GB2262664A

GB2262664A - Connector with terminal position assurance member

Info

Publication number: GB2262664A
Application number: GB9224248A
Authority: GB
Inventors: Francois Jodon; Jacques Lalange
Original assignee: Whitaker LLC
Current assignee: Whitaker LLC
Priority date: 1991-11-22
Filing date: 1992-11-19
Publication date: 1993-06-23
Anticipated expiration: 2012-11-19
Also published as: GB9224248D0; FR2684242A1; FR2684242B1; GB2262664B

Abstract

A connector in which terminals are retained in cavities by latches (32) and by flexible arms (26) engaging the terminals, includes a Terminal Position Assurance member (12, 52) which fits between each latch (32) and the adjacent wall of the connector and which spreads flexible arms (26) into engagement with respective opposed terminals. The TPA member (52) is a two-stage device which cannot be fitted unless the latches (32) are properly engaged with the terminals. <IMAGE>

Description

ELECTRICAL CONNECTOR ASSEMBLY WITH TERMINAL LOCKING MEMBER This invention relates to an electrical connector comprising an insulating housing having a plurality of adjacent cavities each for receiving an electrical terminal with a recess therein, a portion of the wall of each cavity being formed with a terminal stop projecting into the cavity, and the wall portions being proximate to, and opposite to, each other.

In the automotive industry there is a requirement for such electrical connectors, from the cavities of which the terminals cannot back out under the action of vibration when the connector is in use, but into the cavities of which the terminals can easily be loaded, the terminals also being readily exchangeable when they have been loaded.

In a related development, which development is more fully described in German Patent Application, Serial Number 3720751.2, there is described a pin and socket type circular connector comprising an insulating housing defining a pair of adjacent cavities, each for receiving an electrical terminal characterized by having a shoulder thereon. A portion of the wall of each cavity is formed with a terminal stop projecting into the cavity. The connector is further characterized by each wall portion being resiliently flexible towards the other wall portion by the abutment of an electrical terminal which has been partially inserted into the corresponding cavity against the stop in the cavity.As a result, the terminal may be further inserted into the cavity beyond the stop, whereafter the wall portion resiles so that the stop engages behind the terminal shoulder to restrain withdrawal of the terminal from the cavity. Thus, when each terminal has been further inserted into its cavity the wall portions are spaced from each other for the reception between them of a terminal locking member to prevent subsequent movement of the wall portions towards one another.

EP Patent 0 306 635 discloses an electrical connector having a housing assembly with plural terminal receiving cavities, and flexible wall portions which prevent mating with a locking member, when terminals inserted into said cavities are not fully seated. Additionally, the locking member is provided with a central arm which engages with the cavity walls in the fully mated condition.

According to a preferred embodiment of this invention, there is provided an electrical connector which is more effective than those described above. For example, by the use of a secondary locking member in the connector of this invention, there is a high retention of the electrical tabs. Further, if the primary terminal locking is damaged, the secondary locking member may provide sufficient retention to the electrical tab. Also, by this arrangement, if a tab is not properly and fully seated within the connector, the secondary locking member cannot be activated or inserted into the connector housing. Thus, both a physical and visual means is provided whereby one can determine whether the connector is properly loaded.

This all is achieved in an electrical connector assembly comprising an insulative housing member having a front face at one end and a mating face at the opposite end. The housing is provided with plural pairs of through cavities to receive electrical terminals within the assembly, and which extend from the front face towards the mating face.

An electrical terminal locking member is provided for insertion into the cavities from the mating face to secure the electrical terminals in a fixed position within said cavities. The assembly is characterized in that each said cavity is provided with a cantilevered terminal locking lance formed integrally with the outer cavity wall and extending longitudinally toward said mating face.Further, each pair of cavities, along a common inner wall, are provided with two flexible spaced apart wall extensions, and that the locking member is provided with a first set of locking arms, one for each said cavity, where one of the locking arms is adapted to seat between each locking lance and the adjacent wall of said cavity in the fully mated position, and a second set of locking arms adapted to enter into the space between said wall extensions causing said wall extensions to flex outward into locking engagement with an adjacent electrical terminal. Finally, means are provided to fix the locking member in a preassembled and a final position, whereby the locking member cannot be placed in the final position unless the terminals are properly and fully seated within the cavities.

