Southwest Research Institute

Colin Electronics Co., Ltd.

Nippon Colin Co., Ltd.

Donald J Shirley

Merle E Converse

Thomas E Owen

H Herbert Peel

William H McGinnis

John P Prudhomme

A cardiovascular monitor having improved safety features and data transmission ability. Sensing devices placed on a patient's body, such as electrocardiogram electrodes and phonocardiogram microphones, are electrically isolated from the data recorder and AC powerline, thereby protecting the patient from dangerously high voltages existing in the recorder and the external power source. Isolation amplifiers are employed in the signal conditioning circuitry at the front end of the recorder. Special isolation transformers are also used to prevent ground loop currents between the signal conditioner and the recorder thus minimizing noise due to powerline leakage. Similarly, isolation amplifiers are used during the playback mode between the recorder and a data processor to avoid ground loop currents between the recorder and the processor.

Cardiovascular monitor

An interference resistant biomedical transducer for monitoring the acoustic output of a patient's cardiac or respiratory system which provides a high degree of rejection of acoustic noise and spurious electromagnetic signals. The transducer comprises a piezoelectric diaphragm assembly having electrodes which produce a differential output signal. The transducer housing includes a massive metal disc and a compliant handle which provide a mechanical filter to remove undesired signals such as those related to motion of the patient and ambient acoustic noise.

Interference resistant biomedical transducer

An acoustic transducer with high sensitivity and low resonance frequency is constructed of a cylinder having inner and outer layers rigidly bonded together. At least one layer is a thickness poled piezoelectric material. The cylinderical can be closed by end caps to shift nodal locations.

Cylindrical bender-type vibration transducer

Growing community of inventors

Boerne, TX, United States of America

Donald J Shirley