GB311489A - Improvements relating to grinding or abrading machines - Google Patents

Abstract

311,489. Hughes, V. A. B., (Cincinnati Grinders, Inc.). Feb. 29, 1928. Centreless grinding; wheels.-A grinding- machine wherein the work is positively rotated about a definite axis located therein during grinding, comprises grinding and regulating wheel and pivotally mounted centres for supporting the work between the wheels so that the axis of the work may move away from the regulating wheel and have a. component along the operative surface of the grinding wheel when the regulating wheel engages a protuberance on its surface. The machine comprises a bed 10 provided with ways 12, Fig. 2, on which slides a saddle 13 having arcuate guides 14, Fig. 1, at its ends to support a. table 16. A headstock 17 and tailstock 18 are adjustable along the table 16, the former carrying a spindle 20, face-plate 23 and live centre 24 driven by a belt pulley 21 and the latter a dead centre 26 adjusted by a screw 27. A bracket 39, adjustably secured on the table 16 by a bolt 41, carries a pivot bar 43 on which are mounted two brackets 46, 54, each carrying centres 48, 51 to support. cylindrical work pieces such as bolts 53. The work is rotated and pressed against the grinding wheel 33 by a regulating wheel 65 carried by an arbor 62 mounted beween the head and tailstocks and rotated by a driver 63. A second regulating wheel 64, Fig. 1, coacts with a second workpiece 61, the arrangement being such that as the table 16 is reciprocated past the grinding wheel, one work-piece is being operated upon whilst the other is being changed. The grinding wheel is carried by a shaft 32 mounted in bearings 31 on a carriage 30 adjustable along guides 28 transversely of the line of movement of the table 16. The grinding wheel is rotated by a belt 34, the direction of rotation of this wheel and the regulating wheels being as shown by the arrows in Figs. 1 and 2. The regulating wheels are built up of a number of discs so that their lengths may be adjusted to suit the length of the work. A sleeve 62<c>, Fig. 1, spaces the regulating wheels the correct distance apart, on the arbor 62 and the wheels are secured on the arbor by a nut 62b coacting with a flange 62<a>. The axis of the work 53, Fig. 2, is arranged at a point of front of the vertical plane passing through the axis of the pivot 43 so that if a projection on the work engages the regulating wheel, the work will be displaced in an upward direction towards a more remote portion of the grinding wheel with the result that the movement of axis of the work has a component along the operative surface of the grinding wheel as well as towards it. Adjustable screw stops 66 on the brackets 46, 54 limit the movement of the brackets away from the grinding wheel whilst the work is being changed. The centres 48 are secured by screws 49, Fig. 3, and the centres 51 by thumb-screws 52 to facilitate removal of the work. For normal centre grinding the arbor 62 and bracket 39 are removed and the work is mounted between the centres 24, 26, the table 16 being reciprocated past the grinding wheel and being adjusted to produce cylindrical or tapered work. A guard 36. Figs. 1 and 2, is provided over the belt pulley 35 for the grinding wheel and means may be provided for trueing the grinding aud regulating wheels.