Abstract:
An improved cover is provided for a remote terminal base, the new cover defining an interior cavity having means for mounting a 400-series card electronic card-module therein. The improved cover may replace a standard flat cover on the remote terminal base to facilitate the implementation of a 400-series card module. The interior cavity of the improved cover is deep enough to accommodate the card module and has a hinged intermediate door to which the card module is mounted. When the door is opened, card guides on the door slidably receive the card module. The door is then closable to sealably encase the card module within the cover.

Description:
FIELD OF THE INVENTION 
     The present invention generally relates to a telephone service remote terminal and more particularly to a cover for a remote terminal which facilitates the mounting and enclosure of an additional circuit module. 
     BACKGROUND OF THE INVENTION 
     Demand for telecommunication service has greatly increased in recent years in response to the use of telephone lines for a variety of digital and analog voice, data and video applications. Such line demand promises only to increase with growing communication needs such as the Internet. 
     Communication companies have an embedded infrastructure containing only a fixed number of lines connecting to customers. Therefore, in order to avoid installing additional wiring lines to keep up with growing user demand, various multiplexing techniques have been developed which permit the transmission of several channels over each line. The increase of transmission capacity over existing lines has been a major focus of telecommunications developments. 
     In user environments involving numerous customer lines, such as commercial office buildings or apartment buildings, multiplexing circuitry has been used to convert each subscriber line signal into multiple user signals. For example, one currently popular multiplexing technology is known as digital dual-line (“DDL”) (one in/two out). DDL circuitry essentially enables one subscriber line to carry the signals of two telephone customer lines. This advantageously increases the number of circuits for the same number of lines. 
     The enhanced electronic circuitry to carry out DDL multiplexing may be contained within a standard-configuration circuitry module known as a 400-series card module. In addition to packaging DDL circuitry, card modules are widely used to package circuitry for various other technologies as well, such as HDSL (“high density subscriber line”), ADSL (“asynchronous digital subscriber line”), RDSU (“rapid download/slow upload”), and ISDN (“integrated services digital network”) circuitry. In all of these applications, the standard card module facilitates a convenient “plug-in” installation of the electronics. 
     While card modules have been used to implement advanced transmission techniques in high-density telecommunication environments, such modules have not been used in applications having relatively few user lines, such as individual houses. Instead, each of these locations is usually provided with at least one wall-mounted box known as a remote terminal (known in the industry as an “RT”) which houses a connection interface between a main telephone company line and each individual user line. 
     In an increasing trend, occupants of houses and apartments are installing additional user lines for computer modems, fax machines, or simply for additional personal or business telephone lines at home. This installation of new user lines conventionally requires the routing of corresponding additional subscriber lines into a remote terminal. Unfortunately, there has been no practical means to date for implementing advanced electronics at an individual customer site to avoid the increasing number of relatively bulky remote terminals. 
     In order to provide upgraded modern service to customers having standard remote terminals, it is desirable to implement within a remote terminal the type of modern telecommunications electronics provided in card modules. To do so would also reduce the number of subscriber lines routed into a multiple-user remote terminal, because the upgraded circuitry could multiplex a single subscriber line into multiple user lines. Unfortunately, an existing remote terminal unit does not have enough internal space to mount a standard card module, and redesigning a completely new remote terminal base to permit the mounting of a card module adjacent to the existing base-mounted connector components would be impractical because many standard remote terminals are in use, and complete replacement of each unit would involve tremendous resources for their manufacture and reinstallation at each facility. Accordingly, a need exists for a means to adapt conventional remote terminal wiring for use with upgraded circuitry in a manner which maximizes the utilization of a conventional remote terminal structure. 
     SUMMARY OF THE INVENTION 
     A primary object of the invention is to provide a remote terminal capable of housing advanced electronic circuitry. 
     Another object of the invention is to adapt existing remote terminal equipment for upgraded operation with modem electronic telecommunication circuitry. 
     A related object is to provide a means for mounting such circuitry with existing remote terminal structure. 
