Telecommunications equipment

A telecommunications shelf module is provided having electronic circuit packs and conductors extending from the circuit packs to an interface station for connection to conductors exterior of the pack, the module detachably mountable in a frame. The module preferably has a cooling arrangement included in its structure.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to telecommunications equipment. 
2. Prior Art 
In the telecommunications industry, telecommunications equipment is mounted 
in frames and is connected by signal conductors to other equipment mounted 
in other frames. Conventionally, components are mounted into shelves of 
such frames on site and circuit packs, when used, are fitted into the 
shelves. At the rear of the shelves, the circuit packs normally are 
connected to back planes and have connectors at their fronts from which 
the telecommunications conductors extend to other equipment items. The 
conductors necessarily extend across the fronts of the circuit packs and 
of the frames and the responsibility for their installation and of 
connecting them to the circuit packs is that of the installer. 
Installation of the conductors and their connection to the circuit packs 
is time consuming and tedious and, in view of this, together with the 
possibility of human error, interconnection mistakes are likely to occur. 
Such mistakes result in problem solving requirements which again is time 
consuming and tedious. 
SUMMARY OF THE INVENTION 
The present invention seeks to minimize or overcome the above problem. 
According to one aspect of the present invention a telecommunications 
equipment shelf module comprises a shelf provided with a plurality of 
receiving stations for electronic circuit packs, a plurality of electronic 
circuit packs received within the plurality of receiving stations, 
telecommunications conductors extending between and interconnecting the 
circuit packs with connectors mounted in a connector interface station of 
the module for connection to further telecommunications conductors 
extending exteriorly of the module, and means for detachably mounting the 
module in a frame. 
The shelf module according to the invention may be factory made as a unit 
and thus, quality control of the product is ensured. Because the signal 
conductors are provided in the module extending between the circuit packs 
and connectors in the connector interface station, then installation 
problems associated with the installer connecting the conductors directly 
to the circuit packs is avoided. In view of this, all that is required of 
the installer is to connect the further signal conductors from exterior 
equipment directly into the connectors at the connector interface station 
of the shelf module. As a result, quality control is maintained at a high 
standard while minimizing the mistakes which may be made during 
installation of equipment by an installer. In addition, the amount of time 
required on site in assembling telecommunications equipment is minimized 
with the use of the modular construction. 
With the above structure according to the invention, cooling means are 
preferably provided for the circuit packs and with circuit packs disposed 
side-by-side horizontally in one or two vertically displaced rows, this 
leads to ease of circulation of a cooling fluid because of the vertical 
flow channels, which are thus provided. It is also preferred to provide a 
connector holder at the connector interface station, the connector holder 
housing the connectors and being movable between a connector housed 
position within a housing of the module and a connector access position 
with the connector holder moved forwardly of the housing. With this 
preferred arrangement, the telecommunications conductors extending from 
the circuit packs are advantageously positioned so as to extend rearwardly 
into the housing from the fronts of the packs and to the connectors 
contained within the connector holder. In this way, with the pre-built 
shelf module, the conductors are easily directed from the fronts of the 
circuit packs to the connector interface station for connection to other 
conductors extending to other telecommunications equipment. Thus, in the 
finished assembly of the shelf module into a frame, conductors are 
eliminated or virtually eliminated at the fronts of the circuit packs and 
of the frame. Further, in a preferred arrangement, the connector holder is 
pivotally connected at a front region of the housing of the module for 
pivotal movement between the connector housed and connector access 
positions. In this case, the conductors extending rearwardly into the 
housing may be required to extend outwardly from a side of the housing in 
one location and then inwardly into the side of the housing in another 
location so as to lie close to the pivotal axis of the connector holder as 
they extend to the connectors. With this arrangement, pivotal movement of 
the connector holder between its two positions requires an insignificant 
change in length of the conductors extending into the compartment, because 
the distance between the incoming conductors as they lie close to the 
pivotal axis and the connectors remains virtually the same. Thus, movement 
of the conductors lengthwise relative to the housing which could result in 
abrasion of conductors is avoided. 
