Self-aligning cover for modular tricoupler

A wall outlet (20), which facilitates the interconnection of lengths of inside wiring to a network interface device, includes provisions for receiving a modular plug (31) which terminates a cord (32) that is connected to customer station equipment. The wall outlet includes a tricoupler (30) and a cover (25). The tricoupler includes a housing (80) having first and second generally opposed plug-receiving cavities (82, 83) and a third cavity (87). A plurality of metallic wire-like contact elements (90-90) are disposed in the housing of the tricoupler and are engaged by blade-like terminals (60-60) of modular plugs which are inserted into the cavities. The cover includes latching tabs (164-164) which are adapted to be received in grooves (163-163) of the tricoupler housing to secure the tricoupler to the cover. The cover is provided with alignment facilities for causing an opening (162) in the cover to become aligned with the third cavity and the latching tabs with the housing grooves as the tricoupler is secured to the cover.

TECHNICAL FIELD 
This invention relates to a a self-aligning cover for a modular tricoupler 
and, more particularly, to a modular tricoupler which is used for inside 
wiring such as telephone service cables, for example, and which is adapted 
to be secured to a self-aligning cover. 
BACKGROUND OF THE INVENTION 
Modularity is used widely in telephone communication systems. In a modular 
system, a modular plug which terminates an end of a telephone cord is 
inserted into a cavity of a modular jack which is mounted in a wall outlet 
or in portions of customer station equipment. Typically, a home is 
equipped with any number of wall outlets each of which includes a modular 
jack. This allows the customer to move a telephone from room to room and 
allows the customer to purchase and to install new telephones and new 
cords as desired. 
A typical telephone wiring system includes a network interface device, a 
plurality of wire junction devices and wall outlets distributed about the 
rooms of a home, for example. Inside wiring which includes a relatively 
small number of insulated conductors enclosed in a plastic jacket is run 
from any entry junction device which is fed from the interface to a 
plurality of wall outlets. A line is also run friom the entry wire 
junction device to another junction device to which additional wall 
outlets are connected. Typically, the plastic jacket must be removed from 
each end of a length of inside wiring to permit connection of the 
conductors to the junction devices and wall outlets. There has been a 
desire to improve the just-described system to simplify the wiring and to 
provide multiple circuit paths to each wall outlet to decrease the 
probability of service outage. 
For many years, installation service was provided by a telephone operating 
company to each customer premises as requested initially with wiring runs 
to additional rooms as requested subsequently. Each additional outlet 
required a visitation by a craftsperson of the telephone operating 
company. With the advent of modularity, it no longer became necessary for 
a craftsperson to visit customer premises to connect a telephone into the 
network. However, this was only true if modular outlet devices had been 
provided in or on the walls. This led to programs intended to pre-wire 
customer premises for telephone usage with modular outlet devices 
positioned in preselected locations during the construction of the 
premises. Other developments in telephone communications have led to the 
probable situation where inside wiring may be installed by craftspeople 
other than telephone operating company personnel. 
These developments have led to the desire for more simplistic devices for 
use in modular wiring systems. Goals include the use of lengths of inside 
wiring which have been terminated with modular plugs. The plugs which 
terminate the wiring may be secured to the wiring in a factory environment 
or in the field. The lengths are connected end to end with the use of a 
coupler such as that disclosed and claimed in U.S. Pat. No. 4,268,109 
which issued on May 19, 1981 in the name of E. C. Hardesty. An end of each 
run of wiring should be easily connectable to the sought-after wall outlet 
device to which a plug of customer station equipment is also connectable. 
Such a device includes a tricoupler, which is disclosed in copending 
commonly assigned application Ser. No. 442,931 which was filed on even 
date herewith in the name of E. C. Hardesty. 
