FIGS. 2 and 3 and of a deformation pin used to shape a bottom wall of this terminal; - Figure 5 is a sectional view of the terminal visible in Figures 2 and 3, after expansion of the bottom wall, with the deformation pin still inserted into the pod; Figure 6 is a partial exploded perspective view of the terminal visible in Figures 2 and 3 showing a conductive element and a perforated sheath; - Figure 7 is a partial perspective view of the lug visible in Figures 2 and 3, and an electric cable away from the lug and provided with a denuded terminal section; - Figure 8 is a sectional view of the pod visible in Figure 7, with the bare end section introduced into the pod; - Figure 9 is a view similar to Figure 8, but showing schematically a crimping device configured to crimp several areas of the terminal on several portions of the bare end section of the electric cable; FIG. 10 is a view similar to FIG. 8, but schematically showing a punching device configured to punch an area of the terminal on a portion of the bare terminal section of the electric cable, to form the assembly visible in FIG. 1; - Figure 11 is a partial perspective view of the assembly visible in Figure 1; - Figure 12 is a partial sectional view of the assembly visible in Figure 11; - Figure 13 is a sectional view marked XIII-XII I in Figure 12, showing a first zone of the lug crimped on a first portion of the bare end section of the electric cable; FIG. 14 is a sectional view marked XIV-XIV in FIG. 12, showing a second zone of the terminal crimped on a second portion of the bare terminal section of the electrical cable; and FIG. 15 is a sectional view marked XV-XV in FIG. 12, showing a third zone of the terminal punched on a third portion of the bare terminal section of the electrical cable. FIG. 1 schematically represents a motor vehicle 100 of the heavy truck type, comprising a starter 5 configured to launch a ring of a heat engine (not shown) of the vehicle 100, which starter 5 is formed by a rotating electrical machine connected to a battery 2 by means of an electrical connection assembly 1. The electrical connection assembly 1 is here provided with two connection lugs 3 and an electric cable 4 with a conductive core 35 of aluminum (FIG. 7). ) on which are integrally assembled the two connection lugs 3. The conductive core 35 here comprises a plurality of strands (Figure 8) of aluminum. The cable 4 has two opposite ends each forming a stripped terminal section 6 (FIG. 7) where the lugs 3 are crimped and punched. The lug 3 will be described in detail with reference to FIGS. 2 and 3, in which a protective plug 8 is mounted on this lug 3. The lug 3 comprises a conductive element 7 and a metallic tubular insert monobloc 9. The conductive element 7 comprises a tubular portion 13 extending in a longitudinal general direction, a flat portion 15 connected to the tubular portion 13 by a transition portion 14 and an insertion opening 16 opposite the portion Transition 14. The tubular portion 13 is hollow and provided with an outer face 18 and an inner face 19, which defines an internal space 20 of the tubular portion 13. The tubular portion 13 further comprises a first tubular section 22 having a large internal diameter, also called second internal diameter, a second tubular section 23 having a small internal diameter, also called first internal diameter, which is smaller than the second internal diameter, and an annular shoulder 17 connecting the first tubular section 22 at the second tubular section 23. The first tubular section 22 is located between the annular shoulder 17 and the introductory opening 16. The second tubular section 23 is located between the annular shoulder 17 and the transition portion 14.

The second tubular section 23 here has a length less than the first internal diameter and the first tubular section 22 here has a length greater than the second internal diameter. The tubular portion 13 comprises an insertion chamfer 24 formed on the first tubular section 22, at the insertion opening 16. The transition portion 14 connects the second tubular section 23 of the tubular portion 13 to the flat portion 15. This transition portion 14 forms a bottom wall of the tubular portion 13, which bottom wall has an inner face 21 facing the inner space 20. The bottom wall is here straight, substantially perpendicular to the longitudinal general direction of the tubular portion 13 and substantially perpendicular to the flat portion 15.

The flat portion 15 forms a mechanical and electrical contact pad configured to cooperate with a predetermined electrical terminal (not shown). This predetermined electrical terminal belongs here to either the battery 2 or the starter 5.