According to a further aspect of the present invention, telecommunications 
equipment is provided comprising a frame having a plurality of bays for 
detachably receiving telecommunications equipment shelf modules, at least 
one of the modules comprising a shelf provided with a plurality of 
receiving stations for electronic circuit packs, a plurality of electronic 
circuit packs received within the plurality of receiving stations, 
telecommunications conductors extending between and interconnecting the 
electronic circuit packs with connectors mounted in a connector interface 
station of the housing for connection to further telecommunications 
conductors extending exteriorly of the module, and the frame and the at 
least one shelf module having cooperable means for detachably holding the 
module in one of the bays. 
The invention also includes telecommunications equipment comprising a 
housing, a connector holder for holding connectors for telecommunications 
conductors, the connector holder pivotally mounted to the housing and 
pivotally movable between a connector housed position with the connector 
holder within the housing and a connector access position with the 
connector holder pivoted forwardly of the housing, the connector holder 
having spaced apart connector mounting positions in at least one arc 
around the pivotal axis of the connector holder. 
With the telecommunications equipment according to the invention in the 
last preceding paragraph, the connector holder structure and location of 
the connector mounting positions is such as to allow for compactness and 
density of connectors. It has been found that with connectors disposed in 
an arc as in constructions according to the invention and around the 
pivotal axis of the connector holder, then this allows for ease of 
connection of the conductors to the connectors. In addition, the 
conductors may be caused to extend radially inwards from the connectors 
towards the pivotal axis so as to emerge from the connector holder in a 
position adjacent to the pivotal axis, and virtually no change in length 
of conductors is required during pivotal movement of the connector holder. 
In essence therefore, the connector mounting positions are disposed in an 
array around the arc extending around the pivotal axis and result in the 
conductor positioning being neat and closely controlled. 
In a preferred arrangement, the connector mounting positions are disposed 
in a plurality of arcs extending around the pivotal axis, one arc inside 
another and with the mounting positions staggered around the pivotal axis 
from each arc to an adjacent arc. With this preferred arrangement, the 
compactness of the spacing of the connector mounting positions is 
increased. The staggering of positions is provided to enable conductors to 
extend towards the pivotal axis across the connector holder from mounting 
positions in an outer arc by passage between mounting positions in an 
inner arc or arcs.

DETAILED DESCRIPTION OF THE EMBODIMENT 
As shown in FIGS. 1 and 2, telecommunications equipment 10 comprises a 
stationary frame comprising vertical rear frame members 12 and front frame 
members 14 which are horizontally spaced apart by horizontal frame 
members, such as shown at 15 in FIG. 2, to provide a rigid structure. 
The equipment 10 has different items 16 of equipment in a left-hand bank as 
shown in FIG. 1. However, in the right-hand bank, and as shown 
particularly in FIG. 2, the frame is provided with a vertical stack of 
bays 18, namely three, for containing shelf modules 20 of equipment. Each 
shelf module 20 (one only being shown for description purposes) is 
slidably received within its appropriate bay 18 and for this purpose means 
is provided with means for detachably receiving and holding each of the 
modules in position. The receiving and holding means comprises, for each 
bay, horizontally spaced-apart guide and support rails 22 extending 
between frame members 12 and 14, bolt holes 24 in the frame members for 
reception of bolts (not shown) into aligned holes 26 in the module when 
disposed correctly within its appropriate bay. 
Each module 20 is of rectangular box-shape which, as shown by FIGS. 2 and 
4, is provided by an outside housing 28 having a rear wall 30, top and 
bottom walls 32 and 34 and side walls 36. Within the box are provided a 
plurality of receiving stations 38 for electronic circuit packs 40. The 
circuit packs 40 are arranged side-by-side horizontally in two rows, one 
above another, as shown particularly in FIGS. 3 and 4, with connectors 42 
at the rear ends of the packs connected into a back plane or planes 44 
which extend vertically at the rear of the receiving stations 38 in a 
spaced position from the rear wall 30 to provide a vertical space 46 
forwardly of the rear wall. The circuit packs 40 may be slidably inserted 
and withdrawn from the front of the module through a central opening 
provided in a front wall 48 of the housing. 
