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TrackPoint design with improved comfort and traction

IP.com Disclosure Number: IPCOM000014203D
Original Publication Date: 2000-Aug-01
Included in the Prior Art Database: 2003-Jun-19
Document File: 2 page(s) / 58K

Publishing Venue

IBM

Abstract

A concave shape for the TrackPoint input device results in more effective operation and increased long-term comfort.

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TrackPoint design with improved comfort and traction

A concave shape for the TrackPoint input device results in more effective operation and increased long-term comfort.

Long term usage of the convex type of trackpoint results in a sore finger. This is because of the way the TrackPoint device is shaped. Figs. 1 and 2 illustrate the side profiles of both types of trackpoint. Fig. 1 shows the smooth type, while Fig. 2 shows the rough type.

1 2 3 4

After continuous usage, by body oils and sweat causes the surface of the smooth type (Fig. 3) to become slippery. This requires additional downward pressure to operate. Eventually a bothersome "trackpoint-sized" depression appears on the operating finger. The rough type (Fig. 4) irritates the finger surface and renders it extra sensitive - an unpleasant sensation. As with the smooth type, after continuous use, a trackpoint-sided indentation appears on the operating finger.

Fig. 5 shows that the curvature of the finger matches the curvature of the TrackPoint device. The sequence in Figures 6-8 shows that as the two convex surfaces come together (Fig. 6) the contact patch (Fig. 7) is small, which causes slippage (Fig. 8). The flesh in the finger must become concave to adopt the shape of the TrackPoint, to increase the size of the contact patch.

5 6 7 8 9

The solution is to change the shape of the TrackPoint so that the finger mates comfortably with it, as shown in Figs.10 and 11. With this new shape, the contact patch is mu...