The flat portion 15 has a generally parallelepipedal shape, has a predetermined width, and is provided with a hole 12 formed centrally and configured to receive a fastener (not shown), for example a bolt having a screw and a nut. Note that this bolt belongs, in one case to the battery 2 and 25 in the other case to the starter 5. The one-piece tubular insert 9 comprises a sheath 32 and a flared ring 39 located at one end of the sheath 32. The sheath 32 is located in the inner space 20 of the tubular portion 13, at the first tubular portion 22. The sleeve 32 has a slotted body 60 having a generally cylindrical shape (Figure 6).

The body 60 has an outer diameter (when the body 60 is subjected to no stress) substantially similar or slightly greater than the second internal diameter of the first tubular section 22 of the tubular portion 13 (Figure 6).

The body 60 has an inner face 33 and an outer face 34, which comes into contact with the inner face 19 of the tubular portion 13. The body 60 is mounted slightly compressed in the internal space 20 of the tubular portion 13 (due to slot). The sheath 32 also has a plurality of perforations 59 made in the body 60. It will be noted that this sheath 32 is configured to deform the stripped end portion 6 with the conductive core 35 (FIG. is embedded in these perforations 59 (see below). The flared collar 39 is located at the end of the sleeve 32 in close proximity to the introduction opening 16 and thus to the insertion chamfer 24. The flared collar 39 has a profile similar to that of the introduction chamfer 24 against which this flared ring 39 comes to bear. It will be noted that the flared ring 39 delimits the introduction opening 16 of the conductive element 7. It will furthermore be noted that the flared ring 39 is configured to facilitate the introduction of the stripped terminal section 6 of the cable 4 into the internal space 20 of the tubular portion 13. A predetermined amount of contact grease 10 is introduced into the inner space 20 of the tubular portion 13 at and against the bottom wall thereof. This contact grease 10 is configured to improve the electrical conductivity between the conductive core 35 (FIG. 7) made of aluminum of the cable 4, the insert 9 and the conductive element 7. The plug 8 is mounted on the external face 18 of the tubular portion 13, at the first tubular section 22 and facing the opening opening 16, so as to plug the internal space 20 of the tubular portion 13. We will now describe the 3. The conductive element 7 is made from an initial metal cylindrical tube having a predetermined internal diameter corresponding to the first internal diameter of the second tubular section 23 of the tubular portion 13. Two opposite walls of the cylindrical tube are flattened (brought closer together until contacting) at an end opposite to the insertion opening 16 so as to form the flat portion 15. This flattened portion issement creates a first configuration of the transition portion 14 (inclined orientation of the bottom wall) and thus closes the internal space 20 on the opposite side to the introduction opening 16. Next, the tubular portion 13 is formed by expansion over a predetermined length to form, firstly the first tubular section 22 having the second internal diameter, and secondly the annular shoulder 17 (on the inner face 19), which shoulder thus delimits the first and second sections 22 and 23 of the tubular portion 13. Then, the transition portion 14 is deformed so that the bottom wall of the tubular portion 13 is straightened from the inclined orientation it had at the end of the step of flattening to the right orientation visible on the drawings. These deformations are made with a deformation spindle 25 (FIGS. 4 and 5), here an expansion spindle, configured to be introduced into the internal space 20 of the tubular portion 13 by its insertion opening 16. These deformations are furthermore made with a matrix (not shown) configured so that the tubular portion 13 is sandwiched between this matrix and the expansion pin 25. The matrix therefore applies to the outer face 18 of the tubular portion 13 .

This expansion pin 25 comprises a body provided with a first cylindrical portion 26 having a first outer diameter greater than the second internal diameter of the first tubular section 22, a second cylindrical portion 27 having a second similar external diameter (at the introductory game near) to the second inner diameter of the first tubular section 22 and a third cylindrical portion 28 having a similar third outer diameter (to the introductory clearance near) to the first inner diameter of the second tubular section 23. The first cylindrical portion 26 is connected to the second cylindrical portion 27 by a first annular shoulder 29 and the third cylindrical portion 28 is connected to the second cylindrical portion 27 by a second annular shoulder 30. The third cylindrical portion 28 has at its end which is the opposite side to the side connected to the second shoulder 30, a face 31 which is flat. It will be noted that the second cylindrical portion 27 together with the first annular shoulder 29 have substantially the same length as the length of the tubular insert 9. It will further be noted that the second shoulder 30 is configured to form, together with the matrix, the shoulder 17 of the tubular portion 13. It will also be noted that the flat face 31 is configured to form the inner face 21 of the bottom wall of the tubular portion 13. The deformation step by expansion with the pin 25 is carried out by introducing this pin 25 with the second cylindrical portion 27 which comes into contact with the inner face 19 at its first tubular portion 22 to expand the latter, with the shoulder 29 which comes into contact with the inner face 19 in the vicinity of the insertion opening 16 to create the insertion chamfer 24, with the shoulder 30 which forms the shoulder 17, and with the flat face 31 which comes against the portion of t ransition 14 to straighten it and thus form the right bottom wall and thus the inner face 21.

