EP0767515A2

EP0767515A2 - Electrical connector having front loadable secondary locking member

Info

Publication number: EP0767515A2
Application number: EP96115451A
Authority: EP
Inventors: Alan John Beken; Maganlal Mistry
Original assignee: Whitaker LLC
Current assignee: Whitaker LLC
Priority date: 1995-10-03
Filing date: 1996-09-26
Publication date: 1997-04-09
Also published as: EP0767515A3; GB9520188D0

Abstract

An electrical connector (2) comprising a connector housing (4) and a locking member (6) where the connector housing (4) includes a contact cavity (10) for receiving an electrical contact and has a retention arm (40) that is deflectable to allow the contact to be inserted into the cavity (10) and after the contact passes thereby resiles therebehind, the locking member (6) having a wedge (34) extending therefrom where the locking member (6) has a first position relative the connector housing (4) such that the retention arm (40) is deflectable to allow the contact to pass and a second position where the wedge (34) is located behind the retention arm (40) and prevents deflection thereof, the connector (2) being characterized in that the wedge (34) includes an abutment shoulder (54) along the backup surface (48) that is oriented transversely to the direction of insertion of the locking member (6) such that the abutment shoulder (54) stubs the retention arm (40) if the retention arm (40) is in a deflected position, thereby preventing the locking member (6) from achieving the second position and where the locking member 40 further includes a resilient tab (26) that interferes with the connector housing 4, thereby preventing insertion thereof to the second position unless deflected.

Description

This invention relates to electrical connectors and in particular to electrical connectors having a front loadable locking member to assure the electrical contacts loaded therein are positively retained.
In the electrical connector industry it is common to utilize a front loadable locking member to assure contacts are retained within the connector housing. One particular example of a connector of this type is disclosed in U.S. Patent 4,708,662. The electrical connector described therein includes a housing having a cavity for receiving an electrical contact therein, where extending from the cavity walls are contact retention arms that act to positively retain in position the contact by fitting behind a shoulder thereupon, thereby preventing the contact from backing out. A locking member is fitable upon the front of the housing and includes a first position where contacts may be loaded into the connector housing by deflecting the arms and a second position where the arms are backed-up by wedges extending from the locking member to fit behind the arms. These wedges extend sufficiently forward so that in the first position they overlap respective arms of the connector housing, thereby preventing the arms from deflecting behind their retention wedges.
Electrical connectors of the type described above, perform admirably; however, there is still a problem that it is occasionally possible to fully insert the secondary locking member to its second position without having the electrical contacts properly positioned within the housing. This may occur due to the shallow angles that are typically involved with the engagement arms and their cooperating wedges. An additional problem, is that housings are typically manufactured from a soft plastic material and the contacts are formed from metal so that if the mating plastic parts are forced together, the retention shoulders on the arms may be deformed. Finally, the deformation is especially prevalent in high density connectors where the contacts, passageways, and associated shoulders of the retention arms are relatively small in size. Therefore, it would be advantageous to provide assurance that the secondary locking member could not be displaced to its second position unless the retention arms are in the locked position behind the shoulder of the contact. It would be further advantageous if this provision could be provided without dramatic changes to the connector assembly as connectors of this type have received widespread use.
These and other objects are accomplished by providing an electrical connector comprising a connector housing and a locking member where the connector housing includes a contact cavity for receiving an electrical contact that has a retention arm extending from a wall thereof to a free end that carries a stop shoulder thereupon, the stop shoulder being formed to cooperate with a shoulder of the contact when inserted therein to prevent displacement thereof and where the retention arm is deflectable to allow the contact to be inserted into the cavity and after the contact passes thereby resiles therebehind, the locking member having a wedge extending therefrom that includes a backup surface and where the locking member has a first position relative the connector housing such that the retention arm is deflectable to allow the contact to pass and a second position where the wedge is located behind the retention arm and prevents deflection thereof, the connector being characterized in that the wedge includes an abutment shoulder along the backup surface that is oriented transversely to the direction of displacement of the locking member such that the abutment shoulder stubs the retention arm when the retention arm is in a deflected position, thereby preventing the locking member from achieving the second position unless the retention arm is in an undeflected position.
In connectors of the fore going type and other connectors that utilize a locking member having a first position upon the connector housing and being displaceable to a second position in order to assure contacts are retained therein, another problem may be faced. Using the fore going as an example, the locking member may be displaced into a locking position whenever the arms are in a undeflected position. This undeflected position is also obtainable when the electrical connector is being transported to the user prior to loading contacts therein. While the first position is a temporary position, the second or locked position is meant to be relatively permanent and therefore the associated latching members are difficult to disengage. It is a time consuming and difficult procedure that is disruptive to assembly techniques when a connector housing that is to be loaded with contacts is delivered to an assembly station already in the second position. Therefore, what is needed is a simple and economical feature to assure that the locking member is not accidentally displaced from the first to the second position. It is further required that this be a simple and unintrusive addition to the components of the connector.
These and other objects are accomplished by providing an electrical connector comprising a connector housing having a contact cavity therein for receiving a contact and a locking member for assuring the contacts are positively retained in the connector housing, the locking member having a first position upon the housing where the contact is receivable in the cavity and a second position where the locking member effects obstruction of the cavity, thereby preventing insertion or assuring retention of the contact, the connector being characterized in that a resilient tab is provided on the locking member that interferes with the connector housing, unless deflected, when moving between the first and second positions.
The invention will now be described by way of example with reference to the drawings, wherein:

