Electronic connector with CPA device

An electrical connector has a socket connector body that has a lock ramp, a plug connector body that mates with the socket connector body and that has a lock arm that engages the lock ramp of the socket connector body to lock the plug and socket connector bodies together when the connector bodies are mated, and a connector position assurance (CPA) device that is slideably retained on the plug connector body for assuring that the connector bodies are properly mated and locked together. The CPA device has a top wall and depending sidewalls at respective longitudinal edges of the top wall that overlap and slide on spaced side walls of the plug connector body. The lock arm is between the sidewalls of the plug connector body and connected to the side walls midway between its ends to provide a release lever. The top wall of the CPA device has a depending pusher portion at one end for pushing the lock arm into engagement with the lock ramp and a target portion at the opposite end of the top wall for applying a force to the CPA device. The CPA device is retained in a first detent or pre-stage position and a second detent position with respect to the plug connector. The top wall of the CPA device has a release lever that operates the release lever of the lock arm when the CPA device is in the pre-stage position and the target portion of the CPA device has a strap that disables the release lever of the lock arm when the CPA device is in the second detent position.

TECHNICAL FIELD 
This invention relates generally to electrical connectors and more 
particularly to electrical connectors that are equipped with a connector 
position assurance (CPA) device that assures that the electrical 
connectors are properly mated and locked together. 
BACKGROUND OF THE INVENTION 
Existing CPA devices are typically loose pieces that operate as wedges that 
keep the mated electrical connectors locked to each other. See for 
instance, U.S. Pat. No. 4,746,306 granted to John A. Yurtin et al. May 24, 
1988, which discloses a pin-like CPA device for electrical connectors that 
is wedged into a gauge hole that exists only if the electrical connectors 
are properly mated and locked together. U.S. Pat. No. 4,906,204 granted to 
John R. Metzger Mar. 6, 1990, and U.S. Pat. No. 4,946,402 granted to Randy 
L. Fink et al. Aug. 7, 1990, show similar arrangements. 
While these CPA devices have been used successfully, the CPA devices have a 
common drawback in that the CPA devices are loose pieces that can be lost 
or ignored in the assembly process. 
U.S. Pat. No. 4,946,395 granted to Kenneth P. Cope et al. Aug. 7, 1990; 
U.S. Pat. No. 5,026,298 granted to Stacy A. Brussalis et al. Jun. 25, 
1991; U.S. Pat. No. 5,120,255 granted to Tomoyuki Kouda et al. Jun. 9, 
1992, and U.S. Pat. No. 5,605,471 granted to Robert G. Plyler Feb. 25, 
1997, disclose CPA devices that are slideably retained on the connector 
body of one of the matable electrical connectors thus avoiding many of the 
problems associated with CPA devices that are loose pieces. 
While some of these CPA devices have been used successfully, further 
improvements are still desirable and possible. 
SUMMARY OF THE INVENTION 
The object of this invention is to provide an electrical connector that 
includes a CPA device that is slideably retained on the connector body of 
one of the electrical connectors and that has one or more of the following 
features. 
A feature of the invention is that the CPA device is mounted exteriorly on 
the connector body of one electrical connector to provide a pleasing 
appearance. 
Another feature of the invention is that the exteriorly mounted CPA device 
has a wide projection-free outer surface to provide a pleasing appearance 
and avoid snagging. 
Still another feature of the invention is that the CPA device has a pusher 
portion that is attached to a thin flexible wall of the CPA device to 
permit vertical movement of the pusher portion while avoiding projections 
that could cause snagging. 
Yet another feature of the invention is that the CPA device is particularly 
well suited for electrical connectors having a lock arm that pivots 
outward on a connector body midway between it ends to provide a release 
lever. 
Still another feature of the invention is that the CPA device disables the 
release lever of the lock arm when the connectors are properly mated and 
locked together. 
Still another feature of the invention is that the CPA device assists in 
disconnecting electrical connectors that are mated and locked together. 
Still yet another feature of the invention is that CPA device has structure 
that provides strong resistance against the CPA device being pulled off 
the connector body on which it is slideably retained. 
These and other objects, features and advantages of the invention will 
become apparent from the description below, which is given by way of 
example with reference to the accompanying drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to FIG. 1, the electrical connector assembly 100 comprises a plug 
connector 102 and a socket connector 104 that mate and establish an 
electrical connection in a well known manner. Plug connector 102 comprises 
a connector body 106 that plugs into connector body 108 of socket 
connector 104. Connector body 106 contains terminals 110 attached to the 
ends of electrical leads 112. Terminals 110 mate with terminals 114 in 
connector body 108 that are attached to the ends of electrical leads 116 
when connector body 106 is plugged into connector body 108. 
When mated, the plug and socket connectors 102 and 104 are locked together 
by lock arm 118 of connector body 106 engaging a lock ramp 120 of 
connector body 108. Lock arm 118 is located between two spaced upright 
side walls 122 of connector body 106 that are joined by a cross bar 124 at 
the forward end. Lock arm 118 has a longitudinal slot that extends from a 
lock bar 126 at a forward end to a stop bar 128 at a rearward end. Lock 
arm 118 is attached to side walls 122 by torsion pin portions 123 that 
twist resiliently so that lock arm 118 can pivot like a teeter-totter. Pin 
portions 123 are midway between forward lock bar 126 and rearward stop bar 
128 so that the forward portion of lock arm 118 pivots outwardly when the 
forward lock bar 126 engages lock ramp 120 or when the stop bar 128 is 
depressed with the rearward portion of the lock arm 118 acting as a 
release lever. 