The conductive element 7 is therefore mainly formed by deformation and expansion of the initial cylindrical tube via the expansion pin 25 and the die (not shown). It should be noted that the expansion pin 25 leaves on the bottom wall 21 a flat zone, generally of length at least equal to one third of the diameter of the bottom wall 21 (see the part of the face 31 in contact with the wall bottom 21 in Figure 5). Recall that it is here considered that the bottom wall 21 extends substantially perpendicular to the longitudinal direction of the tubular portion 13 when a flat area of at least one third of the diameter of the bottom wall 21 has an angle with respect to the longitudinal direction of the tubular portion 13 in the range [800; 1001. The one-piece tubular insert 9 (provided with the sheath 32 and the flared ring 39) is then supplied and introduced into the internal space 20 of the tubular portion 13 through the insertion opening 16. It will be noted that the introduction of this insert 9 is facilitated by the introduction chamfer 24. The insert 9 is introduced until it comes into abutment on the annular shoulder 17, and with the flared ring 39 which takes place in the chamfer 20 of FIG. introduction 24. The inner face 19 of the tubular portion 13 is opposite the outer face 34 of the sleeve 32. A predetermined quantity of contact grease 10 is introduced into the internal space 20 against the inner face 21. As it is 7, the electric cable 4 further comprises a conductive core 35 provided with a plurality of aluminum strands, an insulating sheath 36 of a predetermined thickness enveloping the conductive core 35. The electric cable 4 comprises an isolated section 37, provided u of the core 30 and the sheath 36, and a stripped end section 6 located at the end of the isolated section 37, which stripped end section 6 is devoid of sheath 36.

The stripped end section 6 has a substantially flat end face 38 opposite the insulated section 37. We will now describe in detail the assembly 1 comprising the lug 3 integrally assembled with the stripped terminal section 6 of the electric cable 4, with reference to FIGS. 11 to 15. The tubular portion 13 has, along what was initially its first tubular section 22 located between the insertion opening 16 and the annular shoulder 17, a first crimped zone 40, a second crimped area 41 and a third punched area 42.

The first zone 40 is furthest from the introduction opening 16 while the second zone 41 is closest to it. The third zone 42 is located between the first zone 40 and the second zone 41. The denuded terminal section 6 has a first portion 43 at a distance from the introduction opening 16, a second portion 44 near this opening 16 and a third portion 56 located between the first portion 43 and the second portion 44. The first zone 40 is crimped on the first portion 43, which has a first compression ratio, also called section reduction rate (TRS).

This first compression ratio is here in the range [10%; 30%]. Note that this is an average compression ratio. It will also be noted that the compression ratios (or section reduction ratio) are here calculated by the following relationship: r TRS (%) ---- 1-- x100; with: - A: the sum of the sections of the strands of the conductive core 35, before crimping and / or punching, in mm 2; and B: the sum of the sections of the strands of the conductive core 35, after crimping and / or punching, in mm 2 (excluding the spaces created between the crimped and punched strands).

As illustrated in FIG. 13, the first zone 40 and the first portion 43 have, in section, a general shape in B. It will be noted that the compactness of the assembly formed of the first zone 40 and crimped portion 43 here has a perimeter ratio external P of these area and portion on height H the smallest passing through the center of gravity G (here the geometric center) of these area and portion, which is less than about 6, significant of a first crimping. Here, it is considered that when a zone or portion has a ratio of less than 6, it is in the presence of crimping.

The second zone 41 is crimped on the second portion 44, which has a second compression ratio which is lower than the first compression ratio. This second compression ratio is here in the range [2%; 20%]. Note that this is a low compression ratio.