Figure 1 is an upper perspective view of an electrical connector according to the present invention;
Figure 2 is an upper perspective view of the locking member incorporated into the connector of Figure 1;
Figure 3 is a side sectional view of the electrical connector of Figure 1 with the locking member in the first position;
Figure 4 is a side sectional view corresponding to that of Figure 3 showing the electrical connector of Figure 1 with the locking member in a second position;
Figure 5 is another side sectional view of the electrical connector of Figure 1 showing the locking member in the first position of Figure 3; and
Figure 6 is a detailed view of a locking wedge incorporated into the locking member of the connector of Figure 1.

With reference first to Figure 1, an electrical connector according to the present invention is shown generally at 2. The electrical connector 2 includes a connector housing 4 and a locking member 6. In this example, the electrical connector 2 is configured as a relay housing and includes a resilient arm 8 for positively retaining the relay (not shown). The invention is not to be limited by the configurations described herein. A plurality of contact receiving passageways 10 are open through the locking member 6 for receiving a mating contact (not shown). The locking member 6 is receivable into an opening 12 in the connector housing 4 that is defined by outer walls 14 that further define an upper surface 16 thereof.
With reference now to Figure 2, the locking member 6 will be described in greater detail. The locking member 6 includes a supporting plate 18 having openings 20 therein that are in communication with the contact cavities 10 when the locking member 6 is mounted upon the connector housing 4. Extending from one side of the support plate 18 is a shroud 22 that is bifurcated such that side portions 24 are freely cantilevered from a base wall 25. Each side portion 24 includes a tab 26 carried thereupon that extends outwardly therefrom in an L-like manner. The tab 26 is free from an upper wall portion 28 opposite the base wall 25, thereby enabling the side portions 24 to be resiliently deflectable such that displacement of the tabs 26 may be achieved. Multiple latching arms 30 extend from the opposite side of the support plate 18 and include a hook portion 32 for engaging catch surfaces upon the connector housing to define both a first position for the locking member 6 and a second position for the locking member 6 that are displaced from each other. Further included in the locking member 6 and extending in the same direction as the locking arms 30 are wedge members 34 that will be described in greater detail below.
With reference now to Figure 3 and Figure 4, the electrical connector 2 is shown assembled in the first and second position respectively. As shown in Figure 3, one of the latch arms 30 is engaged with a first position catch 36 so that the locking member 6 is prevented from being displaced from the connector housing 4. The locking member 6 is shown positioned above the opening 12 that is defined by the side walls 14. In this position, the side walls 24 carrying the tabs 26 are in their free position such that the tabs 26 extend out over the upper surface 16 of the connector housing 4. As can be easily imagined, exertion of a force in the direction of arrow A, without first deflecting the tabs 26, results in abutment of the tabs 26 with the upper surface 16, thereby preventing the locking member 6 from being further inserted into the opening 12. Ultimately, the second position cannot be achieved as the tabs 26 interfere with the upper surface 16 of the housing 4. With reference now to Figure 4, the freely cantilevered side arms 24 may be deflected in a way such that the tabs 26 may be received within the opening 12 without interference with the side walls 14 or the upper surface 16 carried thereupon. In this instance, another one of the latching arms 30 of the locking member 6 engage a second lock position catch surface 38 in order to establish the second position of a connector 2.
With reference now to Figure 5, the contact retention will be described in detail. As shown, the locking member 6 is affixed upon the housing 4 in the first position. The connector housing 4 includes the contact cavities 10 which from a wall thereof protrudes a cantilevered contact retention arm 40. The retention arm 40 has a free end 42 carrying a stop shoulder 44 that cooperates with a corresponding shoulder of an electrical contact to be inserted therein in a manner that is well known. As the retention arm extends slightly away from the cavity wall 39, a space 46 is defined therebetween.
The wedges 34 that extend from the locking member 6 are described in detail with reference also to Figure 6. The wedge 34 includes a backup surface 48 that may be inclined to correspond to the angle at which the retention arm 40 extends from the wall 39. Opposite the backup surface 48 is a support surface 50 that corresponds to the cavity wall 39. The wedge further includes a free end 52 that is configured to fit within the space 46. The backup surface 48 is truncated in such a manner that an abutment shoulder 54 is provided that is generally transverse to the wedge 34. The truncation further defines the free end 52 as a nose portion 56 that when the locking member 6 is in the second position, as shown in Figure 5, the nose 56 overlaps the free end 42 of the retention arm such that it is not possible for the retention arm 40 to be displaced behind the wedge 34. This assures that the free end 42 will either interfere with the abutment shoulder 54 if it is not returned to its original and natural position or the wedge 34 will fit between the retention arm 40 in the wall 39 thereby maintaining the retention arm 40 in engagement with the contact in the contact cavity 10. The stop shoulder 54 provides for clean stubbing or abutment with the free end 42 of the retention arm 40 that prevents further insertion of the locking member 6 without the possibility that the gradual backup surface 48 would interact with the free end 42 to deform the arm 40 or the stop shoulder 44.

