System and method for assembly of a processor and socket on an information handling system printed circuit board

A grid array socket pin field is protected during manufacture of an information handling system with a dust cap having first and second attachment devices. The first attachment device secures the cap to the socket during assembly of the socket in the computer. The second attachment device secures the cap to a load mechanism assemble proximate the socket. Engagement of the second attachment device to the cap automatically releases the cap from the socket to allow removal of the cap from the socket by actuation of the load mechanism to an open position. The second attachment device secures the cap to the load mechanism until a processor is placed in the socket.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates in general to the field of information handling system assembly, and more particularly to a system and method for assembly of a processor and socket on an information handling system printed circuit board.

2. Description of the Related Art

Improvements in the processing capabilities of information handling systems have resulted from greater processing capability of components used to build information handling systems, such as central processing units (CPUs). Improved processing capabilities have depended on improved information transfer speeds to communicate information between information handling system components, such as the use of serial links like those compliant with the PCI Express standard. One improvement that has helped increase information transfer speeds is the use of land grid array (LGA) sockets to interface a processing component, such as a CPU, with a printed circuit board (PCB), such as a motherboard. LGA sockets include a socket having a pin field disposed to align with pins exposed on the underside of a processing component, thus providing an increased surface area for pin connections compared with conventional sockets that have pins disposed around the periphery of the processing component. The socket pin field is an array of spring contacts that are deflected and provide a contact normal force between the CPU substrate via gold pads on the substrate and the gold plated spring contacts. Deflection with springs provides a minimum contact pressure for good contact to CPU circuitry with minimal resistance. The pin fields have an appearance of an array of slightly cantilevered lever springs. A load mechanism is secured to the printed circuit board over the top of the socket so that a load plate of the load mechanism closes down on an inserted processing component to maintain an interface between the socket pin field and the processing component pins.

One difficulty with the use of grid array sockets, such as LGA sockets, is that the pin field of the socket can suffer damage by even minimal contact with a foreign object or contaminant. During manufacture of an information handling system, manufacturers must exercise care to avoid damage to socket pin fields, especially between the time of attachment of the socket to the printed circuit board and securing of the processor in the socket by a load plate of a load mechanism. To help avoid inadvertent damage to the grid array pin field, the socket is typically covered with a dust cap that is engaged over the grid array pin field immediately after manufacture of the socket. One recently proposed LGA socket presents a challenge since the socket and grid array pin field are assembled to the printed circuit board followed by the load mechanism, which is assembled around the periphery of the socket. After the load mechanism is assembled around the socket, the socket dust cap is removed, the processor is put into place, and the load mechanism is activated so that the load plate holds the processor in place. Inadvertent damage can occur to the socket pin field during removal of the dust cap, such as by dropping the dust cap on the pin field or dragging the dust cap across the pin field.

SUMMARY OF THE INVENTION

Therefore a need has arisen for a system and method which protects a grid array socket from damage during assembly of an information handling system.

In accordance with the present invention, a system and method are provided which substantially reduce the disadvantages and problems associated with previous methods and systems for protecting a grid array socket from damage during assembly of an information handling system. A cap covers the socket during manufacture of the information handling system. Once a load mechanism is assembled proximate the socket, the load mechanism interacts with the cap to release the cap from the socket and raise the cap away from the socket for installation of a processor in the socket.

More specifically, a grid array socket is assembled to a motherboard. A dust cap covers the pin field of the socket to prevent damage to the pin field. The cap couples to the socket by interaction of an attachment device of the cap and an attachment point at the socket. A load mechanism is assembled proximate the socket, the load mechanism designed to hold a processor in the socket. A load plate of the load mechanism is assembled in a closed position over the socket or assembled in an open position and then moved to a closed position over the socket. An attachment device of the cap couples to the load plate when the load plate is in the closed position to secure the cap to the load plate. Interaction of the load plate and the cap's load plate attachment device automatically releases the cap's socket attachment device so that the cap is free from the socket. For example, the attachment device is an arm having a socket attachment device at one end and a load plate attachment device at an opposing end. Closing the load plate over the cap flexes the arm at the load plate attachment device to translate a release force to the socket attachment device. Once the cap is coupled to the load plate, the load plate is actuated to an open position to lift the cap from the socket and expose the socket pin field for installation of a processor in the socket. The load plate holds the cap until after installation of the processor so that removal of the cap does not result in the cap falling onto the socket pin field to damage the socket since the socket pin field is covered by the processor.

