Patent ID: 7561042
Filing Date: 2009-07-14
Classification: G01H

Abstract:
1. An alarm for the opening of a moveable portal barrier, the alarm comprising: (a) a first assembly adapted for attachment to the moveable portal barrier; (b) a second assembly adapted for attachment spaced apart from but proximate to the moveable portal barrier; (c) a vibration inducing ridge and a vibratable prong, the vibratable prong having a vibratable free end, one of the vibration inducing ridge and the vibratable prong being attached to the first assembly and the other of the vibration inducing ridge and the vibratable prong being attached to the second assembly such that the movement of the first assembly with respect to the second assembly causes the vibratable prong to contact and move relative to the vibration inducing ridge so that the ridge mechanically causes the vibratable prong to vibrate; and (d) a sensor for sending vibration of the prong; wherein the first assembly is alternatively moveable between (i) a closed position wherein the first assembly and the second assembly are proximate to one another and cooperate together to enclose the vibratable end of the vibratable prong and the vibration inducing ridge so that the alarm is largely tamper-proof and (ii) an open position wherein the first assembly is spaced further apart from the second assembly.