Adjustable keyboard tray for a desk

What is this patent about?

’229 is related to the field of ergonomic office furniture, specifically focusing on adjustable support mechanisms for computer peripherals. Traditional keyboard trays often require users to manipulate multiple independent knobs or levers to set both the elevation and the tilt of the tray, leading to a cumbersome and non-intuitive adjustment process. The background context involves the need for a simplified mechanical interface that allows a user to reposition a workspace component in multiple dimensions simultaneously through a single point of control.

The underlying idea behind ’229 is the use of a friction-based compression stack that binds multiple moving parts together using a single cam-actuated clamping force. Instead of having separate locking mechanisms for the main support arm and the tray pivot, the invention routes the movement of these components through a shared interface. By applying lateral pressure across a series of overlapping plates and links, the system can transition from a completely fluid state to a rigid, locked state with one motion, effectively freezing the entire geometry of the assembly at once.

The claims of ’229 focus on a mechanical linkage system comprising a sliding base, a connecting arm, and a limit link that works in tandem with an eccentric cam locking device. The independent claims describe how the connecting arm is pivotally attached to both the base and the keyboard support, while the limit link—a multi-layered strip—is pinned to the base and extends toward the support. The core of the claim is the drive assembly, which uses the rotation of the eccentric cam to either squeeze or release this limit link against the connecting arm, thereby controlling the mobility of the entire structure.

In practice, the invention operates by utilizing the eccentric cam as a high-leverage toggle. When the user rotates the lever, the cam’s profile shifts from its short axis to its long axis, driving an outer sleeve to compress a stack of resilient washers and the limit link. This compression creates enough friction to prevent the inner shaft from sliding within the elongated hole of the limit link and prevents the connecting arm from pivoting. Because the locking force is applied at the junction where the arm meets the tray, it simultaneously arrests the height-adjusting pivot at the base and the tilt-adjusting pivot at the tray.

This approach differs from prior solutions by eliminating the need for secondary adjustment points. While conventional trays use separate pins and curved slots that must be tightened individually, this design employs a shared clamping axis that acts as both a pivot point for the tray and a brake for the height-adjustment link. By integrating a restitution spring to counter the weight of the keyboard, the inventor has created a system where the user can unlock a single lever, float the tray to the perfect ergonomic position, and lock it instantly without losing the desired angle or height during the process.