     In accordance with the invention, a remote terminal is provided for receiving a standard circuitry module for manipulating a signal. The remote terminal includes an improved cover which can also be substituted for a conventional cover on a standard remote terminal. The improved cover of the invention has an enlarged interior capacity for accommodating the installation of a circuitry module to operate in conjunction with existing components conventionally mounted in the base. Preferably, the improved cover is adapted to connectably receive a standard-sized card module. 
     An advantage of the invention is that the cover may be used with an existing remote terminal base to upgrade the electronic circuitry without completely replacing the entire existing remote terminal structure. 
     These and other features and advantages of the invention are described in, and will be apparent from, the detailed description of the preferred embodiments and from the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of an eight-line remote terminal having an improved cover according to an embodiment of the invention showing the door open relative to the cover to provide access to the circuit cavity. 
     FIG. 2 is an exploded perspective view of an eight-line remote terminal base constructed in accordance with teachings of the invention. 
     FIG. 3 is a perspective view of the remote terminal of FIG. 2, showing the door in a closed position in the improved cover. 
     FIG. 4 is a perspective view of a cover according to an alternative embodiment of the invention wherein the hinge includes pins which extend through the cover body and engage into complementary bores in the door. 
     FIG. 5 is a perspective view of an improved cover including a locking element to hold the card in an inserted position and a light pipe element mounted to the door. 
     FIG. 6 is an enlarged view of a corner of the door of FIG. 5 showing the locking element in greater detail. 
     FIG. 7 is a fragmentary side view of the corner of the door of FIG. 6, showing the locking element in a closed position. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to the figures, wherein like numerals designate like parts, an eight-line remote terminal  30  having an improved cover  32  according to an embodiment of the invention is illustrated in FIG.  1 . 
     As shown in FIGS. 1 and 2, the remote terminal  30  has a wall-mountable base  12  including a base body  13 . The base body  13  is generally shaped like an open-sided box in which equipment is mounted for connecting an individual subscriber line to a particular user line. Traditionally, the left side of the base  12  contains wiring which is in the domain of the telephone company. The right side of the base  12  typically houses individual user lines which are traditionally in the user&#39;s domain. Equipment connected from the right side is known as CPE, or “customer premises equipment”. The right side wiring is connected to the left side at a central region known as a point of demarcation. 
     The base  12  receives a subscriber line through a port  16  at a lower left side of the base for connection with a terminal (not shown). At the left side of the base  12 , a telephone company cover  18  may be provided to prevent tampering with the telephone company connections. The right side of the base  12  contains a plurality of screw terminals  20  provided to connect individual customer lines. The individual customer lines run from the screw terminals  20  through a port  22  at a lower right side of the base  12  for connection to individual users at a remote location such as, for example, individual apartments in an apartment building. 
     According to one aspect of the invention, an improved cover is provided which mount to the base while maintaining hingability. Because the cover is preferably designed to replace a conventional flat cover for a remote terminal, the cover  32  has appropriately designed dimensions and hinge fittings  34  to facilitate the substitution for a particular standard flat cover. It will be appreciated that, although the new base  12  preferably is designed to match the conventional closure dimensions, the cover  32  and base  12  could be cooperatively dimensioned otherwise. The improved cover  32  has a box-like shape which is larger than a conventional cover  14  and defines an interior for receiving a circuit module, as described below. Particularly, the cover  14  is adapted to house a card module  40  such as a 400-Series electronics card module for multiplexed network interfacing. 
     The one open side matably closes against the base. According to a preferred embodiment, the cover  32  has a door  38  which may be pivoted between open and closed positions to seal the interior of the body  36  at approximately mid-depth. In the open position, the door  38  projects outwardly from the interior, as shown in FIG. 4, to slidably receive the card module  40 . In the closed position, the door  38  separates the interior of the cover between a base-receiving recess  42  and a sealable circuit cavity  44 . The card module  40  is housed within the circuit cavity  44 . 
