Electrical terminal with locking lance

Abstract: A tab terminal comprises an inner contact body (4) and an outer spring body (6) having a locking lance (50). The outer body (6) is mounted over the inner body in a vertical direction, whereby inwardly bent tabs (26) of the inner contact body receive a side wall (48) of the outer body, the other side wall (46) of the outer body having a clinching tab (60) that engages in a cutout (40) of the inner contact body. The latter enables a very simple assembly procedure that reduces assembly time, tool complication, and therefore production costs.

Description: This invention relates to an electrical terminal having a contact body, and an additional body with a locking lance mounted thereon. Many electrical terminals are stamped and formed from sheet metal and comprise a connection section for connection to a complementary conductor such as a wire, a body section, and a contact section for mating with a complementary terminal. Certain terminals have resilient locking lances stamped from the body section for engaging with a shoulder of a connector housing cavity in order to retain the terminal in the housing. A locking lance which is stamped directly from the inner contact body may however not be sufficiently strong to support the required retention forces, or require a stronger and more resilient material to be used for the contact body. Resiliency and strength of the sheet metal however usually entails a material that is harder to stamp and form, and which is not well adapted for crimping connection to conducting wires. A compromise is usually sought between the need for good electrical and crimping properties, and the need for a strong and resilient material. A common means of overcoming this problem is by providing an additional outer body that is mounted around the body section of the inner contact body. The outer body may be produced of a material that has the required strength and resiliency for providing locking lances. Such terminals are generally more expensive to manufacture than single piece terminals, not only because of the need to stamp and form an additional part, but also because of the need to assemble the outer body over the inner body. Assembly of these parts is a significant cost driver in the manufacturing of two piece terminal, because the assembly cycle may take more than double the time than the stamping cycle. The assembly procedure also usually requires more complicated tooling which is not only more expensive, but also less reliable. A typical way of mounting an outer body with locking lances, to an inner body, is to wrap the outer body around the inner body, usually by partially stamping the outer body and slipping it axially (in the direction of mating of the terminal) over the body section and then performing a final clinching or closing operation to affix the outer body to the inner body. This is a particularly time consuming and difficult operation. It would therefore be desirable to provide a two part electrical terminal that is very cost-effective to manufacture, and in particular where the assembly procedure is simplified. It is therefore an object of this invention to provide a two part electrical terminal that is cost-effective to manufacture, and in particular to assemble. The objects of this invention have been achieved by providing an electrical terminal with the features of claim 1. The terminal comprises an inner stamped and formed body having a connection section, a body section and a contact section for mating with a complementary terminal, further comprising an outer spring body having a resilient locking lance, the outer body comprising a base wall from which the locking lance is stamped, the base wall mountable against a top end of the inner contact body. Further advantageous features of the invention are described in the description and claims. Embodiments of this invention will now be described, by way of example, with reference to the figures, whereby; Figure 1 is a top view of a terminal according to this invention; Figure 2 is a view in the direction of arrow 2 of Figure 1; Figure 3 is a cross-sectional view through lines 3-3 of Figure 2; Figure 4 is a cross-sectional view through lines 4-4 of Figure 1; Figure 5 is a similar view to that of Figure 4 but with the outer spring body about to be assembled to the inner contact body; Figure 6 is view of a partially stamped layout of the outer body; Figure 7 is a side view of the outer body; Figure 8 is a view in the direction of arrow 8 of Figure 7; Figure 9 is a view in the direction of arrow 9 of Figure 7; Figure 10 is a view of a partially stamped layout of the inner contact body; Figure 11 is a partial cross-sectional side view of the inner contact body; Figure 12 is a partial cross-sectional top view of the inner contact body; Figure 13 is a cross-sectional view through lines 13-13 of Figure 12; Figure 14 is a cross-sectional view through lines 14-14 of Figure 12; Figure 15 is a cross-sectional view through lines 15-15 of Figure 12; Figure 16 is a cross-sectional view through lines 16-16 of Figure 12; Referring to Figures 1-5, an electrical terminal 2 comprises an inner contact body 4 and an outer body 6. The inner body 2 is stamped and formed from sheet metal and comprises a connection section 8 for crimping to a conducting wire, a body section 10 and a pin contact section 12 for mating with a complementary terminal. Referring mainly to Figures 11-15, the body section 10 is substantially U-shaped and comprises a base wall 14 and side walls 16,18 extending upwardly from the base wall whereby one of the side walls 16 extends to a free end 20 that extends beyond the free end 22 of the opposing side wall, with respect to the base wall 14. This additional extension 24 provides on the one hand a means for polarizing the terminal with respect to a connector housing cavity for receiving the terminal, and on the other hand provides protection for a locking lance positioned on the outer body by preventing entanglement thereof with foreign objects such as wires. The side wall 16 further comprises a pair of inwardly stamped tabs 26 that have a wall portion 27 extending parallel to the side walls 16 to a top end 29 and spaced from the side wall by a gap G that is adapted to receive a wall of the outer body therein as will be explained hereinbelow. The opposing side wall 18 has a top wall portion 30 extending progressively from a position proximate the connection section 8 towards the contact section 12, over the base wall 14 to provide a top wall 30 for extending into the contact section 12. The contact section 12 is substantially U-shaped having the top wall 32 extending through a U-bend 34, to a bottom wall 36 that extends from the base wall 14 of the body section. The contact section top and bottom walls 32,36 provide contact surfaces 37,38 that are on the plated surface of the sheet metal, rather than on the sheared edges, for electrical contact with complementary receptacle contacts thereagainst. The latter ensures good electrical contact, for situations where the mating contact has a specific orientation with respect to the terminal 2. The base wall 14 is provided with a cutout 40 that extends into the side wall 18 and is for clinching of the outer body to the inner body. Referring to Figures 6-9 and Figures 3-5, the outer body 6 comprises a top wall 44, a side wall 46 extending therefrom and a second side wall 48 parallel and opposed thereto also extending from the top wall. The outer body 6 is stamped and formed from a resilient sheet metal, such as stainless steel, which has the requisite strength and resiliency for providing a locking lance. A locking lance 50 is formed out of the top wall 44 and extends obliquely outwardly from an attachment portion 52 to a free end 54. The second side wall 48 comprises two spaced apart wall portions 56,58 that are for insertion into the gaps G of the corresponding tabs 26 of the inner contact body (see Figure 13). The first wall 46 is mountable against an outer surface of the inner contact body wall 18, and comprises a clinching tab 60 extending below the wall for deformation into the inner contact body cutout 40. In order to assemble the outer body to the inner contact body, the pre-stamped and formed outer contact body is inserted from above, as shown in Figure 5, over the top 30 of the inner contact body such that the wall portions 56,58 of the outer body are inserted into the gap G of the inner contact body tabs 26 until the top wall 52 abuts the free ends 22 and 29 of the inner contact body side wall 18 and tab 26 respectively (see Figure 13). A forming tool can then be elevated from below the inner contact body base wall 14 to bend the outer contact body clinching tab 30 into the cutout 40. The latter assembly procedure is advantageous in that the assembly movement of the outer body is unidirectional and vertically above the inner body such that the strips of sheet metal of the inner and outer bodies by overlap in the assembly tool. As with the mounting of the outer body to the inner body in the vertical direction, clinching of the tab 60 can also be effected by vertical movement which enables provision of a more simple forming tool. Not only is the assembly procedure very simple, but the outer body requires less material than an outer body which is wrapped around the whole inner body. The inner contact body also makes effective use of material, as can be seen in the layout of Figure 10, by restricting the width of the contact layout to that necessary for the wire crimping barrel arms 64. Also advantageous is the gradual bending over of the top wall 30 from the side wall 18 to extend into the contact section 12 which has a U-profile presenting plated contact surfaces 37,38 for mating against a complementary terminal. Advantageously therefore, assembly of the outer body to the inner contact body is effected with particularly simple operations, and the design of both the outer body and the inner contact body require little material usage, whilst nevertheless providing a reliable contact. Advantageously therefore, rapid assembly of the outer body to the inner body is enabled by simply inserting and latching the outer body in a gap provided between top walls of an inner contact body. Manufacturing costs are thereby reduced.

