EP1057228A1

EP1057228A1 - Electrical connector contact pin

Info

Publication number: EP1057228A1
Application number: EP99904934A
Authority: EP
Inventors: Jean-Bernard Paul Despouys
Original assignee: Radiall SA
Current assignee: Radiall SA
Priority date: 1998-02-24
Filing date: 1999-02-23
Publication date: 2000-12-06
Anticipated expiration: 2019-02-23
Also published as: FR2775389B1; FR2775389A1; WO1999044261A1; US6475039B1; EP1057228B1

Abstract

The invention concerns an electrical connector, comprising a body (2), a connecting element (3) and a sleeve (4), the connecting element being maintained in the extension of the body by being coupled with a locking pin (8) projecting from the body front face, the sleeve being arranged around the connecting element and maintained on the body by clamping an annular portion (6) of the latter. The connecting element (3) comprises, on the locking pin side, an end to be coupled with the locking pin, shaped such that the locking pin cannot be inscribed inside said coupling end transverse cross-section, the connecting element (3) being capable of elastic deformation to enable its coupling end to be fitted on the locking pin (8), said connecting element thus deformed being not capable of being inscribed inside the sleeve (4) transverse cross-section.

Description

Contact pin of an electrical connector

The present invention relates to a contact pin of an electrical connector.

Multi-pin electrical connectors generally have a large number of contact pins which include a connection end intended to cooperate with the connection end of a contact pin of an associated multi-pin connector and a connection end intended to receive a conductor of electric cable welded, soldered or wound on said end.

It is known to produce these contact pins in two parts, namely a front part constituting the connection end and a rear part constituting the connection end, so as to be able to use different materials whose elasticity properties and of plasticity are adapted.

In such contact pins, a problem arises for the connection of the front and rear parts, knowing that this connection must be carried out in a simple and rapid manner and must provide a good electrical contact by introducing the minimum of disturbances into the electrical signal. transmitted by the spindle.

The present invention aims to provide a new contact pin made in two parts which constitutes an original solution to the above problem.

The subject of the present invention is a contact pin of an electrical connector comprising a body, a connection element and a sleeve, the connection element being held in the extension of the body by coupling with a pin projecting from the front face. of the body, the sleeve being arranged around the connection element and held on the body by tightening an annular portion of the latter, said contact pin being characterized in that the connection element comprises, on the side of the pin, one coupling end with the pin, shaped in such a way that the pin cannot fit inside the cross section of said coupling end, the connection element being able to deform elastically to allow its coupling end to be fitted onto the pin, said connection element thus deformed being unable to fit inside the cross section of the sleeve, and by the fact that the sleeve and the pin are separated by a clearance greater than the thickness of the wall of the coupling end of the connection element.

In other words, in the contact pin according to the invention, the element of connection is trapped between the pin integral with the body and the sleeve under conditions such that said connection element is elastically constrained by the pin and by the sleeve.

The sleeve being moreover firmly secured to the body by a force fitting on an annular portion of the body, it follows that the mechanical connection between the connection element and the rest of the contact pin is particularly reliable.

It is understood that, because the connection element has undergone, during its establishment between the pin and the sleeve, only elastic deformations, the forces which are exerted, on the one hand, between the connection element and the sleeve and on the other hand, between the connection element and the pin are due to the elastic return of the connection element.

In other words, the connection element does not undergo any plastic deformation which would reduce the forces which it exerts by elastic return on the sleeve and on the pin. Another essential advantage of the contact pin according to the invention is to allow relatively wide manufacturing tolerances, since the elasticity of the connection element makes it possible to make up for to a large extent the design defects between parts.