     A pair of hinges  46  are provided to pivotally mount the door  38  to the body  36 . The hinges  46  are mounted at opposite sides of the door  38 . As shown in FIG. 4, each hinge  46  includes a pin  50  which extends through a bore  52  in the body  36  and snap-fits into the door  38  so that ends of the pins  50  rotatably reside in the cooperating bores  52  in the body  36 . Via the hinges  46 , the door  38  may be pivoted open to provide access to the circuit cavity. As will be appreciated by those skilled in the art, the door  38  can be hingably mounted to the cover body  36  by other appropriate means as well. For example, in the embodiment of FIG. 3, hinges  46 ′ according to an alternative construction are provided at opposite sides of the door  38 , each hinge  46 ′ including an outwardly-extending peg (not shown) for respectively engaging the bores in the body  36 . 
     In FIG. 1 which shows the door  38  in an open position, means is shown for mounting the card module  40 . A pair of parallel card guides  54  are mounted on opposing sides of the door  38  facing the circuit cavity  44 . An elongated slot  56  is formed in each of the card guides  54  for receiving a lip  58  which protrudes from the card module  40 . At an end of the door  38  near the hinges  46 , a connector block  60  is provided for matably receiving a male connector portion of the card module  48  in a pluggable manner to form an electrical connection. When the door  38  is opened to provide access to the circuit cavity  44 , the card module  40  can easily be installed by slidably inserting the card module  40  between the card guides  54  until the card module  40  electrically mates with the connector block  60 . 
     As illustrated in FIGS. 5,  6  and  7 , a locking element  70  is preferably provided for retaining the installed card module  40  securely between the card guides  54  and engaged with the connector block  60  in an installed position. In the illustrated embodiment, the locking element  70  is L-shaped, having a projecting clamp  71 . Furthermore, the locking element is mounted to the door  38  by a threaded screw  72  for rotation between open and closed positions. In the open position shown in FIG. 6, the clamp  71  is disposed outwardly of the module  40  so that the module may be slidably inserted/retracted into the slots. In the closed position, the clamp  71  is disposed inboard of the module  40  to prevent inadvertent retraction of the module  40  from the door  38 . As shown in FIG. 7, a screw  72  extends through an oblong hole  73  in the locking element  70  to permit slidable adjustment of the locking element relative to the door  38 . The locking element  70  also includes a small tab  74  which slides in a channel  76  disposed in the door  38  parallel to the card guides  54  to linearly guide the locking element  70  for adjustment within the range d permitted by the oblong hole  73 . As shown in FIGS. 5 and 6, the locking element  70  is shown in a non-locking position. In the closed position shown in FIG. 7, the tab  74  aligns with the channel  76  and guides the locking element  70  to securely abut against the module  40 . 
     Also, to facilitate convenient access to the circuit cavity  44  for insertion, repair or removal of a card module, the cover  32  may include a catch member (not shown) which selectively holds the door in an open position. 
     As shown in FIGS. 1,  4  and  5 , the cover body  36  has a shoulder  80  disposed about a periphery of the interior walls, which the door  38  abuts against in a closed position. Preferably, the shoulder  80  has a peripheral groove  82  which can be filled with a sealant, such as an epoxy resin, to create a water-tight seal between the body  36  and the door  38  when closed. Accordingly, the door  38  can include a rib  84  (also shown in FIG. 6) positioned near a peripheral edge of the door  38  to matably engage the groove  82  when the door  38  is closed. The rib  84  provides a good gripping surface for the cured sealant. Additionally, the cover  32  may include screws  86  as illustrated in FIGS. 4,  5 , and  6 , which extend through the door  38  and to the shoulder  80  for threadable tightening of the door  38  in the closed position. 
     A flexible cable  88  (FIG. 3) is provided to provide electrical communication between the module  40  and the base  12 . In particular, the cable  88  carries an appropriate electrical signal to and from the card module  40 , passes through an opening  90  (see FIG. 4) in the door  38  and is connected to the connector block  60  for communication with the card module  40 . The cable  88  has a sufficient amount of slack to not interfere with the opening and closing of the cover  32  on the base  12 . The door  38  includes a cable cap  92  (see FIGS. 3 and 4) forming an enclosed channel through which the cable passes. The cable cap  92  is removable to aid in manipulation of the cable  88  during installation. 