As illustrated in FIG. 14, the second zone 41 and the second portion 44 have, in section, a hexagonal shape. It will be noted that the compactness of the assembly formed of the second zone 41 and crimped portion 44 here has an external perimeter ratio P of these zone and portion on height H the smallest passing through the center of gravity G (here the geometric center) of these area and portion, which is less than about 6, significant of a second crimping. The third zone 42 is punched with the third portion 56, which has a third compression ratio which is greater than the first and second compression ratio.

This third compression ratio is here in the range [25%; 45%]. Note that this is a strong compression ratio. As illustrated in FIG. 15, the third punched zone 42 and the third portion 56 have, in section, a crescent shape. It will be noted that the compactness of the assembly formed of the third zone 42 and the portion 56 punched here has an external perimeter ratio P of these zone and portion on height H the smallest passing through the center of gravity G (here the geometric center) of these area and portion, which is greater than about 6, significant of a punching. Here it is considered that when a zone or portion has such a ratio greater than or equal to 6, it is in the presence of punching.

We will now describe the integral assembly method of the assembly 1 with reference to Figures 8 to 10. Only the bare terminal section 6 of the cable 4 is introduced through the insertion opening 16 in the pod 3, the isolated section. 37 facing this introductory opening 16.

It will be noted that the introduction of this stripped end portion 6 into the terminal 3 is facilitated by the flared ring 39. The stripped end portion 6 is inserted into the terminal 3 until the end face 38 of the cable 4 comes facing the inner face 21 of the bottom wall of the tubular portion 13.

A layer of contact grease 10 separates this inner face 21 from the end face 38. The right bottom wall of the tubular portion 13 allows, once the end face 38 of the cable 4 facing the inner face 21 of this tubular portion 13, to return with a good distribution a portion of the contact grease 10 around the first, second and third portions 43, 44 and 56 of the stripped end portion 6. The conductive core 35 has a diameter substantially equal to first internal diameter of the second tubular section 23 which guides the denuded terminal section 6 in the internal space 20.

The first zone 40 and the second zone 41 of the first tubular section 22 of the tubular portion 13 are crimped in a single step respectively on the first and second portions 43 and 44 of the stripped end portion 6, by means of a single crimping device 45 configured to obtain distinct compression ratios of the crimped strands of the stripped end portion 6. This crimping device 45 has a first lower jaw 46, a first upper jaw 47 facing the first lower jaw 46, a second lower jaw 49 distinct from the first lower jaw 46 and a second upper jaw 50 distinct from the first upper jaw 47 and opposite the second lower jaw 49.

The first lower jaw 46 and the first upper jaw 47 form a first pair of crimping jaws 46, 47, while the second lower jaw 49 and the second upper jaw 50 form a second pair of crimping jaws 49, 50. The first a pair of crimping jaws 46, 47 has a B-shaped recess and is disposed plumb with the outer face 18 of the tubular portion 13, with the B-shaped recess facing the first tubular section 22, close to the shoulder 17 (in other words away from the insertion opening 16). This first pair of crimping jaws 46, 47 is configured to crimp the first zone 40 of the tubular portion 13 to the first portion 43 of the stripped end portion 6 according to first predetermined crimping parameters so as to provide the first portion 43 the first predetermined compression ratio, and to provide to the first zone 40 and portion 43, in section, a B-shape. The second pair of crimping jaws 49, 50 has a hexagonal-shaped imprint and is disposed at the aplomb of the outer face 18 of the tubular portion 13, with the hexagonal-shaped fingerprint facing the first tubular section 22, near the introduction opening 16 (in other words away from the shoulder 17 ). This second pair of crimping jaws 49, 50 is configured to crimp the second zone 41 of the tubular portion 13 on the second portion 44 of the stripped end portion 6 according to second predetermined crimping parameters so as to provide the second portion 44 the second predetermined compression ratio (lower than the first compression ratio), and to provide the second zone 41 and portion 44, in section, a hexagonal shape.

