Wheelchair cushion monitor and alarm apparatus

摘要

Apparatus for reminding patients with limited movement to perform movements at regular intervals to reduce the risk of pressure sores is described. A load sensor (11) positioned beneath the patient senses the pressure exerted by the weight of the patient. A movement interval timer (MIT) (14) monitors the output of the sensor (11) during a predetermined period. If the pressure is not relieved during this period a signal is fed to the input (13a) of an alarm (13) and to a push-up error counter (PEC) (15), incrementing the counter by one. If the pressure on the sensor (11) is relieved, the MIT (14) is reset. Successive signals resulting from timed periods without movement are fed to the alarm (13) and the PEC (15) and if the accumulated number of signals exceeds a predetermined number a flip-flop (16) is enabled actuating the alarm (13). The alarm signal continues until the patient moves to relieve the load on the sensor, resetting the MIT (14) and PEC (15).