     Some card modules  40  may have one or more LED indicator  94  which indicate the operation of a certain function by the card module. When the door  38  is closed on the cover body  36 , enclosing the card module  40  in the circuit cavity  44 , the module  44  and associated LEDs  94  are not directly visible by a repair person. As illustrated in FIG. 5, to permit viewability of these optic indicators  94  while the door  38  is closed, on the body  36 , an optional light pipe element  96  may be mounted to the door to provide optical communication through the door  38 . The light pipe element  96  is essentially a translucent optic guide which may be made of molded plastic. In the illustrated embodiment, the light pipe element  96  includes three elbow-shaped light channels  98 . As shown, each of these light channels  98  has a first end which is viewably positioned in a view opening in the door  38  and a second end which is positioned proximally to a corresponding one o the LED indicators on the card module  40 . The viewable first ends of the light pipe element  96  are illuminated when the optic indicators  94  on the card module  40  are active. 
     As will be understood by those in the industry, the card module  40  may have a push-button switch for actuating a particular circuit feature or operation. For example, a DDL card module may includes an enhanced provisioning function (“EPREP”) for use with a digital subscriber line. The push-button on the card module  40  must be pressed to turn off the EPREP function for certain repairs. 
     Accordingly, to permit actuation of the push-button while the door  38  is closed on the body  36 , a flexible membrane  100 , such as rubber or the like, as shown in FIG. 3, is preferably mounted in an opening of the door  38  at a position adjacent the button on the card module  40 . The presence of the membrane  100  avoids the need to open the door  38  to access the card module  40 , which may be difficult when a sealant has been applied between the shoulder  80  of the body  36  and the door  38 . 
     As shown in FIGS. 1,  2  and  3 , a plurality of tip and ring covers  120  are preferably provided to cover the respective screw terminals  20  for each user line. The tip and ring cover  120  permits the respective user to restrict access to his respective telecom connections. Each of the tip and ring covers  120  is pivotable between an open and closed position via a snap-fit hinge  122  formed at a right side thereof. The hinge  122  engages a cooperating channel  124  formed in the base body  13 . Each of the tip and ring covers  120  is latchable in the closed position by means of a tab  126  which flexes on a living hinge  128 . More particularly, when the tip and ring cover  120  is pivoted downwardly to the closed position, a projecting ridge  130  on the tab  126  snaps under an undercut edge  134  of the telephone company cover  18 , securely fixing the tip and ring cover  120  over the respective screw terminals  20  as well as an associated jack  132 . 
     Furthermore, the latched tip and ring cover  120  is lockable to prevent unauthorized access when the telephone company cover  18  is closed. For locking the tip and ring cover  120 , the tab  126  has an embossment  131  which receives a portion of an appropriately sized lock  133  (such as for example a No. 10 pedlock), preventing inward movement of the tab  126  which releases the ridge  130  from locking engagement of the undercut edge  134 . Advantageously, telephone company personnel can access all of the user connections even when one or more of the tip and ring covers  120  are locked, since all of the tabs  126  are released when the telephone company cover  18  is opened. 
     While the invention will be described in connection with certain preferred embodiments, there is no intent to limit it to those embodiments. On the contrary, it is recognized that various changes and modifications to the exemplary embodiments described herein will be apparent to those skilled in the art, and that such changes and modifications may be made without departing from the spirit and scope of the present invention. For example, the cover  32  could be designed to receive circuits other than the 400 series card module. Additionally, those skilled in the art will appreciate that the cover made in accordance with the invention can be used to install circuitry for a variety of applications to provide desired communication channels in both analog and digital environments for voice, data and fax applications. Additionally, the cover of the invention could be used to connect an electronics card module on either the telephone company side or the customer side of the point of demarcation. Therefore, the intent is to cover all alternatives, modifications, and equivalents included within the spirit and scope of the invention as defined by the appended claims.