Cooling flow passage means is provided in each module. As shown in FIG. 4 
the cooling flow passage means comprises an inlet chamber 50 disposed 
below the circuit packs 40 and an outlet passage 52 disposed above the 
circuit packs. These two passages are interconnected by flow passages 
defined between adjacent circuit packs 40 in the receiving stations, the 
circuit packs having side walls which are slightly spaced-apart for this 
purpose. The inlet and outlet passages 50 and 52 are also interconnected 
by means of the chamber 46 defined between the back plane 44 and the rear 
wall 30. Thus, in use, there is circulation of cooling air by convection 
through the chamber 50 and upwardly into the chamber 52. The inlet passage 
50 receives its air through a louvered door 54 (see FIGS. 2, 3 and 4) 
which is pivotally hinged about a lower edge to enable it to be lowered 
into the position in FIG. 3 for any maintenance purposes. The outlet 
passage 52 exhausts air through a louvered panel 56 forming part of the 
front wall 48. 
The shelf module is provided with a connector interface station 58 which is 
disposed above the outlet passage 52. At the left-hand side of the station 
58 as viewed in FIGS. 2 and 3, there are provided tiered pivotal trays 60 
which are pivotally mounted in a manner not shown, for movement out of a 
stowed position, as shown in FIGS. 2 and 3 to a forward position for 
access purposes. These trays are optical fiber storage and connector 
trays. In the event that one or more of the circuit packs 40 is to be 
connected by optical fibers to outside equipment, i.e. away from the frame 
10, then optical fibers from this circuit pack or packs will extend to the 
trays 60 for storage purposes and for purposes of connecting these fibers 
into optical connectors, other ends of which are to be connected by an 
installer of the equipment to the outside equipment. 
Also provided in the connector interface station 58 is a connector holder 
62 (FIGS. 2, 3 and 4) which, as will now be described, is for receiving 
electrical conductor wires from the packs 40 in the event that the packs 
are to be serviced electrically. 
The connector holder 62 is shown in detail in FIGS. 5, 6, 7 and 8. In 
underside plan view as shown in FIGS. 5 and 8 and plan view in FIG. 6, the 
connector holder 62 is shaped as a quadrant of a circle, this shape being 
fundamentally provided by a base 64. The base has radial edge flanges 66 
and 68 and a part circular flange 70 at the arcuate edge of the base. 
Holder 62 is mounted in the housing of the module so as to be movable 
outwardly from a stowed position within the housing to a position 
extending outwardly from the front of the housing for access to the 
connectors for installation and maintenance purposes. For this purpose, 
the holder is pivotally mounted at the front of the housing about a 
pivotal position 72 which coincides with the center of the circle of which 
the base 64 forms a quadrant. FIGS. 1, 4 and 5 show the connector holder 
in the stowed position while FIGS. 6 and 8 show it in the outer connector 
access position. 
Telecommunications connectors 74 are mounted to the base 64 in such a 
manner as to provide compactness and maximization of density of the 
connectors. This object is achieved by disposing the connector mounting 
positions in spaced-apart locations around at least one arc which is 
centered upon the pivotal axis of the connector holder. Preferably, and as 
shown in the embodiment, there is more than one arc of connector mounting 
positions. In the embodiment, two connector mounting position arcs 75 and 
76 are shown and the connectors are mounted around these two arcs with the 
connector mounting positions staggered from one arc to the other along the 
arcs. Electrical conductors 78 extend from connectors 80 at the fronts of 
the circuit packs 40 and extend slightly forwardly of the packs before 
extending downwardly and then rearwardly for a distance behind the circuit 
packs before progressing upwardly of the module 20 through gaps and 
passages provided within the module. These conductors 78 then proceed 
through an aperture 84 towards the upper front of the housing wall 36, the 
conductors being arcuately bent on the outside of the housing side to 
re-enter the housing through an upper aperture 86. The aperture 86 directs 
the conductors, as shown in FIGS. 5 and 8, towards the underside of the 
base 64 of the connector holder and in such a position that as the 
conductors extend towards their respective connectors 74, they pass 
closely adjacent to the pivotal axis 72. The conductors therefore move 
basically radially from the pivotal axis 72 to their respective 
connectors. As may be seen, the conductors extending to the connectors in 
the outer arc 75 pass easily between the conductors on the inner arc 76 
because of the staggered relationship of the connectors in the two rows. 