The tricoupler disclosed in the above-identified application may be secured 
to a cover. The cover is provided with latching tabs which cooperate with 
grooves in sides of a housing of the tricoupler to secure the housing to 
the cover. Then the cover is secured to a receptacle which causes the 
tricoupler to be disposed in the receptacle. If the customer or 
craftsperson making the installation is not careful when securing the 
cover to the receptacle, one of the latching tabs could be inserted 
inadvertently into an outwardly facing jack cavity of the housing. This 
could result in damage to the relatively fragile wire-like contact 
elements disposed within the jack cavity. The same problem may occur 
should the tricoupler be secured to a baseboard molding and the cover 
secured to the tricoupler. 
SUMMARY OF THE INVENTION 
The foregoing problem has been overcome by the modular tricoupler and cover 
of this invention. The tricoupler comprises a housing which is made of a 
dielectric material and which includes first, second and third modular 
plug-receiving cavities spaced about the housing. A wire-like contact 
element is mounted in the housing. When modular plugs are inserted into 
the cavities, blade-like terminals of the plugs engage end portions and/or 
an intermediate portion of the contact element to establish electrical 
contact therewith. Typically, the tricoupler includes a plurality of 
contact elements corresponding in number to the terminals within a modular 
plug to be received in one of the cavities. Two of the cavities generally 
are opposed to each other and receive plugs which terminate service wiring 
that is run inside walls of a customer's home or along a baseboard 
molding. The third cavity is adapted to receive a modular plug that is 
connected to customer station equipment. 
A cover is adapted to be secured to the tricoupler such that the third 
cavity of the tricoupler is exposed to receive a modular plug that 
terminates a cord that is connected to the customer station equipment. The 
cover includes facilities for causing an opening therethrough to become 
aligned with the tricoupler customer cavity during the assembly process. 
Camming wedges may be provided to cam the cover into alignment with the 
tricoupler. 
A wall outlet of this invention includes a receptacle which generally is 
made of a plastic material and which is securable within a wall. An open 
side of the receptacle faces outwardly into a room wherein there is 
located customer equipment to be connected to a network. A plastic cover 
is attachable to the receptacle and includes a pair of latching tabs for 
snaplocking into grooves in the side of the tricoupler housing for 
securing a modular tricoupler to the cover. One cavity of the tricoupler 
communicates through an opening in the cover to the room to receive a 
modular plug of the equipment. The other two cavities in the tricoupler 
are adapted to receive plugs of inside wiring that connect the customer 
equipment to the network. The cover includes an alignment fence which 
circumscribes the tricoupler housing as the tricoupler is secured to the 
cover and which prevents the latching tabs from entering the one cavity of 
the tricoupler.

DETAILED DESCRIPTION 
Referring now to FIG. 1, there is shown a wall outlet, which is designated 
generally by the numeral 20 and which provides to a customer access to a 
telecommunications network. The wall outlet 20 includes a receptacle 23, a 
cover 25 of this invention and a tricoupler 30, which is described and 
claimed in priorly identified E. C. Hardesty application Ser. No. 442,931 
filed on even date herewith. The wall outlet 20 allows a customer to 
insert a modular plug 31 of a cord 32 (see FIG. 2) that extends to station 
equipment into a customer cavity of the tricoupler and to interconnect 
inside wiring 33. 
A telephone set 34 (see FIG. 2) to be interconnected to the wall outlet 20 
through the cord 32 includes a base and a handset that are interconnected 
by a retractile cord 35. The ends of the cord 35 are terminated with 
modular plugs 31--31 which are received in jacks 36--36 in the base and in 
the handset. The modular plug 31 may be that shown, for example, in U.S. 
Pat. No. 4,148,539 which issued on Apr. 10, 1979 in the name of E. C. 
Hardesty while the jack 36 may be that shown for example, in U.S. Pat. No. 
3,990,764 which issued Nov. 9, 1976 in the name of C. L. Krumreich, both 
of which patents are incorporated by reference hereinto. 
