US-20260128541-A1 - BOARD-TO-BOARD MECHANICAL CONNECTION CONFIGURATION

US20260128541A1US 20260128541 A1US20260128541 A1US 20260128541A1US-20260128541-A1

Abstract

A retention mechanism for installing an expansion card in a computer system comprises at least one ratchet rack mounted in a fixed location in the chassis and a corresponding sliding retainer adapted to slide along the ratchet rack in a vertical direction. The ratchet rack can include a plurality of rack gear teeth and the sliding retainer can include a pawl that is biased into engagement with the rack gear teeth. When the expansion card is inserted into an edge connector socket, the sliding retainer slidingly engages the ratchet rack to linearly move in the vertical direction to contact the expansion card and the pawl is urged into engagement with the rack gear teeth.

Inventors

Tsung Ho CHEN

Assignees

Aivres Systems Inc.

Dates

Publication Date: 20260507
Application Date: 20251230

Claims (20)

1 . A retention mechanism for installing an expansion card into an edge connector socket in a computer system comprising: a ratchet rack adapted to be mounted to a fixed location in a chassis of the computer system, the ratchet rack comprising a plurality of rack gear teeth linearly aligned in a vertical direction associated with the chassis; and a sliding retainer slidably along the ratchet rack in the vertical direction and adapted to contact the expansion card, the sliding retainer comprising a lever arm with a pawl urged into engagement with the plurality of rack gear teeth to selectively lock the sliding retainer along the vertical direction.
2 . The retention mechanism of claim 1 , wherein the sliding retainer comprises a card channel for receiving a rear card edge of expansion card.
3 . The retention mechanism of claim 2 , wherein the card channel protrudes in a longitudinal direction perpendicular to the vertical direction.
4 . The retention mechanism of claim 1 , wherein the sliding retainer comprises a retainer foot adapted to abut the expansion card in the vertical direction.
5 . The retention mechanism of claim 1 , wherein the ratchet rack and the sliding retainer are coupled by a linear bearing.
6 . The retention mechanism of claim 5 , wherein the ratchet rack is located on a ratchet panel having a planar shape.
7 . The retention mechanism of claim 6 , wherein the linear bearing comprises a rail structure and the sliding retainer comprises a saddle block that slidingly couples to the rail structure.
8 . The retention mechanism of claim 7 , wherein the rail structure comprises a flange offset from a forward surface of the ratchet panel and the saddle block comprises a saddle catch configured to be received between the flange and the forward surface of the ratchet block.
9 . The retention mechanism of claim 7 , wherein the lever arm is pivotally connected to the saddle block by a living hinge.
10 . The retention mechanism of claim 9 , wherein the lever arm comprises a finger pull latch adapted to rotate the lever arm with respect to the living hinge to release the pawl from the plurality of ratchet gear teeth.
11 . The retention mechanism of claim 6 , wherein the lever arm is pivotally connected to the saddle block at a pivot axis perpendicular to the vertical axis.
12 . The retention mechanism of claim 7 , wherein the ratchet panel comprises a plurality of ratchet racks and the sliding retainer comprises a saddle block adapted to slidingly couple to the plurality of ratchet racks.
13 . The retention mechanism of claim 6 , wherein the ratchet panel comprises an upper stop and a lower stop constraining vertical travel of the sliding retainer.
14 . The retention mechanism of claim 13 , wherein the upper stop comprises a cantilevered arm depressible with respect to a forward surface of the ratchet panel.
15 . A method of installing an expansion card into an edge connector socket in a computer system comprising: fixedly securing a ratchet rack internally in a chassis of the computer system, the ratchet rack comprising a plurality of ratchet gear aligned in a vertical direction associated with the chassis; inserting a lower card edge of the expansion card in the vertical direction into the edge connector socket; slidingly engaging a sliding retainer to the ratchet rack and sliding the sliding retainer in the vertical direction to contact the expansion card; and urging a pawl on the sliding retainer into engagement with the plurality of rack gear teeth on the ratchet rack to lock the sliding retainer in the vertical direction.
16 . The method of claim 15 , wherein the pawl is urged into engagement by a living hinge on the sliding retainer.
17 . The method of claim 15 , further comprising uninstalling the expansion card by pivoting the living hinge to release the pawl from the plurality of rack gear teeth.
18 . A retention mechanism for retaining a plurality of expansion cards to a corresponding plurality of edge connector socket in a computer system, the retention mechanism comprising: a ratchet panel comprising a plurality of ratchet racks, of the plurality of ratchet rack each comprising a plurality of rack gear teeth aligned linearly in a vertical direction associated with a chassis of the computer system, the plurality of ratchet racks spaced apart in a lateral direction perpendicular to the vertical direction; and one or more sliding retainers, each sliding retainer adapted to slide in the vertical direction along a pair of ratchet racks adjacent to each other, each sliding retainer comprising a pawl urged to engage with the rack gear teeth on the pair of ratchet racks to lock the sliding retainer in the vertical direction.
19 . The retention mechanism of claim 18 , wherein each sliding retainer comprising a pair of card channels, each card channel adapted to receive a rear card edge of a corresponding expansion card.
20 . The retention mechanism of claim 18 , wherein each sliding retainer comprises a retainer foot adapted to abut the expansion card in the vertical direction.

