WO2014127819A1

WO2014127819A1 - Electrical female terminal

Info

Publication number: WO2014127819A1
Application number: PCT/EP2013/053416
Authority: WO
Inventors: François CORMIER; Ould M.L. YAHYA; Nicolas Hermeline
Original assignee: Delphi International Operations Luxembourg S.À.R.L.
Priority date: 2013-02-21
Filing date: 2013-02-21
Publication date: 2014-08-28

Abstract

Electrical female terminal (100) for automotive vehicle connectors. The female terminal (100) comprises a box-shaped cage (130) extending in a terminal insertion direction between a front opening and tail. A tooth (160) made of a double layer of sheet metal in inserted in a cutout (147) for closing the cage (130).

Description

Electrical female terminal FIELD OF THE INVENTION

The invention relates to electrical terminals, and more particularly to electrical female terminals to be accommodated in connectors used for automotive vehicles. BACKGROUND OF THE INVENTION

For electrical connections in automotive vehicles, it is common to use male and female terminals made of metal such as copper, mounted in connector housings made of insulating material, such as plastics.

These terminals are usually made of a folded and stamped sheet metal. In this document sheet metal means sheet of metal and such a sheet metal is not necessarily made of steel or any other iron alloy. It can be a copper alloy for instance.

Female terminals comprise

a rear tail for attaching (e.g. by crimping and/or soldering) an electrical lead and

a cage for receiving a male terminal pin.

The cage has a box shape with a top wall, a bottom wall and two lateral walls. These walls extend substantially in the direction of insertion of the male terminal pin in the cage. In other words, the cage has a longitudinal direction corresponding to the insertion direction of the male terminal pin within it. Such a pin is inserted through the front opening of the cage. The rear tail is at the opposite longitudinal side of the cage, relatively to the front opening.

For at least partially contributing to the closing of the cage and preventing its opening when a pin is inserted in the cage, it is known to cut out a tooth which extends from one wall and to insert it in a cutout or opening of another wall, for at least partially contributing to the closing of the cage. The closing of the cage can also be provided by other teeth of other means. The patent document EP2193577B1 for instance discloses such a prior art configuration.

It is a common trend to miniaturized connectors and terminals. The more miniaturized the terminal is, the more difficult it is to make it robust. If the cage lacks robustness, it may open and the quality of the electrical contact between the male and female terminals can be damaged.

An aim of the invention consists in improving the manufacturing of miniaturized female terminals, and more particularly in increasing the robustness of such terminals.

This aim is at least partially achieved with a female terminal for automotive vehicle connectors, wherein the tooth comprises at least a double layer (i.e. resulting in a double thickness) of sheet metal. For instance the tooth extends from an edge of the top wall and is anchored in a cutout made in a lateral wall adjacent to this edge. This way the cage is closed.

The thickness of the tooth which is inserted in the adjacent wall cutout is increased. For instance, the increased thickness corresponds to twice the thickness of the sheet metal in which the terminal is stamped. When the female terminal according to the invention is made of a single sheet metal, the double thickness of the tooth can be obtained for instance with a 180-degree-fold of the sheet metal forming the top wall.

Several factors may contribute to obtain a stronger cage. For instance the increased quantity of material which serves to latch the tooth in its opening enhanced its robustness. A spring back effect can also be obtained which tends to space apart the layers of sheet metal forming the tooth, so as to increase the tooth retention in the cutout.

In terms of manufacturing, the process according to the invention comprises steps of stamping and folding a sheet metal for making a cage, in which a male terminal pin will be inserted, and a rear tail, for attaching a cable. At least one folding step is carried out for making a box-shaped cage with a top wall, a bottom wall and two lateral walls. At least one stamping step is carried out for cutting out a tooth extending from a wall and a for cutting out a cutout in another wall. It also comprises folding the sheet metal for having a tooth with a double thickness and inserting the tooth within the cutout. BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the invention appear from the following detailed description of embodiments, given by way of non-limiting examples, and with reference to the accompanying drawings.

In the drawings:

- Figure 1 represents schematically in perspective an embodiment of a terminal according to the invention;

- Figures 2a to 2d are schematic perspective views of successive steps of the manufacturing process of the terminal of Fig. 1;

- Figure 3 and 4 represent schematically partial cross-sections of the terminal of figure 1, respectively according to a transverse cross section IV-IV and according to a longitudinal cross section III-III; and

- Figure 5 represents a similar cross section as the one of Figure 3 of another embodiment of the terminal according to the invention.

MORE DETAILED DESCRIPTION OF THE INVENTION

On the figures, the same references denote identical or similar elements.