Thus, taking into account the manufacturing tolerances of the body of the connection element and of the sleeve, the contact pin, according to a preferred embodiment of the invention, can be defined as satisfying the following conditions:

DText. max <Ds _m j _n

Dsmin "Dp _ma χ> 2.e _max

Dτint.max <Dp _m i _n ⁾ p _m i _n . Djjn .max> D§ _m ax "Dτext.min where

"Dτ _ex t.max ^is I ^th maximum outside diameter of the connection element, taking into account its manufacturing tolerances,

"Dτext.min I ^e ^is minimum outside diameter of the connecting element, taking into account production tolerances, ~ I ^e Dτint.max ^is maximum internal diameter of the connecting element, given manufacturing tolerances,

- e _max is the maximum thickness of the connection element, taking into account its manufacturing tolerances, - Ds _m in is the minimum internal diameter of the sleeve, taking into account its manufacturing tolerances,

- Ds _m a is the maximum internal diameter of the sleeve, taking into account its manufacturing tolerances,

- Dp _max is the maximum outside diameter of the pin, taking into account its manufacturing tolerances,

- Dp _m i _n is the minimum outside diameter of the pin, taking into account its manufacturing tolerances.

It goes without saying that the possibility of automatically compensating for manufacturing tolerances, by virtue of the arrangement of the contact pin according to the invention, makes it possible to manufacture the various parts which constitute it by implementing simple and inexpensive manufacturing methods. expensive, while retaining good electrical qualities on the spit.

In a particular embodiment of the invention, the connection element is dimensioned so that it can slide freely in the sleeve before having undergone the deformation resulting from the fitting of its coupling end on the pin.

In a preferred embodiment, the connection element has a longitudinal slot which allows it to pass from a closed position in which the two edges of said slot touch to an open position in which the two edges of said slot are spaced one from the other, this open position resulting from the deformation of said connection element.

Preferably, the connection element is in its closed position before having undergone the deformation resulting from the fitting of its coupling end on the pin.

Thus, after fitting the sleeve, the connection element returns to a position close to its closed position, the two edges of its slot being almost contiguous, this which has the consequence that the connection element, once in place in the contact pin, can keep a stable shape, even after a significant number of connections / disconnections, due to the fact that only its interface part proper is deformed elastically. In general, as is the case with most of the known contact pins, the body, the connection element and the sleeve of the pin according to the invention are substantially revolution parts.

In a particular embodiment, the coupling end of the connection element has a circular cross section with an internal diameter less than the internal diameter of the circular cross section of the rest of the connection element.

The present invention also relates to a method of mounting a contact pin as described above.

Such a method is characterized in that it consists in fitting the coupling end of the connection element onto the pin of the body of the pin, then in presenting the sleeve in alignment with the connection element deformed, the sleeve being held in a sleeve whose internal dimensions correspond substantially to the external dimensions of the sleeve, to engage the sleeve held in the sleeve around the connection element in an axial translational movement until the sleeve has completely covered with the connection element, then moving the sleeve in the sheath while keeping the latter stationary to bring said sleeve by axial translation on the annular portion of the body, before removing the sheath.

This method has the essential advantage that it only comprises axial translation operations, which facilitates its automation.

In order to better understand the invention, we will now describe an embodiment given by way of non-limiting example with reference to the accompanying drawing in which:

FIG. 1 is a view in longitudinal section of a contact pin according to the invention,

FIG. 2 is a close-up view in longitudinal section of the connection element of the pin of FIG. 1, FIG. 3 is a left view of FIG. 2,

FIG. 4 is a top view of FIG. 2,

- Figures 5 and 6 are perspective views of the connection element of Figure 2, - Figures 7A, 7B, 7C and 7 D are views in partial section of the contact pin during its assembly, and

- Figures 8A, 8B and 8C are sectional views along VIII-VIII of Figures 7A, 7B and 7C.

The contact pin 1 shown in FIG. 1 comprises a body 2, a connection element 3 and a sleeve 4.

The body is extended to the left by a connection end (not shown) which can have different shapes for connection to a cable conductor. It can be a crimp barrel, a wrapper (or winding) outlet for the conductor, or a spike outlet for a printed circuit board. Opposite its connection end, the body 2 comprises a flange 5 of large diameter which borders an annular portion 6 of smaller diameter provided for retaining the sleeve 4.

Projecting from the front face 7 of the body, which delimits the annular portion (6) with the flange 5, a pin 8 of circular section and of diameter Dp smaller than that of the annular portion 6 is provided for receiving the connection element . The body 2 is made of brass which is an inexpensive material. The connection element 3, which is better visible in FIGS. 2 to 6, is substantially in the form of a tube comprising a longitudinal slot 9.