The wall outlet 20 is used to facilitate inside communications wiring, 
particularly residential. Because of the modular tricoupler 30, the wiring 
of a home, for example, is done more simply than before. Lengths of inside 
service wiring are terminated at each end with a modular plug 31 which is 
insertable into a tricoupler 30 to interconnect the customer station 
equipment to the network. The modular tricoupler 30 is adapted to 
interconnect the modular plugs 31--31 which are used to terminate the 
small pair size inside wiring in the walls or along the baseboard molding 
and the line cord 32 from the customer station equipment. 
Going now to FIG. 3, there is shown in detail the construction of the 
modular plug 31 which is used to terminate the cords and the inside 
wiring. The plug 31 includes a body 51 having an aperture 52 for receiving 
an end portion of a cord or of a length of inside wiring. The plug 31 is 
also constructed with strain relief portions 53 and 54 for securing the 
jacket and the individual conductors of the telephone cord within the body 
51. Each of a plurality of terminal-receiving slots 56--56 in the plug 
body 51 is adapted to receive a blade-like terminal 60. Each terminal is 
made from an electrically conductive resilient material and has 
insulation-piercing tangs 62--62 protruding therefrom to provide an 
electrical connection between the conductive portion of a conductor and 
the terminal. An edge surface 63 having curved crowns 64--64 completes the 
connection between the associated conductor of the cord and an associated 
contact element within the modular tricoupler 30. 
Formed integrally with the modular plug body 51 is a resilient locking tab 
70 (see again FIG. 3) which extends angularly from the plug body. The tab 
70 is connected by a plastic hinge to a nose 72 of the plug body 51. A 
free end of the tab 70 extends beyond the cord-input end of the plug body 
51 when the tab is in its non-depressed position. The nose 72 has a width 
which is less than that of the plug body 51 and is spaced from the side 
surfaces of the plug body 51 by stepped recesses having faces 73--73. A 
portion 74 is stepped to form shoulders 75--75 having vertical latching 
surfaces 76--76 that are joined to flats 78--78 along edges 79--79. 
As can be seen in FIG. 4, the modular tricoupler 30 includes a housing 80 
having generally opposed first and second plug-receiving cavities 82 and 
83 at end portions 84 and 86, respectively and a third cavity 87. The 
housing 80 is made from a dielectric material such as, for example, 
polycarbonate, rigid polyvinyl chloride (PVC), acrylonitrile butadiene 
styrene (ABS), a composition including ABS and PVC, DELRIN.RTM. acetal 
plastic, or polyamide nylon plastic. The housing 80 is also provided with 
laterally extending lugs 85--85 which are used for mounting the tricoupler 
in engagement with supporting surfaces. 
The tricoupler 30 also includes a plurality of metallic contact elements 
90--90. The contact elements 90--90 may be made from a resilient metallic 
material such as, for example, Phosphor bronze alloy. The contact elements 
90--90 make electrical connections with terminals 60--60 of modular plugs 
31--31 that have been inserted into the cavities 82, 83 and 87 of the 
housing 80. Consequently, the contact elements 90--90 function to connect 
electrically the modular plug of customer station eqiupment to inside 
wiring or to interconnect inside wiring in series through a wall outlet or 
both. 
In a preferred embodiment, the housing 80 of the tricoupler 30 is 
unipartite and includes a cover 91 and a base 92, and sidewalls 93 and 94. 
A plurality of partitions 96--96 extend from a surface 89 internally 
through the housing 80. The partitions 96--96 are maintained spaced apart 
by a plurality of separators 97--97 which are interposed between the 
partitions. The partitions 96--96 and the separators 97--97 provide 
compartments for receiving the contact elements 90--90 to maintain them 
spaced apart and to provide suitable dielectric protection therebetween. 
