Field of the Invention
[0001] The present invention relates to an electrical connector for use with igniters for
vehicle occupant inflatable restraint systems, generally known as airbags, and in
particular, to means for maintaining the connector plug in engagement with the socket.
Background of the Invention
[0002] The use of airbag systems in motor vehicles has become virtually universal in recent
years, and is mandatory in many jurisdictions. Such systems normally include an airbag
assembly mounted in a hidden compartment beneath the dashboard, and an electrical
or electronic control system for activating the assembly upon the occurrence of a
crash. The airbag assembly is generally connected to the control system by a wiring
harness provided with a plug with socket contacts and a socket which receives pin
contacts of the igniter.
[0003] A connector system of this type is shown, for example, in EP 0 591 947, in which
the system is associated with an interlock including a locking element which is inserted
into the connection to prevent separation of a pair of male connector elements carried
by a first component from a pair of female connector elements carried by a second
component and releasably mated therewith. A shorting element is associated with the
first component and includes a pair of contact elements each biased into electrical
contact with one of the pair of first connector elements for producing a short therebetween.
The second component has a body comprising a portion contoured to enter between the
pairs of connector elements so as to disconnect the short upon mating of the first
and second components, which are mechanically latched together. The locking element
prevents release of the latch and hence separation of the two components while in
the lock position.
[0004] In EP 0 537 751, which relates to a switch connector assembly with a waterproof structure
which prevents the admission of water, the female connector has a short-circuiting
terminal extending into a connector fitting chamber thereof, as well as a temporary
attesting projection and a flexible locking arm with a final arresting projection.
The male connector has a connecting terminal, a flexible engaging pawl, and an engaging
portion. When the temporary arresting projection is fitted with the pawl, the short-circuiting
terminal is kept out of contact with the connecting terminal, but the two terminals
enter into contact when the final attesting projection is fitted with the engaging
portion.
Summary of the Invention
[0005] The connector according to the present invention comprises a plug part with socket
contacts which have a wire connection side for attachment of wires and a pin receiving
side for receiving pin contacts projecting from the airbag igniter. The pin contacts
extend from a socket part located on the igniter. Once the connector has been mated
with the igniter, it can only be unmated with the aid of a special removal tool.
[0006] The plug part is provided with a snap on cover which assures retention of the cable
and which is provided with lateral and front resilient locking lugs, as well as a
downwardly projecting element which engages a complementary aperture in the socket
part to permit 360° positioning of the plug in the igniter socket and the application
of torque force. The cover maintains the socket contact in position. In addition,
the downwardly facing side of the end of the cover opposite the downwardly projecting
element is provided with nipples which bite into the wire-insulating cable in order
to assure its retention on the U-shaped rear portion of the plug part.
[0007] It is an object of the present invention to improve the means for retaining the plug
part in the socket part, specifically by means of resilient locking arms which extend
from the base of the plug part, and which spread apart to self-lock in a locking slot
in the socket part as a pull-out force is applied to the plug part.
Brief Description of the Drawings
[0008] In order that the invention may be more clearly understood, reference will now be
made to the accompanying drawings, in which an embodiment of the invention is shown
for purposes of illustration, and in which:
Figure 1 is a front elevation view of the plug part and the igniter socket part in
unassembled position;
Figure 2 is a front elevation view of the plug part and the igniter socket part in
assembled position;
Figure 3 is a top plan view of the plug part with its cover along line A--A of Figure
1;
Figure 4 is a plan view of the cover showing the locations of the lateral and front
resilient locking lugs;
Figure 5 is a front elevational view of the cover;
Figure 6 is a partly-sectional front elevation view of the cover;
Figure 7 is a rear end view of the plug and the cover in unassembled position;
Figure 8 is a detail view of the resilient locking arms; and
Figure 9 is a view similar to Figure 8, showing locking arms according to the prior
art.
Detailed Description
[0009] Figs. 1 to 7 illustrate a connector plug 1 with downwardly extending socket contacts
2 with a wire connection side 3 for the attachment of cable-clad wires 4 and a pin-receiving
side 5 beneath the socket contacts.
[0010] In order to assure the retention of the cables 4 containing the conductor wires ,
plug 1 is surmounted by a cover 9 with lateral locking lugs 10 and resilient front
locking lugs 11. The underside of the rear end of cover 9 is further provided with
nipples 12 which bite into the cables to prevent them from shifting longitudinally
in the U-shaped rear portion of the plug.
[0011] Plug 1 is designed to mate with a socket part 8 located on the airbag igniter 7 and
comprising pin contacts 6 which mate with sockets 2.
[0012] To permit 360° positioning and the application of torque force, the forward part
of plug 1 is provided with a downwardly projecting arm 40 which engages in a complementary
aperture 50 extending downward from the top surface of the socket part 8.
[0013] To assure retention of plug 1 in socket 8, the plug is provided with a pair of downwardly
extending, substantially vertical resilient locking arms 21 provided with lateral,
outwardly facing detent projections 17, each comprising an upwardly divergent outer
surface 17a and a horizontal upper surface 17b which abuts against a corresponding
downwardly facing surface of a locking slot 30 provided in socket 8. When an upward
pull-out force is applied to plug 8, resilient arms 21 spread apart and self-lock
in locking slot 30.
[0014] The locking arm arrangement of the present invention, as shown schematically in Fig.
8, is a significant improvement over that of EP 0 537 751, as shown in Fig. 9, in
which locking arms 27, while also provided with detent projections 26, do not flex
outwardly and hence cannot perform the self-locking function of applicants' locking
arms 21. The invention hence results in a more secure interengagement of the plug
and socket, this being critical in the case of airbag igniter connectors.
1. An electrical connector assembly comprising a plug member (1) having first contact
means (2) adapted to mate with a socket member (8) having second contact means (6),
one of said plug member (1) and said socket member (6) comprising resilient locking
means (20) adapted to engage in an aperture (30) in the other of said plug member
(1) and said socket member (8), said resilient locking means (20) comprising at least
two arms (21) which, upon application of a force to effect separation of said plug
member (1) from said socket member (8), spread apart so as to self-lock and to prevent
said separation.
2. An electrical connector assembly according to claim 1, wherein said resilient locking
means (20) project vertically from a bottom of said plug member and engage in a locking
slot (30) in said socket member (8).
3. An electrical connector assembly according to claim 2, wherein said arms (21) comprise
detent means including upwardly divergent portions joining horizontal portions which
abut under a shoulder of said locking slot (30) and prevent disengagement of said
plug member (1) from said socket member (8) upon spreading of said arms (21) when
said force is applied.
4. An electrical connector assembly according to claim 1, wherein said plug member (1)
comprises socket contacts (2) having a first side (3) for attachment of a wire connection
and a second side for receiving pin contacts (6) projecting from an airbag igniter.
5. An electrical connector assembly according to claim 1, wherein said plug member (1)
is surmounted by a cover (9) with lateral locking lugs and resilient front locking
lugs for retaining in position a cable enclosing conductor wires.
6. An electrical connector assembly according to claim 5, wherein said cover (9) has
an underside provided with downwardly extending nipples (1) adapted to bite into said
cable (4) to assist in retention of said cable (4).
7. An electrical connector assembly according to claim 1, including an element (40) projecting
downwardly from said plug member (1) and engaging in an aperture (50) in said contact
member for the purpose of assuring 360° positioning and permitting the application
of torque force to said members (1, 8)