US Patent 7762106 Internally guided needle

For longitudinal shifting, a needle in accordance with the invention is provided with a longitudinal slit 14 that is disposed to accommodate a bearing element (19), for example, having the form of a strip (20). Whereas known needles are set in a guide channel and thus are held or guided between two guide flanks, the needle in accordance with the invention extends around a strip (20) and is guided on said strip. Thus, the needle is guided on two surfaces of the guide element (19) and the strip (20), respectively, said surfaces facing away from each other. The support section (4) and the bearing element (19) form a highly precise positioning or guide device.