As can be seen in FIG. 4, the molded cavities 82, 83 and 87 of the modular 
tricoupler 30 are generally identical and each include facilities for 
locking in a modular plug 31. The sidewalls of the housing which define 
each cavity are formed to include an abutment 101 having a vertical face 
102. The vertical face 102 intersects a first ledge 103 which extends to 
the open end of the cavity. A second ledge 104 which is closer to an 
outwardly facing surface of the housing, such as the surface 106, then the 
ledge 103 extends from the partitions 96--96 to a surface 107 to which the 
cavity opens. A ceiling 105 is spaced from the ledges 103--103 a distance 
which is substantially equal to the distance between the surfaces that 
defines the height of the plug body 51. 
In order to allow the tab 70 of the modular plug 31 to assume a normal 
position after insertion into a cavity of the tricoupler 30, each wall of 
the housing 80 which defines each cavity is formed to include a third 
ledge 111. Each ledge 111 is interrupted by an opening 113 having a 
rectangular cross-section and extending from an exterior surface. Those 
side ledge surfaces along which the shoulders 75--75 ride are interrupted 
so that at full insertion of the plug 31, portions of the shoulders clear 
those ledges allowing the arched tab 70 to resume its original orientation 
because of its resilience. 
This structural arrangement of surfaces defining each cavity 82, 83 and 87 
facilitates the receipt and the holding of a modular plug 31 and its 
facile withdrawal by a customer, if desired. When a modular plug 31 is 
inserted into one of the cavities, the tab 70 thereof is depressed and 
bent and has an arched configuration as the flats 78--78 of the shoulders 
75--75 engage and ride along the ledge portions 111--111. At the same 
time, the underside of the plug body 51 is moved slidably along the ledges 
103--103. The inward movement of the plug body 51 is discontinued when the 
faces 73--73 of the recesses engage the surface 102 that extends between 
the abutment 101 and the ledges 103--103. As the shoulders 75--75 of the 
plug tab 70 pass vertically oriented surfaces 117--117 of the openings 
113--113, the resilient tab 70 returns to its normal undeflected position 
causing the shoulders to become disposed in the interrupted portions of 
the sidewalls along the ledges 111. The arrangement resists withdrawal of 
the plug 31 from the tricoupler 30 because of the engagement of the 
vertical surfaces 76--76 of the tab 70 with the vertical surfaces 117--117 
which define the openings 113--113. 
The ease with which plugs 31--31 may be inserted into and removed from the 
modular tricoupler 30 facilitates residential and commercial wiring and 
interconnection of customer station equipment to the network. The free end 
of the tab 70 of the plug 31 extends beyond end surfaces of the plug to 
permit its digital depression by a customer so that it reassumes the 
arched configuration of entry. The cavity 83 is formed so that with the 
plug body 51 in proximate engagement with the ceiling 105 and the ledges 
103--103, the depression of the tab 70 moves the shoulders 75--75 a 
distance so that the flats 78--78 are disposed substantially at the level 
of the ledges 111--111 to permit withdrawal of the plug. 
Each of the wire-like contact elements 90--90 includes end portions 121 and 
122 (again see FIG. 4). The retroflexed end portion 121 is received in the 
cavity 83 of the two generally opposed cavities, and the other end portion 
122, in the third cavity 87. The end portions 121 and 122 are disposed in 
the plug-receiving cavities in a manner such that they are adapted to 
engage portions of the blade-like terminals 60--60 of modular plugs 31--31 
that are inserted into those cavities. Each contact element 90 includes a 
portion 124 which extends through a passageway 125 between an upper 
portion 126 and one of the plurality of separators 97--97. Each passageway 
125 is designed so that a radiused portion 128 of the contact element 
associated therewith avoids engagement with an adjacent corner 129 of the 
housing 80. 
Each contact element 90 includes a hoop 131 which shifts when a portion of 
it is engaged by a terminal 60. By allowing the loop 131 to flex in a 
relatively short distance between cavities, a permanent set of the 
wire-like contact element 90 is avoided. The loop 131 of each contact 
element 90 make a turn about one of the separators 97--97 position between 
two partitions 96--96 or between a partition and wall of the housing 80. 
