Safety switch with dual anti-tamper
AssigneeIdem Safety Switches Limited
InventorsMedi Mohtasham, Hamed Faridfar, Vincent Crolla, Timothy Jennings
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Abstract
A safety interlock switch with coded interlocking to provide tamper resistance, the coded interlocking having two differently coded technologies 8,10; 16,18. In a preferred embodiment one technology is mechanical in the form of a coded-cam system operated by a coded-tongue 8, the other is electronic comprising a non-contact coded RFID sensor 16,18, and wherein the switch is only enabled when the two different codes have been correctly applied.
Claims13
A safety interlock switch which has coded interlocking to provide tamper resistance, characterised in that the coded interlocking includes two differently coded technologies, wherein one of the coded technologies is mechanical, using a coded cam system operated by a coded tongue, and the other of the coded technologies is electronic, including a non-contact coded RFID sensor, and wherein the switch comprises safety means which checks that the two different codes have been correctly applied before enabling a safety output of the switch which provides machine control.
A method of operating a safety interlock switch which includes a coded rotary cam system operated by a coded tongue, the switch being of the positively operated type in which the switch must be positively operated by the cam system in order to switch off the power to attendant machinery, characterised in that the switch further comprising a second interlock in the form of a non-contact RFID sensor, the method comprising the steps of firstly inserting the coded tongue to rotate the cam, secondly checking the code of RFID sensor when the tongue is part inserted to ensure that the code is correct and enabling power only when both interlocks are correctly coded.
Dependencies are inferred from the claim text.