Patent GB-658278-A (GB)
Title: Improvements in or relating to devices for connecting tool heads to flexible shafts
IPC: B24B27/027
Filed: 1948-05-31
Abstract: 658,278. Grinding SANDERS, G. W.. and HAWKER AIRCRAFT, Ltd. May 31, 1948, No. 14668. [Class 60] [Also in Group XXIV] A device for connecting different tools or tool heads to the end of a flexible driving shaft comprises two interfitting sleeves 1, 2. The sleeve 1 is connected to the outer casing 3 of a flexible shaft 4. On one end of sleeve 1 is screwed a knurled connector ring 5 within the outer end of which is screwed a connector check ring 6 abutting the end of the outer casing 3 of the flexible shaft 4. Check ring 6 embraces a sleeve 7 forming an extension of casing 3 and having a flanged end 8 lying against an interned shoulder 9 formed by annular flange 10 within connector ring 5. Annular flange 10 forms a mounting for a ball bearing 11 for terminal spindle 12 secured to the end of the inner core of flexible shaft 4. The free end of spindle 12 has a screwed spigot 13 by which one plate 14 of a clutch is secured to shaft 4. A tool spindle 15 is journalled in ball or roller bearings 16, 17 at opposite ends of sleeve 2. Bearing 16 is secured within enlarged end 18 of sleeve 2 by end cover 19 carrying oil seal 20. A tubular distance piece 21 is interposed between the bearings 16, 17 the tool spindle 15 projecting through distance piece 21 and end cover 19. The inner end of tool spindle 15 terminates in a stepped spigot comprising a plain journal 22 made as a snug fit in the inner race of bearing 17 and a screwed portion 23 making threaded engagement with the sleeve 24 of an abutment plate 25 against which presses one end of clutch compression spring 26. A second clutch plate 27 has a sleeve 28 slidably supported on a sleeve 28a on the inner extremity of spindle 15 or on an extension secured to the spigot end thereof, suitable means being provided to prevent rotation of the sleeve 28 relatively to the sleeve 28a. The spring 26 forces the clutch plate 27 resiliently into engagement with the complementary plate 14 secured to the terminal spindle 13 of the flexible shaft 4 when the housing parts 1, 2 are interconnected. The clutch elements 14, 27 are constructed so as to permit slip to take place between them so that they are disengaged if undue stresses are imposed. Pressure of spring 26 reacts indirectly against a connection which secures the two main parts of the hand pieces together, this connection consisting of radial projections, e.g. pins 29 on sleeve 2 which engage bayonet slots 30 in sleeve 1. The outer end of sleeve 1 is externally threaded to receive locking ring 31 which, after engagement of the housing parts, is screwed axially outwardly to abut hard against a shoulder 32 on sleeve 2. The outer end of tool spindle 15 has screwthreaded spigot 33 for securing thereto a tool head. For holding a grinding wheel head, the tool spindle 15 may alternatively have a tapered socket to receive an arbor extending from the grinding wheel 36 having mounting means which may be in screw-threaded locking engagement with the screwed portion of the tool spindle. A guard 38 for the grinding wheel 36 is mounted on a cylindrical portion 37 on the outer end of sleeve 18. For the connection of small tools to the spindle 15, the latter has a collet screwed on to its outer end which is enclosed by a nosepiece screwed on to the outer end of the second housing part, e.g. on the projecting portion of the end cover 19 screwed into the end of the sleeve 18. The edge of the connector ring 5 may be rolled or spun into an annular groove in the sleeve 7. Specification 270,789, [Class 60], is referred to.