US Patent 8448496 Piezoelectric coagulation sensors

This invention provides methods and devices to measure physical characteristics of sample fluids. Samples are introduced into a sample chamber in contact with a mechanically oscillating working member. The vibrations are received by a piezoelectric sensor transducer and correlated to a sample characteristic, such as viscosity or density. The devices include a sample chamber in contact with one or more working members actuated by a piezoelectric actuator and/or monitored by a piezoelectric sensor.