| 摘要 |
A bed alarm intended particularly for use with patients in hospitals and like establishments for indicating when a patient leaves his or her bed, said alarm being intended for connection to an alarm terminal point in respective bed places. The invention is characterized in that the alarm includes a pressure sensor (4) which functions to detect whether a patient is lying in bed or not and which is intended to be positioned in the bed and preferably between the bed-bottom and the mattress, and further includes an alarm activating circuit (5) incorporating an alarm inhibiting circuit (6), a delay circuit (7), an impulse unit (8) and an alarm output circuit (9). The alarm inhibiting circuit (6) functions to send a first signal to the impulse unit (8) only subsequent to the lapse of a predetermined starting period, and the delay circuit (7) functions to send a second signal to the impulse unit (8) when no load has been exerted on the pressure sensor (4) for a given predetermined time period. The impulse unit (8) functions to send an impulse to the alarm output circuit (9) when the impulse unit (8) receives both the first and the second signals; and in that the alarm output circuit therewith functions to produce an alarm signal through the alarm terminal (3). |