In its closed position shown in FIGS. 2 to 6, 7A and 8A, that is to say in its position in which the two edges 10 of its longitudinal slot 9 touch, the connection element 3 has an outside diameter Dy _ex t, slightly smaller than the inside diameter D _s of the sleeve, so that the connection element can, in its closed position, slide freely in the sleeve.

At its front end, that is to say to the right with respect to the figures, the connection element 3 comprises four slots 11 which separate four elastic fingers 12 folded down in the direction of the axis of the connection element, intended to constitute a female connection interface with a corresponding male contact pin (not shown). Opposite this connection interface, the connection element 3 has a coupling end 13 with the pin 8 of the body.

The shape of this coupling end 13 is better visible in FIGS. 2 to 4 where it can be seen that a cutout 14, produced in the wall of the connection element, leaves a portion of the rear face 15 ring whose two ends 16 are deformed towards the inside of the connection element.

The wall of the connection element has the same thickness over its entire length, including at its coupling end 13.

As can be seen in FIGS. 3 and 8A, the coupling end thus formed internally leaves, in the closed position of the connection element, only room for a cylindrical volume which is materialized by a circle represented in broken lines , which is inscribed inside the cross section of the coupling end.

This circle has a diameter Dχj _nt smaller than that Dp of the pin 8 projecting from the front face of the body.

Consequently, this pin 8 cannot register inside the cross section of the coupling end when the connection element is in the closed position.

We will now describe the mounting of the spindle according to the invention with reference to Figures 7A to 7D and 8A to 8C.

As can be seen in FIGS. 7B and 8B, the fitting on the pin 8 of the coupling end 13 of the connection element 3 causes the latter to deform, which then takes an open position in which the two facing edges

10 of its slot 9 are distant from each other. In this open position, the connection element 3 undergoes an increase in its outside diameter, by a value equal to the difference D _p - Dχj _nt between the diameter of the pin 8 and that of the circle inscribed inside the section transverse of the coupling end 13.

In other words, after fitting the coupling end 13 on the pin 8, the outside diameter of the coupling element is equal to Dj _ex t + Dp-Dχi _nt

The dimensions of the pin, the coupling element and the sleeve are chosen so that the diameter of the connection element deformed by fitting on the pin is greater than the inside diameter D _s of the sleeve.

Therefore, if one presents the sleeve 4 in alignment with the connection element 3 and that it slides axially around this connection element 3 using a sheath 17 which holds it firmly in particular by preventing it from deforming radially, the connection element is tightened to a position close to its closed position in which the facing edges 10 of its longitudinal slot 9 are very close to one of the other, as seen in Figures 7C and 8C.

In this position, the radial clearance D _s - D _p existing between the pin and the inner wall of the sleeve is occupied by the coupling end of the connection element, elastically stressed between said sleeve and said pin.

In order to avoid any creep of the pin, of the connection element or of the sleeve, so that the engagement of the sleeve around the connection element only results in a purely elastic deformation of the element connection, the dimensions of the various components of the contact pin were determined so that the radial clearance (D _s -D _p ) / 2 existing between the pin and the inner wall of the sleeve is greater than the thickness e of the wall of the connection element.

Thus, the connection element undergoes only elastic deformations and exerts by elastic reaction a radial pressure on the pin and on the sleeve. Once the connection element is completely covered by the sleeve, the progression of the sheath 17 is stopped and the sleeve 4 is continued to move axially by pushing it in the direction of the body 2 using a pusher 18, this which causes the radial expansion of the sleeve which engages by force on the annular portion 6 of the body, until it comes into abutment against the flange 5. The sleeve is thus firmly secured to the body.

