Abstract: A biopsy device includes a first cannula and a second cannula disposed co-axially with the first cannula. A first gear is fixedly attached to the first cannula. A second gear is fixedly attached to the second cannula. A torsion spring is interposed between the first gear and the second gear. The torsion spring is connected to each of the first gear and the second gear. A ratchet drive mechanism is configured to wind the torsion spring to store energy during a cocking operation, and is configured to release the energy stored by the torsion spring during a firing operation to drivably rotate the first gear to rotate the first cannula relative to the second cannula.

Abstract: A biopsy device includes a first cannula having a first aperture, a second cannula having a second aperture, and a driver unit. The second cannula is disposed co-axially with the first cannula. At least one of the first aperture and the second aperture has a cutting edge. The driver unit has a ratchet drive mechanism operatively coupled to the first cannula and the second cannula. The ratchet drive mechanism includes a first gear fixedly attached to the first cannula. A second gear is fixedly attached to the second cannula. A torsion spring has a first end portion connected to the first gear and a second end portion connected to the second gear. The torsion spring stores energy which when released drivably rotates one of the first gear and the second gear relative to the other of the first gear and the second gear.

Abstract: A biopsy device includes a first cannula disposed co-axially with a second cannula. A ratchet drive mechanism is operatively coupled to the first cannula and the second cannula. The ratchet drive mechanism includes a first gear, a second gear and a torsion spring. The first gear is fixedly attached to the first cannula. The second gear is fixedly attached to the second cannula. A second side surface of the second gear is oriented to face a first side surface of the first gear. The torsion spring is interposed between the first gear and the second gear. The torsion spring has a first end portion inserted into a hole of the first gear and has a second end portion inserted into a hole of the second gear. The torsion spring stores energy which when released drivably rotates one of the first gear and the second gear relative to the other.

Abstract: A biopsy device includes a first cannula disposed co-axially with a second cannula. A ratchet drive mechanism is operatively coupled to the first cannula and the second cannula. The ratchet drive mechanism includes a first gear, a second gear and a torsion spring. The first gear is fixedly attached to the first cannula. The second gear is fixedly attached to the second cannula. A second side surface of the second gear is oriented to face a first side surface of the first gear. The torsion spring is interposed between the first gear and the second gear. The torsion spring has a first end portion inserted into a hole of the first gear and has a second end portion inserted into a hole of the second gear. The torsion spring stores energy which when released drivably rotates one of the first gear and the second gear relative to the other.

Abstract: A biopsy device includes a first cannula having a first aperture, a second cannula having a second aperture, and a driver unit. The second cannula is disposed co-axially with the first cannula. At least one of the first aperture and the second aperture has a cutting edge. The driver unit has a ratchet drive mechanism operatively coupled to the first cannula and the second cannula. The ratchet drive mechanism includes a first gear fixedly attached to the first cannula. A second gear is fixedly attached to the second cannula. A torsion spring has a first end portion connected to the first gear and a second end portion connected to the second gear. The torsion spring stores energy which when released drivably rotates one of the first gear and the second gear relative to the other of the first gear and the second gear.

Abstract: A biopsy device includes a first cannula having a first aperture, a second cannula having a second aperture, and a driver unit. The second cannula is disposed co-axially with the first cannula. At least one of the first aperture and the second aperture has a cutting edge. The driver unit has a ratchet drive mechanism operatively coupled to the first cannula and the second cannula. The ratchet drive mechanism includes a first gear fixedly attached to the first cannula. A second gear is fixedly attached to the second cannula. A torsion spring has a first end portion connected to the first gear and a second end portion connected to the second gear. The torsion spring stores energy which when released drivably rotates one of the first gear and the second gear relative to the other of the first gear and the second gear.