GB503867A - Drilling device with automatic advance of the tool - Google Patents

Abstract

503,867. Drilling-machines. STABEG APPARATEBAUGES., and SALANSKY, F. Oct. 15, 1937, No. 28168. [Class 83 (iii)] A portable drilling-machine, particularly for operating on railway rails in situ, has a frame 3 for clamping to a rail foot &c. and carrying a sleeve 10 which encloses a frictionally-driven spring-feed for the drill 16. The frame 3 consists of two spaced side members joined at the ends by bars 4, 5 whereof the former carries a claw 7 for engaging the rail foot 2 and the latter receives a screw 9 engaging a slide 6 which also carries a claw 8. A pillar 11, preferably cylindrical, is vertically and rotatably adjustable in the slide and is clamped by a screw 12, a scale 13 facilitating the vertical adjustment. The sleeve. 10 is secured to the pillar 11 and has a bearing 19 for an enlargement 15 on the drill spindle 14. A feed sleeve 21 is screwed at 20 in the sleeve 10 and engages through a thrust bearing 29 with a spring 28 abutting on the enlargement 15. Compression is applied to the spring by a thumb nut 27 screwing on the end of the spindle and pressing a driving handle 26 and a square socket 25 against a steel wear plate 22 on the sleeve 21. In operation, rotation of the handle 26 rotates the sleeve 21 through friction at 22 until the drill engages the work, whereupon the spring 28 becomes further compressed and the friction at 22 is relieved to allow the sleeve 21 to remain stationary. As the drill is fed into the work by the spring 28, the friction at 22 increases until it is sufficient to rotate the sleeve 21 again and thus increase the feed. In a modification the sleeve 21 screws on the outside of the sleeve 10 and is rotated by one or more axially arranged screws on the handle-boss engaging the friction plate 22, the screws being axially adjustable to vary the feed in the same manner as is possible by adjustment of the nut 27 and in another modification the driving element 25 may be disposed inside the sleeve 10 in place of the thrust bearing 29. In a further modification the sleeve 10 is attached to a pillar such as 11 which is horizontally adjustable in a pillar projecting upwards from the slide 6. The spindle 14 may be driven by a pawl and ratchet crank, instead of the handle 26, or by an electric motor, and the machine may be left in position on a rail whilst trains are passing over. Lubricating cutting-tools and work.-A tank 30 of lubricant may be secured to the sleeve 10 by a clamp 31 to supply the cutter 16 through an angularly adjustable pipe 33. Drills and cutters.-The cutter 16 is hollow, so as to remove a disc from the work, and has few teeth separated by large gaps to allow free escape for cuttings. Each of the axial faces 17<1> of the teeth is inclined to a radius so as to direct the cuttings outwardly, and the cutter is mounted on the tapered end of the spindle 14 and is driven by a pin 18.