Abstract: A slender tube (A) having an internal diameter of about 1 mm and a wall thickness of about 0.1 mm is used for the production of the tips of ball-point pens. After a cycle of combined linear and rotation-derived working steps, the tip has a front cross section (A') the internal diameter of which has been reduced to approximately the cross section of the ball (5); a central cross section (A'") the cross section of which corresponds to that of the original tube; and a rear cross section (A") with a cross section larger than the preceding cross section (A'"). The seat (S) against which the ball (5) is supported consists of conical recesses. The seat (S) is traversed by an opening into which penetrates the end (3') of a needle-like part (3), which part effects the ink transfer from a reservoir (2) to the ball.

Abstract: A ball point pen cartridge comprising an elongated tube having one end open, a socket mounted in the other, a ball rotatably mounted in the socket, a marking fluid within the tube in contact with the ball and means for hermetically sealing the other end of the tube with a hydraulic seal while exerting pressure on the fluid.