As it makes its turn, it engages and is supported by a corner portion 136 
of the separator which spaces apart the partitions 96--96 that form the 
compartment in which it is positioned. As can be observed from the 
drawings, an opposite corner 137 of the separator 97 is not engaged by the 
contact element 90 in its turn. 
Following on from the vicinity of the corner 137, the loop 131 extends 
toward the center of the tricoupler 30. Each contact element 90 is 
unsupported as it dips downwardly into a chamber 141 disposed below a 
portion 142 of the jack cavity 87. From there, each contact element 90 
extends angularly upwardly past, but spaced from, the associated portion 
142. Adjacent to the portion 142, the contact element 90 turns at a corner 
146 and includes a portion 147 that extends through a passageway 148. At 
the end of the horizontal portion 147, the contact element 90 includes a 
radiused portion 149 that connects with the retroflexed end portion 121. 
When a modular plug is inserted into the cavity 82, each terminal blade 60 
engages a contact element 90 along a portion 143 of the loop 131. As the 
plug 31 is moved to its fully inserted position, the loop 131 is shifted 
to a position where it is spaced from the corner 136 and an opposite 
corner 137 of the associated separator 97. If that modular plug 31 is 
withdrawn from the cavity 82, the loop 131 of the contact element 90 has 
sufficient resiliency so that it shifts and returns to its original 
position. Also, the loop 131 is moved without any significant resulting 
movement in the end portions 121 and 122 which would adversely affect the 
electrical contact pressure between the contact element 90 and the 
terminals 60--60 of inserted plugs 31--31. 
In FIG. 1, there is shown the wall outlet 20 for providing in-wall 
telephone service between inside wiring 33--33 terminated with modular 
plugs 31--31 and customer station equipment. As will be recalled, wall 
outlet 20 includes the receptacle 23 which houses a tricoupler 30. The 
tricoupler 30 is capable of being received in any number of in-wall 
receptacles. As an example, the receptacle 23 includes a portion 154 
having sidewalls 156--156, a base 157, and an open side 158. A flange 159 
extends outwardly from the sidewalls 156--156 and is used to mount the 
receptacle 23 to a supporting member 161 within a wall of a customer's 
premises. 
The tricoupler 30 is adapted to be secured to the cover 25 which is mounted 
to the receptacle 23 such that the third cavity 87 faces outwardly and is 
exposed through an opening 162 in the cover. Both the receptacle 23 and 
the cover 25 preferably are made from a rigid dielectric material which is 
easily molded. This arrangement differs from the conventional wall outlet 
in which inside wiring is connected to a connecting device inside the 
receptacle with a jack in the cover plate being connected by wires to the 
device inside the receptacle. 
Initially, the cover for the wall outlet 20 appeared as is shown in FIG. 5. 
That cover, which is designated by the numeral 160, was also adapted to 
have the tricoupler 30 secured thereto and in turn to be secured to the 
receptacle 23 (see FIG. 6). As seen, the tricoupler 30 is formed with a 
groove 163 on each of two opposing sides of the housing 80. These grooves 
163--163 are adapted to receive latching tabs 164--164 which depend from 
the cover 160 that is adapted to enclose the receptacle 23 in much the 
same way that a cover plate covers the well-known electrical outlet for 
home or business use. 
