Retractable point protector for writing instruments
Abstract
Abstract 915,522. Writing instruments. JOHMANN, F. T. Dec. 22, 1959 [Jan. 21, 1959], No. 43544/59. Class 146 (3). A writing instrument having a resilientlymounted writing point, has a point protector movable in relation to the barrel between positions in which it respectively shields and exposes the point, the point protector being actuated by pressing its outer end, which is adjacent to the writing point, and the writing point against a rigid surface. A shown, the instrument comprises a two-part barrel 10, 11, whose parts are connected by a threaded, tubular plug 12. Slidably mounted in the open front end of the barrel part 11 is a sleeve 21 having series of ears 23 extending radially therefrom in the space between two tubular latch members 16, 17 which are frictionally secured in the barrel. The members 16, 17 are formed with opposed cam surfaces of the shapes shown in Fig. 6. The writing unit includes a reservoir 25, a feed tube 27 which is slidable in the plug 12 and the sleeve 21, and a ball-point 28. A spring 29 biases the writing unit forwards. The sleeve 21 is biased forwards by a spring 30 which is weaker than the spring 29 and tends to hold the ears 23 in contact with the latch member 16. In Fig. 1, the ears 23 are shown in the position 1 of Fig. 6, i.e. in the bottom of deep recesses 18 in the member 16, so that the sleeve 21 encloses the ball-point 28. To expose the ball-point the user presses the writing end of the pen against a rigid surface, thus forcing the sleeve 21 and the writing unit back into the barrel against the bias of their respective springs and bringing the ears 23 into contact with the member 17 (positions 2, 3, Fig. 6). When the pen is raised from the surface the sleeve and unit are carried forwards by their springs and the ears 23 pass through position 4 to position 5 so that the front end of the sleeve 21 is spaced to the rear of the ball-point 28. The point is concealed by a repetition of this procedure, the ears 23 passing through positions 6, 7, 8, 9 to 1<SP>1</SP>. In a modification, the ears 23 may be mounted, on the barrel and the members 16, 17 on the sleeve 21. Specification 792,185 is referred to.
Inventors
No inventors recorded.
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.