GB878833A - Improvements in or relating to means for machining trochoidal rotors - Google Patents

Abstract

878,833. Grinding. NSU WERKE A.G., and WANKEL, F. June 20; 1958, No. 19882/58. Class 60. Means for producing or processing a cylindrical surface of a rotor, the cross-section of which is a trochoid or a curve parallel thereto, including two wheels rolling one against the other, one of the wheels being connected to a point which describes a trochoid on the rotor which is fixed in relation to the second wheel, a processing tool being mounted on a support rotatable about the trochoid-generating point and always being normal to the generated trochoid, the support having a slideway pivotally connected to an arm which is rotatable about a point located on a line connecting the centres of the two wheels, is characterised in that the arm, to which the slideway in respect of the tool support is pivotally connected, is rotated by a wheel the axis of rotation of which is located on the line connecting the centres of the wheels and which is rotated in the same direction- and at the same speed as the wheel bearing the point generating the trochoid. A trochoid is generated by a point P 2 on a wheel K 2 rolling on a wheel K 1 . A link n is pivoted at Pz and passes through a guide P on an arm N<SP>1</SP>I<SP>1</SP> secured to a wheel K<SP>1</SP> 2 . The points of contact of wheels K 2 and K 2 <SP>1</SP> with the wheel K 1 are at opposite ends of a diameter of wheel K 1 . The geometry of the arrangement is such that n passes through the point of contact of wheels K 1 K 2 and is thus normal to the trochoid. As exemplified in a machine, Figs. 3 and 4, the workpiece 2 is clamped to a base plate 1. A casing 4 secured to the base plate 1 carries a non-rotatable bolt 5 on which is keyed a gear 9. Arms 15, 16 rotatable about the bolt 5 by gears 27, 28 carry gears 11, 12 meshing with the gear 9.. The shaft 13 of gear 11 is formed as a swivel arm 31 in which is mounted a pivot member 32 through which passes a rod 33. The shaft 14 of gear 12 has an eccentrically arranged pivot member 34 on which is rotatably mounted a bridge 35 connected to the rod 33 by screws 36. The rod 33 has a recess 37 in which is slightly guided a support 38 for a guiding wheel 39 driven by belt 45 for a motor 46 ; the support 38 and motor 46 are adjustable relative to the rod 33 by a screw 41. In a modification, Fig. 5, the wheels K 2 and K 2 <SP>1</SP> are internally toothed and engage wheel K 1 . In a further modification, Fig. 7, a wheel K 2 * concentric with the wheel K 2 drives, through idler K 1 ,* a wheel K<SP>1</SP> 2 * which carries the guide T for the member pivoted at P 2 . The wheels K 2 may be internally toothed.