Methods and apparatus for sampling body fluid

A sampling device for sampling body fluid, comprising:

• a housing;
• a carrier mounted in the housing and carrying a hollow piercing element;
• a sample collection tube communicating with the piercing element;
• a driver mechanism mounted in the housing for driving the carrier forwardly to cut an incision in the skin and maintain an end of the piercing element in the incision;
• a stimulator mechanism on the housing for depressing a ring of body tissue in surrounding relationship to the incision to spread apart sides of the incision while urging body fluid toward the incision;
• a moving mechanism on the housing for moving the end of the piercing element relative to the incision to maintain the incision open while the stimulator mechanism urges body fluid thereinto;
• and
• a suction mechanism disposed on the housing for creating a suction in the tube for drawing-in body fluid through the piercing element and into the tube.

A device for obtaining a sample of body fluid through the skin comprising:

• a housing member containing a hollow piercing element for piercing the skin;
• a first spring member in the housing for urging the piercing element to protrude from a forward end of the housing sufficient to cut an incision through the skin;
• a stop member for defining a maximum penetration depth of the piercing element;
• a second spring in the housing for partially retracting the piercing element while maintaining a front end of the piercing element in the incision;
• a tube communicating with a rear end of the hollow piercing element;
• a moving mechanism for moving the piercing element relative to the incision to keep the incision open while body fluid is sampled therefrom, and
• a suction mechanism in the housing for creating a suction in the tube for drawing-in body fluid through the piercing element.