Figure 1 shows an electrical female terminal 100. Such a terminal is intended to be accommodated in an electrical connector housing made of insulating material such as plastics (e.g. PBT, PA66, etc.).

The terminal 100 has a rear tail 120. On the figures the rear tail is only partially represented as its structure does not relate directly to the invention. The rear tail 120 has a crimping section for attaching an electrical lead. The terminal 100 also comprises a cage 130 for receiving a male terminal pin 200 (only the tip of this male terminal is represented on Fig. 1).

The cage 130 extends in the insertion direction D defined by the direction of mating or insertion of the male terminal pin 200 in the cage 130. Consequently, the cage 130 extends between a front end, here a front opening 132, through which the male terminal pin 200 is inserted, and the rear tail 120. The cage 130 is adapted for receiving male pins having a cross-section having a nominal width of about 0.5mm and a nominal thickness of about 0.4mm. For example, the external dimensions of the cage are 1mm width (from a lateral wall to the other) and 1.15mm height (from the top wall to the bottom wall). If the sheet metal is 0.15mm thick, the internal dimensions are about 0.7mm width and 0.85mm height. These are average values as the female terminals are manufactured within specified tolerance ranges.

The cage 130 has a box shape with a top wall 134, a bottom wall 136 and two lateral walls 138, 140 extending substantially in the insertion direction D of the male terminal pin 200 in the cage 130.

The top and bottom walls 134, 136 face each other and are essentially parallel to each other. The lateral walls 138, 140 also face each other and are essentially parallel to each other. The top and bottom walls 134, 136 are essentially perpendicular to the lateral walls 138, 140. The top wall 134 comprises at least a front portion having two thicknesses of sheet metal.

One of the lateral walls is continued above and bent over the top wall 134 for forming a reinforcement rib 142 extending longitudinally over at least a part of the cage 130. A locking lance 144 is cut out and bent upwardly so as to protrude from the rib 142. The locking lance 144 is intended to engage the connector housing for locking the terminal 100 in a housing cavity.

The rib 142 comprises two U-shaped portions or gutter- shaped portions 146, 148, respectively in front of the locking lance 144 (relatively to the insertion direction D) and rear the locking lance 144.

The manufacturing of the female terminal 100 and the forming and closing of its cage 130 are explained with the help of figures 2a to 2d.

As shown on Fig. 2a, the female terminal 100 is made of a single piece or sheet 500 (blank) of an electrically conducting metal such as copper. At previous stages which are not shown, the sheet metal is stamped for making several cutouts. In particular, a tongue 143 defined by an L-shape cutout 145 is designed to form the locking lance 144.

Another cutout 147 is made in the portion of the sheet metal linking the tongue to the remaining part of the sheet metal 500.

Two contact spring beams 150, 152 are also cut out so as to remain linked to the sheet metal 500 by a support portion 154. The support portion 154 of two contact beams 150, 152 forms a portion of the top wall 134 a tooth 160 will extend from. The support portion 154 of the contact beams 150, 152 comprises a window 156 which is cut out, in the support portion 154, substantially in front of the contact spring beam 150. A latch tooth 162 extends from the rib 142.

The cage 130 will comprise, once the manufacturing process completed, two contact spring beams 150, 152 extending from the support portion 154 to free ends. The two spring beam 150, 152 are linked together by a joint 153. One of these spring beams 150, 152 has a contact portion 158 designed to contact the male terminal pin 200 when inserted in the cage 130.

As shown at figure 2b, the sheet metal 500 is folded so as to cover one 152 of the contact spring beams with the other one 150. In other words, the spring beams 150, 152 are folded one over the other with a 180-degree bending of the joint 153. This way, a 180-degree-folded tooth 160 is formed. The contact spring beams 150, 152 are also bent so that they will protrude or bulge in the cage 130 once the manufacturing of the terminal 100 is completed.

The sheet metal is folded substantially parallel to the insertion direction D along a first fold 162 and a second fold 163 (see figure 2c), for forming the rib 142. The cross-section of the rib 65 at this stage has a substantially U- shape. The front 146 and rear 148 U-shaped portions are folded at these folding steps. The front U-shaped portion 146 of the rib 142 comprises a latch tooth 162. At this stage, the locking lance 144 is also bent for making it protruding from the remaining part of the terminal 100 (i.e. essentially the cage 130 and the rib 142).

At the stage illustrated by Fig. 2d, the forming of the cage 130 and the rib 142 is almost complete. The window 156 opens on the top surface of the support portion 154, comprised on what will become the top wall 134. The 180-degree- folded tooth 160 and a rear tooth 164 appear on the edge of the top wall 134 of the cage 130.

