Automatic Feeding of Temporary Fasteners in Confined Spaces

Single Sided Slave Fasteners (SSSF) or Single Sided Temporary Fasteners (SSTF) are increasingly replacing more cumbersome and manual tools for temporary doweling and clamping of aerospace components during assembly. Their ability to clamp provide doweling and clamping reduce the amount of tooling required. Due to their low profile and blind (one-sided) capability, the key benefit of this new technology is the ability to install these fasteners with automated machines. Electroimpact has developed machines to feed primarily SSTF bolts made application-specific by Centrix LLC [ 1 ]. The application discussed in this paper presented problems of confined spaces where a variety of fasteners were required to be fed automatically. To address this, Electroimpact developed new Bolt Injector and Bolt Inserter technology to feed multiple diameters of SSTF bolts in a very small package. Application-specific SSTF were designed such that multiple diameters could be fed through one feed tube. Additionally, the new technology produced diameter and length checking ability. Previously, ancillary systems were often needed to provide this functionality or the functionality was not offered at all. The tools developed for this application provide automatic feeding of a variety of fasteners through one tube into a confined space. Length checking, diameter checking and absence of tool change are further benefits of this system. The resulting tools provide increased functionality in an increasingly smaller package.