For a better understanding of the invention, and to show how it may be carried into effect, reference is made by way of example to the accompanying drawings in which: FIGURE 1 is an exploded perspective view of the electrical connector assembly of this invention, illustrating an electrical connector housing, an exemplary pair of electrical terminals, and an electrical terminal locking member.

FIGURE 2 is an upper perspective view showing the connector housing and locking member in a preassembled position.

FIGURE 3 is a lower perspective view of the assembly shown in Figure 2.

FIGURE 4 is a sectional view of the assembled structure of Figure 1.

FIGURE 5 is a sectional view similar to Figure 4, but illustrating the situation where an electrical terminal is not fully seated within the assembly causing interference to final mating of the locking member to the connector housing.

As best seen in the exemplary embodiment of Figure 1, the electrical connector assembly of this invention comprises a housing member 10, formed of a relatively rigid dielectric material, such as plastic, a terminal locking member 12, and a plurality of electrical terminals 14, two of which are shown, by way of example, prior to loading same into the housing member. Since male tabs have been illustrated for the electrical terminals 14, it will be understood that a complementary connector housing or assembly, containing a like plurality of female receptacles is to be mated therewith. However, for convenience, the further description will be limited to the assembly illustrated in Figure 1.

The housing member 10, in its preferred embodiment, comprises a one-piece housing, formed of a rigid dielectric material, such as plastic, having a first section 16 containing plural through cavities 18, opening to front face 20 for receiving electrical terminals 14. The cavities 18, for the most part arranged in pairs, include a pair of terminal guides 22, in part to facilitate terminal loading of the housing section 16. As best illustrated in Figures 4 and 5, between adjacent pairs of cavities 18, a common cavity wall 24 is provided. Interiorly, the common cavity wall 24 is characterized by a pair of spaced apart extensions 26, which in the relaxed position, i.e. no terminal loading, see Figure 5, the ends 30 of which lie within the space defined by the terminal guides 22. This will be discussed in more detail hereinafter in reviewing Figures 4 and 5.

A further interior feature of each cavity 18 is the provision of a cantilevered terminal locking lance 32 formed integrally with the outer cavity wall 34 and extending longitudinally toward the mating face 36. Each such lance 32 is further provided with a projection 38 or terminal stop, the purpose of which is to engage and secure an electrical terminal 14 loaded in the cavity 18.

An exterior feature of the housing section 16 is the through channel 40 located above the single cavity 18'.

Projecting from each side wall 42 of the channel 40 are a pair of laterally aligned stops 44,46. The purpose thereof will become more apparent in the description of the locking member 12.

The second section 50 of the housing member 10, dimensioned to receive the locking member 12, is a single cavity 52 extending between mating face 36 and the cavity openings 54 into which the male tabs 56 of terminals 14 project for mating purposes.

The locking member 12, dimensioned to fit within the second housing section 50, essentially comprises a top wall 60, a bottom wall 62, and a mating face wall 68. For stability the bottom and top walls may be joined by a pair of supports 70. Projecting externally from the mating face wall 68 about the outer rim thereof is a first set of arms 72, one for each cavity 18,18', and a second set of arms 74,74' laterally disposed along the center thereof. Since the preferred arrangement of the cavities is in pairs, there is a single arm 74 for each pair, and a single arm 74' aligned with the single cavity 18'. The second set of arms 74,74' are characterized by a tapered mating end 76, the purpose of which is to spread the wall extensions 26 in the fully mated position for the locking member 12 and housing member 10 (see Figure 4).Finally, the interior of the locking member 12 may be provided with mating guides 78. That is, they offer stiffening support to the locking member 12, while providing a mating guide or key for the complementary housing member to be mated therewith.

