Issue 22

D. Gentile et alii, Frattura ed Integrità Strutturale, 22 (2012) 85-92; DOI: 10.3221/IGF-ESIS.22.09 90 Gas spring has been selected from commercials catalogue by ACE: maximum extension range 100 mm, maximum load 1440 N, Fig. 6. Power transmission has been realized by a system of toothed belts and pulleys, Fig. 7. Belts are made in “polychloroprene” with steel core. Pulleys has type HDT (European standards) with 5 mm pitch for belts 15 mm width. ( a) (b) Figure 5 : Spindles group: a) total view; b) load system details. Figure 6 : Gas spring. (ACE commercial catalog). Figure 7 : Belts and Pulleys. Most of the commercial components, like load cells or springs has been assembled in order to allow their substitution for eventual upgrades. Spindles are mounted on rails to allow different sample’s length. Also the control system has been designed in order to allow easy upgrade: for each sample there is a cycles counter and an encoder connected with a computer that allows to control separately each related load cell by a dedicated software. Control system provides the possibility to send external trigger at defined numbers of cycles in order to allow measure by video camera or other kind of instruments.