GB1085351A - Improvements in cylindrical grinding machines - Google Patents

Abstract

1,085,351. Grinding. A. A. JONES & SHIPMAN Ltd., and J. HOULDSWORTH. Nov. 20, 1964 [Aug. 21, 1963], No. 33015/63. Heading B3D. A grinding machine comprises a wheelhead carrying a rotatable grinding wheel and workpiece-supporting means for supporting and rotating a workpiece, the wheelhead or the workpiece-supporting means being mounted on a support reciprocable longitudinally on the base frame of the machine, the support having two slideways which run on two corresponding slideways on the base frame, one of the slideways on the support and its corresponding slideway on the base frame being flat, whereas the other two corresponding slideways are such as to locate the support against transverse movement relatively to the base frame; the machine is characterized in that the workpiecesupporting means, the slideways and the grinding wheel are so arranged that the axis of a mounted workpiece, the complementary slideways, the flat slideways and the axis of the wheel are generally in lateral alignment whereby any rocking movement of the support about one or the other set of corresponding slideways produces only negligible relative movement between the workpiece and the grinding wheel in the plane containing the axes of the latter. A workpiece 1, Fig. 3, is rotatably mounted between centres carried by a headstock 2 and a tailstock adjustably secured to a frame 4 angularly adjustable about a vertical joist on a support 5 reciprocated to traverse the workpiece past a grinding wheel 7. The support 5 has a flat way 10 and a vee way 9 running respectively on a flat way 10a and a vee way 9a on the base frame. The axis 12 of the grinding wheel 7, the axis 11 of the workpiece 1 and an axis x extending longitudinally of the vee ways 9, 9a lie in a plane P, which is preferably horizontal; the plane of contact of the flat ways 10, 10a is coincident with the plane P. The axis x is the line of intersection of the centre plane s, Fig. 4, of the way 9 with a plane at right-angles to, and passing through the midpoint v of, a plane y joining one of the upper corners of the way and the corner defined by the opposed inclined side and the chamfer. With the foregoing arrangement, imperfections of the flat and vee ways in elevation produce negligible relative movement between the workpiece and the grinding wheel in the horizontal direction. The only imperfection of the ways having an appreciable effect on the workpiece diameter is that of the vee ways in plan, and as this is now isolated from the other two imprefections it can be more readily corrected. To compensate for imperfections of the vee ways in plan and/or the bending of a long slender workpiece by the grinding wheel pressure, means are provided for bending the vee way 9a on the base frame. Strapping members 13, Fig. 5, are secured at 14 to the sides of the way. Each member 13 carries a cylinder 15 in which is a plunger 16 the outer end of which bears against the side of the way 9a. Regulation of the fluid pressure supplied to the cylinders produces different pressures on the sides of the way so as to bend the latter in one or other transverse direction to effect the necessary compensation. The way may be bent to such an extent that a workpiece of convex or concave shape is produced. The bending may be manually controlled or controlled automatically by means gauging the workpiece during grinding.