This invention relates to a work station keyboard support elevation apparatus which permits a person using a keyboard, or a mouse, to adjust the keyboard to heights satisfactory for persons working in seated or standing positions. Workers are often required to perform tasks in a sitting position at a work station, which reduces blood flow through the legs and induces worker fatigue. The herein disclosed keyboard support is readily adjustable by the worker to an elevated position allowing the worker to work in a standing position. It is also easily adjusted back to a suitable worker sitting position. Monitor supports have previously been provided by which the monitor height can be adjusted and some monitor supports permit the monitor to be tilted about a horizontal axis parallel to the face of the monitor. These adjustments facilitate use of the monitor while the worker is standing but do not elevate a counter supported keyboard to a convenient height for the standing worker.
The herein disclosed vertically adjustable keyboard support includes a horizontal base plate adapted to rest flat on a desk top or work station counter and an upper horizontal keyboard support plate. The adjustable keyboard support is a stand alone portable item. It need not be attached to adjacent structure. The upper keyboard support plate is interconnected to the horizontal base plate by a scissor linkage leg structure permitting keyboard height adjustment for various height persons when either in a sitting position or a standing position. The scissors linkage support structure includes a pair of U-shaped components, each having a pair of legs with proximal ends extending from, and rigidly secured to, a horizontal tie bar. Corresponding legs of the two U-shaped components are interconnected intermediate their ends on a common horizontal axis to form a pair of scissors support linkages. The tie bar of one of the U-shaped components is pivotally connected on a horizontal axis to the underside of the keyboard support plate near one of its fore and aft edges. Parallel ridges on the underside of the keyboard support plate provide a plurality of horizontally spaced notches which are releasably and individually engageable by the tie bar of the other U-shaped component to provide a wide range of height adjustment for the keyboard support plate.
The invention is illustrated in the accompanying drawings, in which:
Referring particularly to
The scissors linkage support includes a pair of U-shaped leg structures 21, 22 interposed between the upper and lower plates 12, 16. The leg structure 21 includes a pair of parallel legs 26, 27 rigidly interconnected by a horizontal connector 28 which is pivotally connected to the underside of the upper support plate 12 on a horizontal axis 40. The leg structure 22 includes a pair of parallel legs 31, 32 and a horizontal connector 33 between and rigidly connected to the upper ends of the legs 31, 32. A pivot pin 46 pivotally connects legs 21 and 31 on a horizontal axis 47 and a pivot pin 48 pivotally interconnects legs 27, 32 on the axis 47. The horizontal connector 33 is adapted for insertion into downwardly open equally spaced parallel notches 34 formed by parallel ridges 36 of a releasable retention structure or mat 37 rigidly secured to the underside of the upper plate 12. The axes 40, 47 are parallel to the notches 34. Cups 49 made of elastic anti skid material are mounted on the lower ends of the legs 26, 27, 31, 32.
The U-shaped leg structures 21, 22 are hollow, have substantially equal length legs and are preferably formed from aluminum tubing or the like. The horizontal connector 28 of the U-shaped structure 21 is pivotally connected to the rear underside of the upper plate 12 on a horizontal axis 40 by a pair of pivot blocks 41, 42. The lower ends of the legs 31, 32 are pivotally connected by pivot pins 51, 52 to upturned vertical tabs 38, 39 of the lower plate 16 on a horizontal axis 30. The long grooves 34 of the releasable connector formed by the mat 37 provide a stable connection with the cylindrical connector 33.
In the illustrated embodiments of the invention the upper and lower plates 12, 16 remain parallel in all positions of height adjustment. The low collapsed height shown in