GB1004992A - Improvements in and relating to the nibs of ball point writing instruments andtheir manufacture - Google Patents

Abstract

1,004,992. Making ball point pens; end capping tubes; drawing. I.R.C. Ltd. May 16, 1963 [June 1, 1962; Jan. 2, 1963; April 30, 1963], Nos. 21137/62, 187/63 and 16857/63. Headings B3A, B3Q and B3V. [Also in Division B6] A method of making a writing extremity for a ball-point writing instrument having the socket offset comprises applying to a nib blank, after the socket and feed means up to and including the stage at which a complete writing extremity has been formed, an axial force which, or a component of which, permanently tilts the axis of the socket. A forged nib blank 10, Fig. 1, of, e.g. copper, having a tapered forward part 11 preferably at an inclined angle of 26 degrees, bores 13, 15, an axial feed duct 16 and with or without a ball 18 disposed in a socket 17 is initially drawn through a die 22 by relative movement of the die and a mandrel 25 which enters the bore 15 to effect a reduction in the internal and external diameters and the length thereof. The blank 10a is subsequently similarly drawn through a die 26, having an oval or elliptical bore slightly smaller than the diameter of the blank, with the aid of a mandrel 29 having an oblique end face 30, preferably equal to half the cone angle of the part 11, which abuts against the end face 20 of the bore 15a to tilt the feed duct and the ball socket so that one side of the conical extremity thereof is brought into alignment with the body of the blank. In a first modification the mandrel eccentrically engages the shoulder 14 of the bore 13 to tilt the blank extremity, Fig. 6 (not shown), in the region of the shoulder 14. In a second modification a parallel or stepped diameter reservoir tube, which may be supported by a sleeve 35, having an oblique end face is used in lieu of the mandrel and eccentrically engages the shoulder 14 to draw the blank thereabout, tilt the extremity thereof and attach the blank thereto to form a composite assembly. In a third embodiment a double bend, Figs. 12, 14 (not shown), is produced at the blank extremity by mandrels which engage the face 20, shoulder 14 during first and second drawing operations respectively. In a fourth modification the die 46 resembles a washer having a hole 47 of such a size that it makes contact with the blank rearwards of the ball socket. Preferably the hole is 0À010 inch smaller than the blank diameter and up to 0À005 inch smaller than the diameter of the member 33. The die 46, located by a flat, slot or tongue formed on the outer periphery thereof, is removably mounted in a holder 51, a member 33 having an oblique end face is mounted in a holder 53 with a blank thereon and the holders relatively moved together to draw the die over the blank to effect the reduction and tilting thereof about the member 33. The die washer is also pushed along the member 33 and left thereon to act as a location member for a plastic or metal capillary reservoir pushed thereon, Figs. 21, 22 (not shown). Alternatively a reduced end of a reservoir may be plugged in to an enlarged end of the member 33. In a fifth modification a blank having a bulbous shoulder 62 is partially drawn through a die 64 to draw the body portion in conjunction with a mandrel 29c so that the wall section thickness is reduced on one side thereof and the extremity is tilted. The end of the mandrel may be convex, rounded or partly cut-away and its region of engagement with the blank preferably one to three ball diameters rearwards of the centre of the ball and also rearwards of the region of engagement of the blank with the die. Specifications 564,172, 609,817, 973,563, 978,801 and 1,004,991 are referred to.