Audible and/or visual alarm - is mounted on dentist's chair and actuable by patient to attract attention

摘要

An alarm enabling a dental patient to signal to the dentist comprises a hand control (1) having a tubular body (2) 12 cm long and 2-4 cm dia. with a push button (5) mounted at one end and electrically connected to a socket (4) at the opposite end. The control is linked through a detachable twin-core cable (7) to an alarm unit (8) containing a vibrator or oscillator and a loudspeaker (10). When the button is pressed by the patient a relay in the unit is energised to connect a battery power supply to the oscillator which thus drives the loudspeaker, as well as conveniently a flash light for dentists who are hard of hearing. The control (1) is conveniently plugged into one arm of the dentists chair with the unit mounted on the chair base. The control may be moulded as a grip for easier holding by the patient.