Each side wall 122 has a forward lateral rail 130 that extends outwardly 
and a rearward slot that provides a laterally flexible lock arm 132 that 
includes a lock ramp 134 that extends outwardly. 
The electrical connector assembly 100 also includes a connector position 
assurance (CPA) device 140 that insures that the socket and plug 
connectors 102 and 104 are properly mated and locked together. CPA device 
140 is slideably retained on connector body 106 and cooperates with lock 
arm 118 and lock rampl20 as explained below. 
CPA device 140 comprises a generally flat top wall 142 with depending side 
wallsl44 at the respective longitudinal edges. Top wall 142 has a wide 
outer surface that extends between and merges smoothly into side walls 
144. The outer surface is also projection-free to provide a pleasing 
appearance and avoid snagging. Each side wall 144 has an inwardly facing 
longitudinal groove 146 that receives one of the lateral rails 130 of 
connector body 106 so that the CPA device 140 slides on connector body 106 
in a longitudinal direction. 
Top wall 142 has a depending pusher portion 148 at the forward end and the 
front portion of top wall 142 that carries the pusher portion 148 is thin 
to provide sufficient flexibility for the depending pusher portion 148 to 
be moved vertically with respect to the side walls 144 in the connection 
sequence as explained below. 
Top wall 142 has two laterally spaced longitudinal slots in the rearward 
portion that form a depressible release lever 150 that is connected to the 
rearward portions of side walls 144 by a thin, flexible strap 145. Lever 
150 includes two laterally spaced lock nibs 152 that extend inwardly in 
alignment with stop shoulders 154 on the face of stop bar 128. Lock nibs 
152 snap over and engage stop shoulders 154 when CPA device 140 is 
assembled to the connector body 106 so that the CPA device 140 is 
slideably retained on connector body 106. Two lock nibs 152 engage two 
stop shoulders 154 in a flat perpendicular engagement to provide a strong 
resistance against CPA device 140 being pulled off connector body 106. 
The rearward portions of side walls 144 are deeper to accommodate a second 
inwardly facing groove that is below the slide groove 146 and that 
includes a lock nib 156 with forward and rearward slanted faces. Forward 
faces of lock nibs 156 engage rearward faces of lock ramps 134 of 
connector body 106 when CPA device 140 is assembled to the connector body 
106. Thus CPA device 140 is retained in a first detented or "pre-staged" 
position by lock nibs 152 and stop shoulders 154 of stop bar 128 in one 
direction, i.e. the pull-off direction and in the opposite push on 
direction by lock nibs 156 and lock ramps 134. The deeper rearward 
portions of side walls 144 are connected by a relatively rigid cross strap 
158. 
The first detented or pre-staged position is shown in FIG. 2. In this 
position CPA device 140 has an annular target portion 160 at the rear end 
that overhangs connector body 106 as shown in FIG. 2. When plug connector 
102 is plugged into socket connector 104, CPA device 140 is pushed 
forwardly on connector body 106 by applying a thumb force to the annular 
target portion 160 until the connectors are properly mated and locked 
together. 
The connection sequence is shown in FIGS. 3A, 3B, 3C and 3D. As the CPA 
device 140 is pushed forward, pusher portion 148 engages lock bar 126 of 
lock arm 118 as shown in FIG. 3A if lock bar 126 is not already properly 
seated behind lock ramp 120 when plug and socket connectors 102 and 104 
are mated. Pusher portion 148 then pushes lock bar 126 up onto lock ramp 
120 of connector 104 as shown in FIG. 3B. As CPA device 140 continues 
forwardly, pusher portion 148 is raised by the lock ramp 120 and then 
disengaged from lock bar 126 when lock bar 126 is pushed to the locked 
position behind lock ramp 120 as shown in FIG. 3C. Lock bar 126 then 
engages ramp 162 of pusher portion 148 to raise pusher portion 1.48 out of 
the lock arm slot and allow pusher portion 148 to continue moving forward 
until it engages cross bar 124 as shown in FIG. 3D. CPA device 140 is then 
held in this second detented position by rearward faces of lock nibs 156 
engaging forward surfaces of lock ramps 134. 
It should be noted that CPA device 140 cannot be pushed to the second 
detented position unless connectors 102 and 104 are properly mated and 
locked together with lock bar 126 located behind lock ramp 120. 
Furthermore in this second detented position where the electrical 
connectors 102 and 104 are properly mated and locked together, the 
relatively rigid cross strap 158 is below the rear end of lock arm 118 so 
that the rearward portion of lock arm 118 cannot act as a release lever 
and disengage lock bar 126 from lock ramp 120. 
When disconnecting connectors 102 and 104, CPA device 140 is pulled back to 
the first detented or pre-staged position shown in FIG. 2 while the lock 
bar 126 is still engaged behind lock ramp 120. The rearward portion of 
lock arm 118 can now act as a release lever because cross strap 158 is 
positioned behind lock arm 118. Lock bar 126 is then easily disengaged 
from lock ramp 120 by depressing release lever 150 of CPA device 140 which 
acts on the rearward portion of lock arm 118 with a mechanical advantage 
due to the overhanging position of target portion 160. Once lock arm 118 
is released, connectors 102 and 104 can be pulled apart easily. 
Obviously, many modifications and variations of the present invention in 
light of the above teachings may be made. It is, therefore, to be 
understood that, within the scope of the appended claims, the invention 
may be practiced otherwise than as specifically described.