GB702478A - Improvements relating to a machine for cutting external splines - Google Patents

Abstract

702,478. Planing. NUFFIELD TOOLS & GAUGES, Ltd. Aug. 1, 1952 [May 23, 1951 ; Sept. 5. 1951 ; Sept. 25, 1951], Nos. 12026/51, 20932/51 and 22371/51. Class 83 (3) A machine for cutting external splines comprises means for relatively reciprocating the work and a set of pivotally-mounted form tools 5 to which an intermittent feed is imparted by an annular cam-plate 10 advanced at each idle stroke by a ratchet wheel 15, and means 25 for moving the tools simultaneously at the end of each cutting stroke to form a radius on the work. The work (not shown) is held at one end by a spring-pressed centre 1 and is reciprocated by a crank mechanism (not shown). The latter is driven concurrently with a cam mechanism which, through a push-rod 25, pivoted arms 21, a rod 19 and a lever 18, intermittently depresses a plunger 17 to advance the ratchet wheel 15. The ratchet rotates a worm 13 meshing with a wormwheel 12 carrying the cam-ring 10 which feeds the six tool-slides 7 against the pressure of springs 57. The tools 5 are adjustable initially by screws 6.' The radius at the end of each spline is cut by depressing the cutters through a sleeve 35 and bearing 38, the sleeve being moved by the rod 25. When the final cut has been taken, one of six projections 52 on the wormwheel 12 contacts a plunger 53 to withdraw a locking plunger 59 from a disc 61 and to actuate a microswitch 56 and stop the machine. The disc 61 carries a pin 64 engageable with a pin 65 on a lever 66 and is turned by a handle 63 to rotate the wormwheel 12 and position the tools so that they will take a set cut when the machine is again started. The depth of the initial cut is determined by releasing a plunger 67 from a toothed wheel 69 and re-engaging it in a new position. Dash-pots.-The movement of the cutters is damped by a dash-pot 47. Cooling and lubricating tools and work.- Coolant is supplied through an inlet 36 to the interior of the sleeve 35 and passages in a bush 33. According to the Provisional Specification 12026/51, the tools may be moved to cut the radius by pins projecting from the machine bed. Each tool is then held in its relieved position, according to Provisional Specification 20932/51, by a spring and fibre-disc friction-brake until it is positively returned to the cutting position at the end of the idle stroke. According to Provisional Specification 22371/51, the tools may be moved to cut the radius by a hydraulicallyoperated piston.