Once the manufacturing process completed, as shown on figure 3, the rib 142 lies on the top wall 134 of the cage 130. The rib 142 extends longitudinally over at least a part of the support portion 154. The 180-degree-folded tooth 160 and the rear tooth 164 are inserted in respective cutouts (See also Fig. 1). More particularly, Fig. 3 shows the way a 180-degree-folded tooth 160 engages the cutout 147 made in a lateral wall of the cage 130. More precisely, the tooth 160 extends from an edge 135 of the top wall 134 and is anchored in 147 cutout made in a lateral wall 138 adjacent to this edge 135. It can be also seen on Fig.3 that a side wall 139 of the rib 142 extends from the lateral wall 138 of the cage within which is made the cutout 147 receiving the double-thickness tooth 160, and that another side 141 of the rib 142 has an edge 143 from which extends the latch tooth 162.

On the cross-section of Fig. 4, it is shown how the latch tooth 162 is inserted and engages the window 156.

With these two anchoring means 147, 156, 160, 162, the cage 130 is securely closed and both the rib 142 and the locking lance 144 are strongly maintained on the cage 130.

Various embodiments of the terminal according to the invention can be easily derived. For instance, the thickness of the tooth 160 is not limited to two layers. It could be formed with three or more layers stacked one over the others and not necessarily all linked by a folded joint.

For example figure 5 represents another embodiment of the female terminal according to the invention which differs from the one of Fig. 1 to 4, mainly by the fact that the top wall 134 is folded differently. Indeed, the 180- degree-folded tooth 160 is folded so as to have the same surface of the sheet metal 500 which covers the internal faces of the cage 130. More precisely, the respective contact portions of the internal spring beam 150' and of the bottom wall 136 face each other and can be covered by a same layer of precious metal (such as gold). This makes the contact coating step of the manufacturing process less expensive less expensive than when both surfaces of the sheet metal have to be coated.

Claims

1. Female terminal for automotive vehicle connectors, made of a folded and stamped sheet metal (500), comprising a cage (130), for inserting a male terminal pin (200), a rear tail (120), for attaching a cable, the cage (130) having a box shape with a top wall (134), a bottom wall (136) and two lateral walls (138, 140) extending substantially in a direction (D) of insertion of the male terminal pin (200) in the cage (130), between an opening (132) and the rear tail (120), the female terminal (100) further comprises a tooth (160) extending from one wall (134) and inserted in a cutout (147) of another wall (138) for at least partially contributing to the closing of the cage (130),

characterized in that the tooth (160) comprises at least a double layer of sheet metal.

2. Terminal according to claim 1, wherein the tooth (160) extends from an edge (135) of the top wall (134) and is anchored in a cutout (147) made in a lateral wall (138) adjacent to this edge (135).

3. Terminal according to claim 1 or 2, wherein of the double layer of the tooth (160) is obtained with a 180-degree-fold of the sheet metal forming the top wall (134).

4. Terminal according to any preceding claim, comprising two contact beams (150, 152) the support portion (154) of which forms a portion of the top wall (134) the tooth ( 160) extends from.

5. Terminal according to claim 4, wherein the support portion (154) of the contact beams (150, 152) comprises a window (156) within which is inserted a latch tooth (162) extending from a rib (142) extending longitudinally over at least a part of the cage (130).

6. Terminal according to claim 5, wherein a side wall of the rib (142) extends from the lateral wall (138) of the cage within which is made the cutout (147) receiving the double-thickness tooth (160), and wherein another side of the rib has an edge from which extends the latch tooth (162).

7. Terminal according to any preceding claim, wherein the same surface of the sheet metal (500) covers the internal faces of the cage (130).

8. Manufacturing process for making electrical terminals,

comprising at least one folding step of a sheet metal (500) for forming a box-shaped cage with a top wall (134), a bottom wall (136) and two lateral walls (138, 140), the cage (130) being designed to receive a male terminal pin (200), in a direction of insertion (D), through a front opening (132), and

comprising at least one stamping step for cutting out a tooth (160) extending from one wall (134) and a cutout (147) in another wall (138),

characterized in it further comprises a step of folding the sheet metal for having a tooth (160) with a double thickness and inserting the tooth (160) within the cutout (147).

9. Manufacturing process according to claim 8, wherein the double thickness of the tooth (160) is obtained with a 180-degree folding of the sheet metal.

10. Manufacturing process according to claim 8 or 9, wherein the tooth (160) is made of a 180-degree folded joint (153).

11. Manufacturing process according to claim 10, wherein the joint (153) links two spring beams (150, 152).