Claims: An electrical terminal (2) stamped and formed from sheet metal and comprising an outer body (6) with a locking lance (50), and an inner contact body (4) having a connection section for connection to a conducting wire, a body section (10), and a contact section (12) extending therefrom for connection to a complementary terminal, the body section (10) comprising a base wall (14) and side walls (16,18) extending upwardly therefrom to a top end (30), the outer body comprising a top wall (44) mountable against the inner body top end (30) and a side wall (48) mountable against an inner body side wall (16), characterized in that the outer body side wall (48) engages vertically in a gap (G) that is formed by tabs (26) extending alongside the inner body side wall such that the outer body is mountable to the inner body by movement in the vertical direction, which is orthogonal to the mating direction of the terminal. The terminal of claim 1 wherein the outer body comprises a second side wall (16) mountable adjacent the opposing side wall (18) of the inner body, the terminal comprising interengaging fixing members (40,60) between the second side wall (16) and inner body for permanent attachment therebetween. The terminal of claim 1 or 2 wherein the inner body side wall tabs (26) are stamped out of the side wall (16). The terminal of claim 2 wherein the interengaging fixing members comprise a clinching tab extending from a lower end of the outer body second side wall, that is clinched through a cutout (40) in the inner body, to the corresponding inner body side wall (18).

Inventors: BOEMMEL CHRISTIAN OTTO, GAULTON PETER DONALD, JETTER ROLF, KUIPER-MOORE DAVID BOUWE, LEHNER ANTONIO, BOEMMEL, CHRISTIAN OTTO, GAULTON, PETER DONALD, JETTER, ROLF, KUIPER-MOORE, DAVID BOUWE, LEHNER, ANTONIO
Applicants: WHITAKER CORP, THE WHITAKER CORPORATION
Application year: 1996
Main classification: H01R13
IPC codes: H01R43, H01R13