GB626744A - Case or housing incorporating a device for pointing pencil leads - Google Patents

Abstract

626,744. Pencil sharpeners. STEINER, P., and THURNHEER, J. Feb. 19, 1947, Nos. 4867 and 4868. Convention dates, Feb. 20, 1946 and June 21, 1946. [Class 146 (iii)] A pencil-sharpening device incorporated in a housing comprises at least one rotatable funnel-type sleeve for a lead holder or propelling pencil, a mechanism for simultaneous rotation of the sleeve and of a grinding member, means for pressing the leads elastically against the grinding member and means for limiting the extent to which the lead is pressed so that the process of grinding may be automatically interrupted as soon as the lead is pointed. The funnel-type sleeve 57 is accommodated in a bush 64 which is mounted by means of a spherical boss 65 in a bore in the housing 41 and can be pivoted on bolts 66. A spring 67 presses the bush 64 so that the lead 69 is pressed against the grinding wheel 61 and a screw 68 acts as a stop to limit the pivotal movement of the bush. A plate 44 separates the wheel 61 from the operating mechanism and the dust collects in the removable bottom 42 of the housing. A stop 70 is provided for adjusting the length of the lead so that it bears against the wheel 61. The sleeve 57 and wheel 61 are rotated simultaneously by means of a gear wheel 48 which engages a toothed rim on the sleeve 57 and a gear wheel 47 on the axle 46 of a fly wheel 59 to which the grinding wheel is secured. The wheel 48 is rotated in one direction only by a pawl 56 thereon engaging a ratchet 55 on a sleeve 50 freely rotatable on the axle 49. The sleeve 50 has a gear wheel 51 actuated by a hollow-toothed rack 52 which is forced out of the housing 41 by a compression spring 53 in its hollow bore and is pressed back into the housing by a stud 54, by hand. For sharpening compass leads on one side only, the funnel-type sleeve 75 which is designed to accommodate part of the compass leg, is rotated through a maximum of 120 degrees by means of a catch 76 which is limited by stops 77, 78 fastened to the toothed rack 52, the grinding wheel being internally tapered as shown. In a modification in which compass leads are sharpened on the outside of a solid grinding wheel, the screw stop is on the outside of the housing and the spring is situated below the pivot point of the bush 64a. In a modification showing only one propelling pencil to be sharpened on a solid grinding wheel, the driving mechanism comprises a winding drum with a pulling cord to tension a spiral spring in the drum, or a pulling cord may be so connected to the drum that alternate pulls on the two ends of the cord rotates the drum, or an electric motor may be used. The Specification as open to inspection under Sect. 91 comprises also a modification in which the pencil is inserted into a non-inclinable sleeve and is pressed against the grinding wheel by its own weight. This subject-matter does not appear in the Specification as accepted.