Extending from the channel 66 towards the housing member 10, see Figure 1, is a flexible, cantilevered latching arm 80, angled at a slightly upward angle. The mating end may be provided with a pair of upstanding projections 82 with the forward edges 84 defining a cam follower surface. As will be evident by Figure 2, the projections 82 of latching arm 80, when a positive mating force F is applied to the locking member 12, are caused to enter the channel 40 to first engage the stops 46. This represents the preassembly position (Figures 2 and 3). The stops 46 are elevated above stops 44 so that a smaller positive force F is required to overcome the stops 46.

That is, less flexing of the latching arm 80 is required before it underrides the stops 46. To achieve the fully mated or final position (Figure 4) additional force F is applied between the respective members, whereby the latching arm 80 further penetrates channel 40. As the projections 82 reach stops 44, they are deflected downward until such projections clear the stops 44 and resile to a locked position in front of stops 44, i.e. locked against premature withdrawal.

The electrical terminal 14, as known in the art, typically comprises a one-piece assembly stamped and formed from a sheet metal blank. The electrical terminal includes a wire crimping section 90, a mating end 92 in the form of a flat tab, and a middle section 94, where the crosssection thereof is generally rectangular for proper alignment and seating within the cavity 18,18'. The top of the middle section 94 is characterized by a recess or opening 96 (Figure 1). Likewise, the bottom thereof is formed with an opening 98, where such opening is formed by a section being cut-out and folded over to form a terminal stop 100. The functions of the openings 96,98 will become apparent from a consideration of Figures 4 and 5.

Before considering such Figures, it should be noted that a feature of this invention is that unless each electrical terminal 14 is properly and fully seated within its respective cavity 18, it is impossible to fully mate the locking member 12 with housing member 10. Figure 4 represents the fully mated condition where all electrical terminals are fully seated. There is, the lances 32 are in locking engagement with its corresponding terminal 14 at opening 96, and the arms 72 have seated within the space between said lances 32 and cavity wall 34. Further, the tapered leg 74 has entered between the wall extensions 26, causing such extensions to spread bringing the ends 30 into engagement with the terminal 18. In this position, the ends 30 block any premature withdrawal of the terminals 14 by being positioned behind terminal stop 100.

Turning to Figure 5, it will be noted that the lower terminal T has not been fully seated within the cavity 18.

As a consequence, the lance 32 has been pushed against the wall 34 closing the gap, whereby the arm 72 is prevented from sliding between the lance 32 and wall 34.

Claims

1. An electric connector assembly for mating with a complementary electrical connector, comprising an insulative housing member having a front face at one end and a mating face at the opposite end, plural pairs of through cavities to receive electrical terminals within said assembly, and an electrical terminal locking member insertable into said cavities from said mating face to secure said electrical terminals in a fixed position within said cavities, wherein each cavity is provided with a cantilevered terminal locking lance formed integrally with an outer cavity wall and extending longitudinally toward the mating face, each pair of cavities, along a common inner wall, is provided with two flexible spaced apart wall extensions, said locking member is provided with a first set of locking arms, one for each cavity, where one locking arm is adapted to seat between each locking lance and the adjacent wall of the cavity in the fully mated position, and a second set of locking arms adapted to enter into the space between the wall extensions causing said wall extensions to flex outwardly into locking engagement with an adjacent electrical terminal, and means for fixing the locking member in a preassembled and a final position, whereby said locking member cannot be placed in said final position unless the terminals are properly and fully seated within the cavities.

2. The electrical connector assembly according to claim 1, wherein the position fixing means includes a flexible latching arm that engages a first set of stops to define the preassembled position, and a second set of stops to define the final mated position.

3. The electrical connector assembly according to claim 2, wherein the second set of stops is displaced below the first set of stops, whereby a greater force is required to engage said second set of stops.

4. The electrical connector assembly according to claim 1,2 or 3, wherein the mating ends of locking arms are tapered to facilitate their entry between wall extensions.

5. The electrical connector assembly according to claim 1,2,3 or 4, in combination with electrical terminals provided with recesses to receive said terminal locking lances.

6. An electrical connector assembly constructed and adapted to operate substantially as hereinbefore described with reference to the accompanying drawings.