Description

TECHNICAL FIELD This patent application relates to components for computing systems and, in particular, to a retention mechanism for mechanically connecting and securing an expansion card within a computer system. BACKGROUND Computer systems are assembled from various electronic components and devices that are communicatively interconnected and physically arranged and accommodated in a common chassis or enclosure. The computer systems are often modularly designed for flexibility and scalability to improve or change functionality and the capabilities of the computer system. A common design for modular computer systems is to include one or more expansion sockets located on a printed circuit board such as the motherboard or a dedicated expansion board accommodated internally inside the computer enclosure or chassis. To modify or improve the computer system, additional circuit boards with the appropriate electronic components mounted thereon can be inserted and electrically connected to the connector sockets to communicate and interact with the computer components previously included with the computer system. The new combination expands the functionality of the computer system. The added circuit boards are typically configured as planar printed circuit cards referred to as expansion cards, daughter boards, or riser cards, and the expansion sockets are configured as elongated edge connectors including a slot to receive an edge of the expansion card. The expansion cards, for example, may be oriented vertically so the cards can be placed into the edge connector sockets in an upright configuration, perpendicular to a horizontally positioned expansion board or motherboard. The orthogonal arrangement of the expansion card and motherboard is referred to as an orthogonal board-to-board connection and advantageously allows for a plurality of expansion cards arranged parallel with one another to be connected to a corresponding plurality of edge connector sockets mounted in parallel on the motherboard. The right-angled connection between the expansion card and the motherboard may benefit from an arrangement or mechanism to assist in retaining the components together. For example, specific components such as integrated circuits may be mounted to one or more rigid printed boards (PCBs) configured for the routing of electronic data signals and electrical power that may be accommodated within the enclosure. The printed circuit board may include a rigid planar substrate made of an insulative material such as phenolic resin having electrically conductive traces disposed on the planar surfaces or embedded in the laminated structure of the board. Electronic devices mounted to the planar surface of the printed circuit board are communicatively connected by the conductive traces. The arrangement and cooperative operation of the electronic components are responsible for the computational and processing functionality of the computer system. Typically, multiple printed circuit boards having different electronic components arranged for different purposes may be installed in the same chassis and must communicate electronically with one another. Although communication can be established by wires and cables, sometimes it is desirable to physically connect two printed circuit boards directly together, eliminating wires and improving electronic communication. Direct physical connection between printed circuit boards communicatively links the local communication busses thereon improving the transfer of data signals and electrical power. Various orientations and arrangements are available for directly connecting two or more printed circuit boards together. For example, two printed circuit boards can be oriented orthogonally at right angles and thus perpendicularly intersect each other. Right angled connectors or edge connectors can be used to communicatively interface the orthogonal boards. In another example, two printed circuit boards can be placed in a parallel, spaced apart orientation. Such a board-to-board arrangement may be referred to a parallel stacked or mezzanine arrangement SUMMARY OF THE DISCLOSURE To install and retain one or more expansion cards internally in a computer system, the disclosure describes a retention mechanism assembled from a plurality of interacting components configured for generating and applying retaining forces upon the expansion cards. The retention mechanism includes a ratchet rack that is adapted to be mounted to a fixed location in a chassis of the computer system. The ratchet rack includes a plurality of rack gear teeth linearly aligned in a vertical direction of the chassis. The retention mechanism also includes a sliding retainer that can slide along the ratchet rack in the vertical direction and that is adapted to contact the expansion card. The sliding retainer includes a lever arm with a pawl urged into engagement with the plurality of rack gear teeth to selectively lock the sliding retainer along