Shear muscle force crops copper

Innovative fluidic muscles from Festo have been deployed in a high force application to assist with the manufacture of electrical starter motors for buses and trucks

. The application calls for simultaneous cropping of copper conductors totalling 1.25 sq. in. in cross section. Festo's distributor Blackson & Kenridge is behind the application which delivers forces of more than 30,000 lbf/ to crop copper conductors in a production machine designed and built by Hamlyn Engineering of Middlesex. Rather than use six 125mm diameter cylinders of 50mm travel arranged in a vertical stack and driven in unison to operate the rotary guillotine mechanism, Blackson & Kenridge recommended using eight Festo fluidic muscles, each one only 40mm in diameter. Rather than using air to drive a piston, the muscle deploys a mesh of interwoven fibres surrounding a hollow flexible core. Introducing air to the core deforms the structure, generating movement and an axial force. The muscle offers performance advantage in terms of immense power along with smooth operation and very light weight. A muscle weighs just one tenth that of a metal cylinder of equal inner diameter, yet generates forces typically ten times as great. During the customer's motor production process, 27 strips need to be cut to length in situ. The design team needed to develop a solution capable of applying the force and control, as cutting copper requires between 22,000 and 30,000 lbf/in2 force. Hamlyn, along with sister company Camberley Automech, designed a bar cropper machine – a rotary guillotine mechanism comprising two circular die with 27 wire eroded holes to take the copper strips. DP Pointers: * The data logger has a logging module no larger than a watch face. * It uses inductive technology rather than communication ports and solves any data corruption problems when downloading information * The devices are being used in food applications, packaging traceability and long-term submersion applications.