A rack-mounted
assembly (10) comprises one or more racks, each capable of containing one or more printed circuit boards (PCB) (18), interconnected by a
backplane (15) which is located along the bottom of a shelf (14). This position of the
backplane (15) allows the rear wall of the rack-mounted
assembly to be perforated, thereby permitting a cooling
airflow for the PCBs to pass in through the front of the
assembly and then out through the back. An
insertion mechanism is provided to allow a PCB to be inserted into a rack. To achieve this, the PCB must first travel backwards into the rack-mounted assembly, and then downwards into engagement with the
backplane (15). In one embodiment, this is accomplished by supporting the PCB from a hanger (100) which moves in and out of the rack-mounted assembly along a guide rail (45). The hanger includes slots (115) that retain pins (110) from the PCB. The slots are orientated diagonally upwards and backwards. A compression spring (60) is also provided to urge the pins (and hence PCB) forwards. Upon
insertion, the hanger moves along guide rail (45) until the PCB abuts a stop (50). At this point further
insertion of the hanger forces the pins (110) to move along slots (115) in opposition to spring (60), thereby driving the PCB down into engagement with the backplane (15).