The connection element, which has undergone only elastic deformations, is also firmly secured to the rest of the contact pin, on the one hand due to its elastic contact with the sleeve, on the other hand, due to of its elastic contact with the pin. It is understood that the elasticity of the connection element can easily be used to compensate for the manufacturing tolerances of the body, the pin of which has a diameter between Dp _m j _n and Dp _max of the sleeve, the inside diameter of which can vary from D _sm i _n to D _smax and of the connection element, the outside diameter of which can range from Dχ _{ext m} i _n to Dχ _{ex max} , and the coupling end of which can leave room for a cylindrical volume with a diameter between Dχj _nt . _m j _n and Dχj _{nt max} .

It is understood that the embodiment which has just been described has no limiting character and that it can receive any desirable modifications without departing from the scope of the invention.

Claims

1. Contact pin of an electrical connector, comprising a body (2), a connection element (3) and a sleeve (4), the connection element being held in the extension of the body by coupling with a pin ( 8) projecting from the front face of the body, the sleeve being arranged around the connection element and held on the body by tightening an annular portion (6) of the latter, characterized in that the element connection (3) comprises, on the side of the pin, an end (13) for coupling with the pin, shaped so that the pin (8) cannot fit inside the cross section of said end coupling element, the connection element (3) being able to deform elastically to allow its coupling end (13) to be fitted onto the pin (8), said connection element thus deformed being unable to s '' inscribe inside the cross section of the sleeve (4), and by the fa it that the sleeve (4) and the pin (8) are separated by a clearance (D _s -D _p ) / 2 greater than the thickness (e) of the wall of the coupling end of the element connection (3).

2. Contact pin according to claim 1, characterized in that before deformation, the connection element (3) can slide freely in the sleeve (4).

3. Contact pin according to any one of claims 1 and 2, characterized in that the connection element (3) has a longitudinal slot (9) which allows it to pass from a closed position in which the two edges (10) of said slot touch at an open position in which the two edges (10) of said slot are spaced from each other, this open position resulting from the deformation of said connection element.

4. Contact pin according to claim 3, characterized in that before deformation, the connection element (3) is in its closed position.

5. Contact pin according to any one of claims 1 to 4, characterized in that the body (2), the connection element (3) and the sleeve (4) are substantially of revolution.

6. Contact pin according to claim 5, characterized in that the coupling end (13) has a circular cross section of internal diameter (Dχj _nt ) less than the internal diameter of the circular cross section of the rest of the connection element. 10 WO 99/44261 PCT / FR99 / 00401

7. Contact pin according to any one of claims 1 to 6, characterized in that the body (2), the connection element (3) and the sleeve (4) satisfy the following conditions:

DText. max <Ds _m in

Dsmin "Dp _m aχ> 2.e _m ax

χint.max <Dp _m j _n

Dpmin - Dχi _n t.max> Ds _max - Dχ _{eXf m} j _n where

"I ^e ^is Dχeχt.maχ maximum outer diameter of the connecting element, taking into account production tolerances,

- Dχ _ex rev./min I ^e ^is minimum outside diameter of the connecting element, because of manufacturing tolerances,

- Dχj _n .m _a χ is the maximum internal diameter of the connection element, taking into account its manufacturing tolerances, - e _max is the maximum thickness of the connection element, taking into account its manufacturing tolerances,

- Dsrnin I ^e ^is minimum inner diameter of the sleeve taking into account production tolerances,

- Ds _max is the maximum inside diameter of the sleeve, taking into account its manufacturing tolerances,

- Dp _m j _n is the minimum outside diameter of the pin, taking into account its manufacturing tolerances.

8. A method of mounting a contact pin according to any one of claims 1 to 7, characterized in that it consists in fitting the coupling end (13) of the connection element (3) on the pin (8) of the body (2) of the spindle, then to present the sleeve (4) in alignment with the deformed connection element (3), 1 1 WO 99/44261 PCT / FR99 / 00401

the sleeve (4) being held in a sleeve (17) whose internal dimensions correspond substantially to the external dimensions of the sleeve, to engage the sleeve (4) held in the sleeve (17) around the following connection element (3) an axial translational movement until the sleeve (4) has completely covered the connection element (3), then to move the sleeve (4) in the sleeve (17) while keeping the latter stationary to bring said sleeve (4) by axial translation on the annular portion (6) of the body (2), before removing the sheath (17).