Claims

An electrical connector (2) comprising a connector housing (4) and a locking member (6) where the connector housing (4) includes a contact cavity (10) for receiving an electrical contact where a retention arm (40) extending from a wall thereof to a free end (42) and that carries a stop (44) thereupon, the stop (44) being formed to co-operate with the contact to prevent extraction thereof, where the retention arm (40) is deflectable to allow the contact to be inserted into the cavity (10) and after the contact passes resiles therebehind, the locking member (6) having a wedge (34) extending therefrom that includes a backup surface (48) and where the locking member (6) has a first position relative the connector housing (4) such that the retention arm (40) is deflectable to allow the contact to pass and a second position where the wedge (34) is located behind the retention arm (40) and prevents deflection thereof, the connector being characterized in that the wedge (34) includes an abutment shoulder (54) along the backup surface (48) that is oriented transversely to the direction of displacement of the locking member (6) such that the abutment shoulder (54) stubs the retention arm (40) when the retention arm (40) is in a deflected position, thereby preventing the locking member (6) from achieving the second position unless the retention arm (40) is in an undeflected position.
The electrical connector of claim 1, further characterized in that the locking member (6) is telescopically disposed on the connector housing (4), where the locking member includes a plurality of latch arms (30) at least one of which engages a first shoulder (36) in the first position and a second shoulder (38) in the second position.
The electrical connector of claim 1 or 2, further characterized in that the wedge (34) further including a nose (56) extending beyond the abutment shoulder (54) such that in the first position the nose 56 is in an overlapping relation with the free end (42) of the retention arm (40).
The electrical connector of claim 1, 2 or 3, further characterized in that the connector includes a deflectable tab (24) including an abutment (26) that prevents movement of the locking member (6) from the first position to the second position unless deflected.
The electrical connector of claim 4, further characterized in that the deflectable tab 24 is attached to the locking member (6) and the abutment (26) interfering with an upper surface (16) of the housing (4) unless deflected.
An electrical connector (2) comprising a connector housing (4) having a contact cavity (10) therein for receiving a contact and a locking member (6) for assuring the contacts are positively retained in the connector housing (4), the locking member (6) having a first position upon the housing (4) where the contact is receivable in the cavity and a second position where the locking member (6) effects obstruction of the cavity, thereby preventing insertion or assuring retention of the contact, the connector being characterized in that a resilient tab (24) is provided on the locking member (6) that interferes with the connector housing (4), unless deflected, when moving between the first and second positions.