Going now to FIG. 7, it can be seen that each of the latching tabs 164--164 
includes an end portion 167 having a latch 168 which is adapted to engage 
an end wall or keeper 169 of the groove 163 in the side of the tricoupler 
30. The length of the grooves 163--163 from the base 92 toward the cavity 
87 is such that when the cover 25 is positioned over the housing 80, the 
latches 168--168 are adapted to engage the keepers 169--169. The latch 168 
and the end wall 169 are configured to provide a generally right angle 
corner along the surfaces which engage each other. The keeper 169 of each 
groove of the tricoupler housing 80 is always at right angles to adjoining 
surfaces of the housing as is shown in FIG. 7. By this arrangement, the 
cover is adapted to be secured to the tricoupler 30 to the extent that the 
cover must be removed from the receptacle 23 and substantial forces 
applied to remove the cover from the tricoupler. This prevents inadvertent 
dislocation of the tricoupler 30 from the cover when a customer inserts a 
plug 31 into the cavity 87. As can be seen by referring to FIG. 1, the 
above-described latching arrangement is also included in the cover 25. 
As can be imagined from a perusal of the cover 160 of FIG. 5, a customer or 
a craftsperson might not successfully align the latching tabs 164--164 of 
the cover 160 with the grooves 163--163 at first try. Should a latching 
tab 164 be inserted inadvertently into the cavity 87, it could deform and 
undesirably reposition one or more of the end portions 122--122 of the 
contact elements 90--90. 
In order to overcome this problem, the cover 160 of FIG. 5 is modified to 
include alignment facilities which are incorporated into the cover 25 of 
FIG. 1. The preferred embodiment of the cover 25 includes alignment means 
such as an alignment fence 171 (see FIGS. 1, 8 and 9) to assure that the 
latching tabs 164--164 are received in the grooves 163--163 of the housing 
80. This also insures that the opening 162 in the cover 25 becomes aligned 
with the cavity 87 of the tricoupler. The alignment fence 171 includes two 
end portions 172--172 and two side portions 173--173 which cooperate to 
form a perimetral wall depending from the cover 25. Openings 176--176 are 
provided in the side portions 173--173 to provide for the latching tabs 
164--164. The end portions 172--172 and the side portions 173--173 are 
spaced so that when the cover 25 is mounted to the tricoupler 30, the end 
portions and side portions engage the ends 84 and 86 and the side walls 93 
and 94 of the housing 80 of the tricoupler. 
It should be appreciated that the portions of the alignment fence 171 
extend farther from the cover 25 than do the latching tabs 163--163 (see 
FIG. 9). In this way, the alignment fence encloses the tricoupler housing 
80 prior to the engagement of the latching tabs with the keepers 169--169. 
Reference to FIG. 1 is helpful in order to appreciate the technique for the 
assembly of the wall outlet. It will be observed that the inside wiring 
33--33 terminated with modular plugs 31--31 extends into the receptacle 23 
which is secured to a supporting member 161. A modular tricoupler 30 is 
secured to a cover plate 25 by causing the latching tabs 164--164 to be 
received in the grooves 163--163 of the tricoupler housing 80. The 
alignment fence 171 insures that neither tab 164 is inserted into the 
cavity 87. Then the cover plate 25 with the tricoupler 30 secured thereto 
is mounted to the receptable 23 by turning fasteners (not shown) through 
holes 178--178 in the cover plate into sockets 179--179 in the receptacle. 
The sockets 179--179 in the receptacle 23 are molded therein in a manner 
to avoid any conflict with the lugs 85--85 formed on the housing 80. 
Should it be desired to disengage the cover 25 from the tricoupler 30, the 
customer need only remove the cover from the receptacle 23 to provide 
access to the latching tabs 164--164. 
In FIG. 10, the tricoupler 30, having opposed cavities 82 and 83 and a 
front entry cavity 87 for receiving a modular plug 31 that is connected to 
a line cord 32 extending to customer station equipment, is mounted on a 
baseboard 184. As shown, the tricoupler 30 is adapted to be secured to the 
baseboard 184 by the lugs 85--85 and to be enclosed with a cover 200. 
Also, the tricoupler 30 includes the side grooves 163--163 for receiving 
latching tabs which depend from the cover 200. The cover 200 has 
appropriate openings at each end and along a front to facilitate entry of 
plugs 31--31 that are connected to service cables 199--199 and a cord 32 
connected to customer station equipment. However, as can be imagined, a 
customer or an installer inadvertently could cause a latching tab to enter 
the cavity 87. 
