Pressure reduction mechanism, puncture device, blood analysis device, and sensor mounting mechanism

Abstract

Provided are a decompression mechanism capable of performing a desired pressure reduction by simple operation and having improved operability, a puncture device, a blood analysis device, and a sensor mounting mechanism. A needle puncturing device () is provided with: a piston () having at one end thereof an end part () for forming a part of a sensor mounting mechanism () and at the other end an end part () for slidably supporting a rod () of a lancet section (); a cylinder () for slidably containing therein the end section () of the piston (); and packing () mounted to the inner periphery of the end part () of the piston () and maintaining the air-tightness of the outer periphery of the rod (). When the piston () is moved in the direction toward the cylinder () with a skin contact part () in contact with the skin, the volumes of an internal space () and a pressure reduction chamber () which are sealed by packing () are increased to produce a reduced pressure.