GB189823300A - Improvements in and connected with Drilling Apparatus. - Google Patents

Abstract

23,300. Diehl, E. Nov. 5 Boring and drilling. -A templet is used in drilling or boring co-axial holes in machined work to avoid lining off, and consists of a plate B, Fig. 5, with guide-sockets L<1>, and having a hole D, Fig. 6, to fit over a spindle A. The spindle is clamped on the machined work M parallel with the drill, and may be merely a plain cylinder, or may have circular ends Z<1>, the intermediate portion being formed to fit the work. The other end of the plate B has a cross-bar F<1>, one end of which may be clamped on a machined surface, to exactly set the templet. To drill the co-axial holes L<2> at the other end, the templet is transferred to the other end of the spindle, which is shifted longitudinally if necessary, and the other end of the cross-bar clamped. When a boring-bar is used, two templets and spindles are used, the bar revolving in the corresponding sockets. To avoid using special templets for slightly different patterns, the plate B with the guide-sockets may be adjustably fixed on a bar T secured as before. The cross-bar F' may be replaced by other suitable known means for securing the free end of the templet.