The relative positioning of the connectors on each arc and between 
connectors in the arc 76 on the base 64 allow for compactness of the 
connectors with a high density upon the base 64 while enabling for ease of 
distribution of the conductors to their respective connectors. As may be 
seen particularly from FIGS. 5 and 8, the conductors enter the aperture 86 
in bunched form, and then diverge from one another to their respective 
connectors in an orderly fashion which assists in installation and removal 
of the conductors as and when necessary. 
As may be seen from the above description, the shelf module is factory 
built whereby a standard of assembly may be achieved by the manufacturer. 
Included in this is the fact that the circuit packs are each individually 
connected by the manufacturer to the connectors in the connector holder 62 
and sufficient care is made possible by the manufacturer to connect the 
appropriate terminals of the circuit packs to the appropriate connectors. 
Together with this is the fact that the signal conductors 78 are pre-built 
into the module before final installation into the frame of the equipment 
and this enables the conductors to be bypassed from the front of the 
module, i.e. rearwardly into the module itself and to the connectors in 
the connector holder, whereby the finished assembly provides a clean 
frontal appearance with little or no conductors being apparent an than 
location. Such an arrangement with conductors being obscured from the 
front of the equipment would not be possible if the assembly of the parts 
were to be made in situ in the frame as according no conventional practice 
and in which the conductors extend exteriorly from the circuit packs 
directly to other telecommunications equipment. In this embodiment, 
however, as specified the conductors are not apparent from the front of 
the module in the finished equipment. Thus the module is completely 
controlled in its manufacture and may be tested exhaustively before being 
sent to the installer for connection to other telecommunications 
equipment. 
Upon being received by the installer, it is simply necessary for him to 
dispose each module 20 in its respective bay 18 and secure it in position 
by the means described above. Incoming telecommunications conductors are 
then brought from outside telecommunications equipment and connected 
either to optical connectors in the trays 60 or to the connectors 74 in 
connector holder 62. Where conductors are brought to the connector holder 
62, these are in the form of insulated conductor wires 88 which extend 
downwardly at one side of the frame adjacent to the position to be 
occupied by the sides 36 of the modules 20 having the apertures 84 and 86. 
The positions of such conductors are shown in FIGS. 1 and 2. When a module 
20 has been disposed into its correct location in its bay 18, it is simply 
necessary for the installer then to insert the corresponding conductors 88 
through the aperture 86 in the side 36 of the module 20 and extend these 
conductors 88 across the top surface of the base 64 for instance as shown 
by FIG. 6. These conductors extend through the aperture 86 as a bunch of 
connectors and then diverge to their respective connectors in a manner 
similar to the positioning of the conductors 78 beneath the base 64. Thus, 
the conductors 88 also diverge from the aperture 86 as they proceed 
radially of the pivot position 72. The conductors 88 are easily connected 
to the connectors by disposing the connector holder 62 in its connector 
access position forwardly of the frame and as shown in FIG. 6. When the 
conductors 88 are correctly connected to the module 20, then the connector 
holder is pivoted rearwardly into its storage position and as shown by 
FIG. 5. As will be realized, movement between the storage and connector 
access positions (compare FIGS. 5 and 8) is accompanied mainly by a mere 
bending of the conductors 78 and 88 as they pass through the aperture 86 
to their respective connectors. Because the conductors extend mainly 
radially of the pivot position 72 then the movement of the connector 
holder 62 requires no significant change in length of the conductors 
between these two positions whereby conductors are not required to move to 
and fro excessively through the aperture 86. It follows therefore that the 
module structure of the invention and as described in the embodiment is 
for ease of quality control during manufacture while minimizing any 
chances of human error during installation in the field. Further to this, 
a factory built module enables conductors to be hidden from the front of 
the module whereas this would be impossible if the telecommunications 
equipment were built on site from their individual pieces of equipment. In 
addition, the connector holder is itself of unique construction and 
occupies a minimal space while allowing for a high density of mounting 
positions for the connectors.