ANALYSIS AND DESIGN ROTARY-TYPE SETBACK LEAF S+A MECHANISMS
Abstract
A procedure is described for designing S + A setback mechanisms of the rotary-leaf and spring type to obtain optimum safety and reliability. The design procedure, developed from a mathematical analysis, is described in detail. This procedure is formulated so that little mathematical background is required to use it. An analytical study is made of the effect of varying the mass of the leaves upon the accidental drop safety of the mechanism. The drop safety is defined as the absolute minimum velocity change that can possible arm the device. This figure of merit is derived and evaluated for each set of leaves. This study was made for both fast and slow-rising acceleration curves, and for restraining springs with both fat and steep spring rates. The results of the analysis in each case indicate that leaves of equal weight are about as safe and reliable as combinations of leaves of varying weights. Also the mechanism performed much as though a constant acceleration was applied to it. The main assumption of the analysis was that friction has an average effective value.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 11, 1964
- Accession Number
- AD0439337
Entities
People
- William E. Ryan
Organizations
- Harry Diamond Laboratories