The third zone 42 of the first tubular section 22 of the tubular portion 13 is then punched with the third portion 56 of the stripped end section 6, by means of a punching device 51 configured to obtain a strong compression ratio of the punched strands of the bare terminal section. 6. This punching device 51 comprises a punch 52 and a punching die 53 opposite the punch 52. The punch 52 and the die 53 have a crescent-shaped punching footprint and are arranged vertically in line with the external face. 18 of the tubular portion 13, with the crescent shaped recess facing the first tubular section 22, between its first and second zones 40 and 41. This punch 52 and this matrix 53 are configured to punch the third zone 42 of the tubular portion 13 on the third portion 56 of the stripped end section 6 according to predetermined parameters of punching so provided r at the third portion 56 the third predetermined compression ratio (greater than the first and second compression ratio), and to provide the third zone 42 and portion 56, in section, a crescent shape.

It will be noted that the sleeve 32 is crushed by the crimping and punching steps on the stripped end portion 6, which is thus deformed and the conductive core 35 is embedded in the perforations 59 of the sleeve 32. It will be noted that these crimping parameters and / or punching are defined in particular by the closing edge of the crimping devices 25 and / or punching 45 and 51 and the shape of the imprints thereof. These parameters of course also depend on the diameter of the conductive core 35 of the electric cable 4. As a variant, this deformation step of the transition portion is not implemented; and the invention relates to a method of manufacturing a crimp connection device on a stripped terminal section of an electric cable, comprising the step of providing a conductive element made in one piece and having a tubular portion, a crimped opening which introduction is intended to introduce into said tubular portion said stripped end portion and a flat portion configured to cooperate with a predetermined electrical terminal, said tubular portion being connected at an end opposite said opening. introducing, by a transition portion, said flat portion; said method comprising the step of providing a conductive cylindrical tube having a predetermined first internal diameter and having said introduction opening, and the step of at least partially expanding said conductive cylindrical tube to form said tubular portion, which is provided at least a first tubular section having a second internal diameter greater than said first predetermined internal diameter. In non-illustrated variants: the first zone and the second zone of the first tubular section of the tubular portion are crimped respectively on the first and second portions of the stripped end section, in two successive steps rather than in a single step, thanks to a single crimping device or two separate crimping devices; the two crimps and the punching are implemented by the same device at the same time or successively; The first zone and the second zone of the first tubular section of the tubular portion are crimped onto the first and second portions of the stripped end section and the crimped assemblies have, in section, a hexagonal shape and B; the first zone and the second zone of the first tubular portion of the tubular portion are crimped onto the first and second portions of the bare end section and the crimped assemblies both have, in section, a B-shaped or hexagonal shape; the third zone is punched with the third portion of the bare end section and the punched assembly has, in section, a shape different from a crescent, for example a star shape or an H shape; - The insert is introduced into the tubular portion of the pod at the same time as the manufacture of the latter, with the flared ring which is already formed or only preformed, and, where appropriate, the flared ring is finished to form against the introduction chamfer, by the expansion pin; - The connecting device that forms the connecting lug is replaced by another connection device, for example a connection connector provided with two separate tubular portions of a flat portion; and / or - the conductive core of the electrical cable is made of copper rather than aluminum, and the connection device is devoid of an insert. The method just described comprises a step of deformation of the transition portion until said transition portion forms a substantially straight bottom wall of the tubular portion, wherein said bottom wall extends substantially perpendicular to the longitudinal general direction of the tubular portion. It is recalled more generally that the invention is not limited to the examples described and shown.

Claims (18)

