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Gauge to measure hole distance from structural features Disclosure Number: IPCOM000249621D
Publication Date: 2017-Mar-08
Document File: 3 page(s) / 389K

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The Prior Art Database

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Gauge to measure hole distance from structural features

This disclosure concerns the measurement of hole positions to steps, pockets or other features in difficult to access areas like the rib feet on aircraft wings.   Measurement of holes positions is often required to determine the accuracy/capability of hole positions and to determine whether fasteners and nut caps are likely to come into contact or clash with adjacent features. 

Fig 1 examples of fastener positions which are difficult to measure


Traditional measuring equipment such as Vernier/digital callipers is very versatile but the length of the instrument prevents measurement in confined areas (see Figure 1).  If measurements can be made at all, their accuracy is diminished as it may be difficult to align the calliper and direct measurement from the hole centre cannot be made.  Sophisticated devices such as laser scanners and probes (faro arm) are effective but are expensive and require time and expertise to make and interrogate measurements.

The gauge provides a quick and simple way of measuring the distance of a hole to a step or adjacent feature on part of a wing or other structure where access with conventional callipers is restricted.

The gauge consists of:

·         A cylindrical plug that fits into the hole

·         A body with the outer form shaped like an Archimedes spiral with makings/graduations indicating the distance from either the hole centre or from the fastener diameter used in that particular hole.