Patent GB-1430884-A (GB)
Title: Radiusing dressing device
IPC: B24B53/12
Filed: 1974-04-26
Abstract: 1430884 Dressing grinding wheels SOC NOUVELLE DE ROULEMENTS 26 April 1974 [10 July 1973] 18516/74 Heading B3D A device for dressing a part toroidal form on the periphery of a grinding wheel comprises means 4 for oscillating a spindle 3, without backlash, through a limited angle about an axis XY in an outer portion 1, a support 46 secured to the outer portion by a first mount 45 which is deformable in a first direction perpendicular to the axis XY and has a high rigidity in a second direction perpendicular to the first, and a diamond carrier 27 secured to the end of the spindle 3 by a second mount 26 which is deformable in one direction and has a high rigidity in a perpendicular direction, each of the mounts having adjustment means to deform the mounts, deformation of the first mount adjusting the outer portion relative to the support in a direction perpendicular to the axis, and deformation of the second mount adjusting the diamond carrier with respect to the axis. The two adjustments permit for correction in the alteration of the diameter of the grinding wheel and alteration in the radius of curvature of the toroidal form, the grinding wheel being used to grind bearing races. The spindle 3 is hollow and supported in pre-loaded angular contact bearings 2 in the outer support 1. The means 4 for oscillating the spindle so that a diamond in a mount 28 forms the part toroidal form on the grinding wheel consists of an hydraulic motor having a cylinder 9 which is secured to the support 1 and has a stationary quadrant 8, and a piston 5, in the form of a quadrant, secured to the spindle, the angular movement of the piston and spindle being determined by engagement of a finger 19 on the spindle with adjustable limit stops 16, 17; proximity detectors (21, 22, Fig. 2, not shown) are actuated by the finger to operate valves controlling fluid flow to the cylinder. A plate 25 is secured by a centring sleeve 23 to the end of the hollow spindle 3, and the mount 26, which is a wide parallelepiped having two arms 26b, 26c joined by a thinner portion 26a so as to be deformable in the direction of the axis XY but rigid in a transverse direction, has one arm 26c secured to the plate 25 and the other arm 26b secured to the carrier 22 for the diamond mount 28. A lever 34 is mounted on a pivot 36 in a recess in plate 25, and intermediate its length, has an abutment 37 engaging a further abutment 38 which is secured to arm 26b and extends with clearance through arm 26c whereby movement of the lever 34 causes deformation of the mount 26 about the thin portion 26a so that the carrier 27 is rocked to move the diamond towards or away from the axis XY of the spindle to correct any alteration in the radius of curvature of the part-toroidal form. Movement of the lever is effected by rotation of a differential screw mechanism 31, 33 which has an abutment 33c engaging the end 34a of the lever and is disposed within the hollow spindle 3 and rotated by a graduated knob 32. The second mount 45 is similar to the first and has a relatively thin portion 45a between two arms 45b, 45c secured to the support 46 for the apparatus and the casing 9 of the hydraulic motor, respectively. Deformation of the second mount 45 about the thin portion 45a is effected by a differential screw mechanism 56, 58 between the support 46 and outer portion 1 to adjust the outer portion 1 and spindle 3 transversely to the axis XY of the spindle and hence to adjust the diamond to correct for alteration in the diameter of the grinding wheel. Approximate adjustment of the apparatus to the workpiece diameter and the radius of the part-toroidal form are made by lateral (i.e. vertical in Fig. 1) adjustment of the support 46 and adjustment of the carrier 27 on the mount 25, respectively. The manual operation of the differential screws may be replaced by step-bystep motors.