The present invention provides a number of important technical advantages. One example of an important technical advantage is that a socket is protected by a dust cap until after assembly of the socket on a printed circuit board, and then the dust cap is removed from the socket with minimal risk of damage by actuation of the load plate. Installation attachment features incorporated with the dust cap makes removal of the dust cap automatic by actuation of the load plate to an open position for installation of the processor. Removing the dust cap by interaction with the load plate limits the risk of damage to the grid array pin field of the socket since rotation of the load plate provides a lifting motion to the dust cap without dragging of the dust cap across the pin field. Coupling the dust cap to the load mechanism until after the processor is installed limits the risk that the dust cap will fall onto the grid array pin field until the pin field is protected by the installed processor. The dust cap aids with pick and place manufacture of printed circuit boards. The dust cap is pre-assembled to the socket so that a robotic arm uses the dust cap as a mean of attachment, such as with a suction cup. After all components are assembled and soldered to the motherboard, the load plate is then assembled with the socket pin field protected throughout the assembly process.

DETAILED DESCRIPTION

Referring now toFIG. 1, a side perspective view depicts an information handling system10having a socket12coupled to a motherboard14, the socket covered with a dust cap16. Socket12is, for example, a Land Grid Array (LGA) socket or other type of socket that interacts with a processor through a grid array pin field. Socket12is coupled to motherboard14during manufacture of an information handling system to support communication between a processor inserted in the socket and other components coupled to the motherboard, such as RAM or a chipset. Cap16couples to socket12with a socket attachment device18, which interacts with a socket attachment point20. Cap16protects socket12during assembly of information handling system10, such as by covering a pin field of socket12. For example, a suction cup attaches to cap16so that a robotic arm can pick up socket12via cap16to place socket12at an appropriate location of motherboard14. Socket attachment device18is an arm extending downward from cap16towards socket12. Socket attachment device18has an opening that fits over socket attachment point20to hold cap16in place over socket12. A load mechanism attachment device22extends upward from cap16on the opposing end of the arm forming socket attachment device18. Load mechanism attachment device22is positioned to engage a load mechanism load plate that closes over socket12. Engagement of load plate by attachment device22automatically release socket attachment device18to allow removal of cap16for insertion of a processor in socket12. For example, cap16transfers from attachment to the socket to attachment to the load mechanism by designing the retention force of cap16to the socket to be less than the retention force of cap to the load mechanism. Different retention forces of cap16is accomplished in a number of ways, such as by a partial flexing of cap16relative to the socket or increasing the strength of snaps that hold cap16to the load mechanism.

Referring now toFIG. 2, a load mechanism24is depicted coupled to motherboard14proximate to socket12. Load mechanism24has a hinged load plate26that rotates from the depicted open position to a closed position that secures a processor in socket12. Load plate26has load mechanism attachment points28that are aligned with load mechanism attachment devices22when load plate26closes over a socket12having a cap16.FIG. 3depicts load plate26closing over socket12with a cap16coupled to socket12by interaction of socket attachment device18and socket attachment point20. As load plate26lowers over cap16, load mechanism attachment devices22contact load mechanism attachment points28. Leverage applied by the interaction of load mechanism attachment device22and load mechanism attachment points28passes to the opposing end of the arm at socket attachment device18, causing socket attachment device18to lift away from socket attachment points20.FIG. 4depicts a side view of the leverage applied through attachment device arm30so that coupling of load mechanism attachment device22to load mechanism attachment point28releases socket attachment device18from socket12. AlthoughFIGS. 3 and 4depict load mechanism24coupled to motherboard14in an open position followed by closing of load plate26over socket12, in alternative embodiments, load mechanism24may be attached to motherboard14with load plate26in a closed position.

Referring now toFIG. 5, a side perspective view depicts load plate26actuation from a closed position to an open position to lift cap16from socket12. Lifting cap16from socket12exposes pin field32, however, cap16is secured to load plate26to limit the risk of damage to pin field32. Load mechanism attachment devices22secure cap16by flexing against load mechanism attachment points28. Socket attachment devices18are released from socket12so that cap16lifts away from socket12with rotation of load plate26to an open position. As cap16lifts from socket12, the interaction of a socket guide34and cap guide36becomes apparent. During assembly of cap16to socket12, socket guide34interacts with cap guide36to aid in proper alignment of cap16over socket12.

Referring now toFIG. 6, a CPU38is depicted inserted into socket12while load plate26holds cap16away from socket12. Inserting CPU38into socket12covers the pin field to protect socket12from damage while cap16remains securely coupled to load plate26. Once CPU38is inserted into socket12, cap16is removed from load plate26as is depicted byFIG. 7. The presence of CPU38in socket12prevents damage from cap16inadvertently falling on socket12with an exposed pin field. Once cap16is removed from load plate26, load plate26is rotated to a closed position to secure CPU38in socket12. Load mechanism24may be any device that secures a processor into a socket, such as a land grid array (LGA) socket or other types of sockets that accept a processor.