REVENDICATIONS1. A method of manufacturing a connecting device (3) to be crimped on a bare terminal section (6) of electric cable (4), comprising the step of providing a conductive element (7) made in one piece and having a portion tubular (13) extending in a longitudinal general direction, an insertion opening (16) through which it is intended to introduce into said tubular portion (13) said stripped end portion (6) and a flat portion (15). configured to cooperate with a predetermined electrical terminal, said tubular portion (13) being connected at an end opposite said insertion opening (16) by a transition portion (14) to said flat portion (15); said method being characterized in that it further comprises a step of deforming said transition portion (14) until said transition portion (14) forms a substantially straight bottom wall of said tubular portion (13) wherein said bottom wall extends substantially perpendicular to said longitudinal general direction of said tubular portion (13). 2. Method according to claim 1, characterized in that it further comprises the following steps: - providing a conductive cylindrical tube having a predetermined first internal diameter and which comprises said insertion opening (16); at least partially expanding said conductive cylindrical tube to form said tubular portion (13), which is provided with at least one first tubular section (22) having a second internal diameter greater than said first predetermined internal diameter. 3. Method according to claim 2, characterized in that said deformation and expansion steps are performed at the same time by inserting a deformation and expansion pin (25) in said opening opening (16) of said cylindrical tube driver. 4. Method according to one of claims 2 and 3, characterized in that it comprises the step of flattening said cylindrical tube at one end of said cylindrical tube opposite to said insertion opening (16) so as to form 2 Said flat portion (15) and said transition portion (14) connecting said tubular portion (13) to said flat portion (15). 5. Method according to claim 4, characterized in that it comprises the step of deforming said tubular portion (13) so as to form an annular shoulder (17) near said transition portion (14). 6. Method according to any one of claims 1 to 5, characterized in that it comprises the step of drilling said flat portion (15) so as to form an orifice (12) configured to receive a fixing member of said predetermined electrical terminal. 10 7. Method according to any one of claims 1 to 6, characterized in that said connecting device (3) further comprises a sheath (32) configured to be disposed within said tubular portion (13) and in which is intended to introduce said stripped end portion (6), said sleeve (32) having a plurality of perforations (59) and being of a material harder than aluminum so that said sleeve (32) is configured for deforming said stripped end portion (6) with said aluminum conductive core (35) which is configured to be embedded in said perforations (59) of said sleeve (32); said method further comprising the steps of providing said sleeve (32) and introducing it at least partially into said tubular portion (13); whereby said connecting device (3) is suitable for said electrical cable (4) which has a conductive core (35) made of aluminum. 8. Method according to any one of claims 1 to 7, characterized in that it comprises the step of introducing a predetermined amount of contact grease (10) into said tubular portion (13), against said wall of substantially straight bottom. 9. Method according to any one of claims 1 to 8, characterized in that it comprises the steps of providing a plug (8) and mount it on said tubular portion (13) at said opening opening 30 (16). Crimp connection device on a stripped end section (6) of electric cable (4), comprising a conductive element (7) made in one piece and having a tubular portion (13), an introduction opening (16) by which said bare end portion (6) is provided with said tubular portion (13) and a flat portion (15) configured to cooperate with a predetermined electrical terminal, said tubular portion; (13) being connected at an end opposite said insertion opening (16) by a transition portion (14) to said flat portion (15); said device (3) being characterized in that said transition portion (14) is deformed so as to form a substantially straight bottom wall of said tubular portion (13), wherein said bottom wall extends substantially perpendicular to said longitudinal general direction of said tubular portion (13). 11. Device according to claim 10, characterized in that said tubular portion (13) comprises a first tubular section (22) formed by expansion and having a second internal diameter, which first tubular segment (22) has an equal length or greater second internal diameter. 12. Device according to claim 11, characterized in that said tubular portion (13) has an annular shoulder (17) near said substantially straight bottom wall. 20 13. Device according to claim 12, characterized in that said first tubular section (22) is provided between said insertion opening (16) and said shoulder (17), and said tubular portion (13) further comprises a second section tubular (23) between said shoulder (17) and said substantially straight bottom wall, which second tubular section (23) has a first predetermined internal diameter less than said second predetermined internal diameter of said first tubular section (22). 14. Device according to claim 12, characterized in that said second tubular section (23) has a length less than said first internal diameter. 30 15. Device according to any one of claims 10 to 14, characterized in that said flat portion (15) is provided with an orifice (12) configured to receive a fixing member of said predetermined electrical terminal. . 16. Device according to any one of claims 10 to 15, characterized in that it is configured to be crimped on an electric cable (4) 5 provided with a conductive core (35) of aluminum and that it comprises in in addition to a sheath (32) disposed inside said tubular portion (13) and in which it is intended to introduce said stripped end portion (6), said sheath (32) having a plurality of perforations (59) and being in a material harder than aluminum so that said sheath (32) is configured to deform said stripped end section (6) with said aluminum conductive core (35) which is configured to be embedded in said perforations (59); ) of said sheath (32). 17. Device according to any one of claims 10 to 16, characterized in that it further comprises a predetermined amount of contact grease (10) in said tubular portion (13) against said substantially straight bottom wall. 18. Device according to any one of claims 10 to 17, characterized in that it further comprises a plug (8) mounted on said tubular portion (13) at said insertion opening (16).