A preferred embodiment of a cover 200 for the tricoupler 30 of FIG. 10 
which is attached to an external surface of a wall is shown in FIGS. 
11--13. The cover 200 includes a top 201, two sides 203--203 an open side 
204 and two ends 205--205. Each of the ends 205--205 is formed with a 
slotted opening 206 through which a service wire 199 (see FIG. 10) extends 
to a modular plug 31 that is received in one of the opposed end cavities 
of the tricoupler. Portions of the sides 203--203 are formed with 
striations 208--208 to provide gripping surfaces for a user who wishes to 
install or to remove the cover 200. The top 201 includes an opening 209 
which provides customer access to the tricoupler cavity 87. 
As can best be seen in FIGS. 11 and 12, the cover 200 also includes a pair 
of latching tabs 211--211 which project from the top 201 toward the open 
side 204. The latching tabs 211--211 are adapted to snap-lock into the 
grooves 163--163 (see FIG. 10) on the sides of the tricoupler 30 when the 
cover is positioned over the tricoupler. Unlike the arrangement which is 
shown in FIG. 1, the latching tabs 211--211 of the cover 200 of the 
baseboard-mounted tricoupler 30 are modified to avoid a right angle 
surface for the latches 168--168. Rather, each latch 168 is sloped 
somewhat (see FIG. 11) to reduce the force that must be applied to remove 
the cover from the housing 80. Substantial forces are not required to 
remove the cover from the housing 80 of the baseboard mounted tricoupler 
30 inasmuch as there is little danger of dislodging the tricoupler from 
the cover because the tricoupler is secured to the baseboard 184. 
Advantageously, the cover 200 includes guide provisions for insuring that 
the latching tabs 211--211 are received in the grooves 163--163 on the 
sides of the tricoupler 30 and not inadvertently moved into the cavity 87 
of the front facing jack cavity. These provisions include an alignment 
fence 214 (see FIG. 12) comprising two side portiions 216--216 and two end 
portions 218--218. Each of the side portions 216--216 is interrupted by an 
opening 219 to accommodate a latching tab 211. 
The guide provisions also include a plurality of camming wedges spaced 
about the alignment fence 214 and extending between the alignment fence 
and the sides and ends of the cover 200. Two wedges 221--221 are formed at 
each end of the alignment fence, two wedges 223 and 224 on one side and 
two, 226, 228 on the other side of the fence. Each of the wedges slopes 
from an exterior wall of the cover 200 to the alignment fence (see FIGS. 
11 and 13). Should the fence 214 not be aligned with the tricoupler 30 as 
the cover 200 is positioned over the tricoupler, the wedges engage 
portions of the tricoupler and cam the cover into its aligned position. 
This action may be enhanced by continuing the slope of the camming wedges 
across the sides and ends of the alignment fence 214, as is shown in FIG. 
13. 
As was mentioned, the camming wedges slope toward the alignment fence 
thereby decreasing the distance between opposing wedges. This arrangement 
is effective to provide a converging guide to funnel the cover over the 
tricoupler 30 and cause it to become centered over the tricoupler. 
It should be observed from FIG. 12 that the side wedges 223,224 are offset 
from the side wedges 226,228. This is done in order to avoid engagement of 
the wedges with the mounting lugs 85--85 of the housing 80. Viewing now 
FIGS. 11 and 12, it should be appreciated that as the cover 200 is 
positioned over the tricoupler 30, one lug 85 is received in a portion 227 
of the cover defined between an end wedge 221 and the wedge 226. The other 
lug 85 is received in a space 229 between an end wedge 221 and the side 
wedge 224. 
It is to be understood that the above-described arrangements are simply 
illustrative of the invention. Other arrangements may be devised by those 
skilled in the art which will embody the principles of the invention and 
fall within the spirit and scope thereof.