Patent GB-859767-A (GB)
Title: Truing mechanism for grinding machine
IPC: B24B53/08
Filed: 1959-09-10
Abstract: 859,767. Trueing grinding and regulating wheels. CINCINNATI MILLING MACHINE CO. Sept. 10, 1959 [Feb. 26, 1959], No. 30903/59. Class 60. Mechanism for trueing grinding wheels generally and the regulating wheels of centreless grinding machines comprises a cutter-carrying member which, as it is traversed across the edge of the wheel, is caused to move to and from the wheel by the action of a follower bar which is pivoted to the member and engages guide surfaces disposed on opposite sides of the pivot of the bar. The grinding wheel 17, Figs. 4 and 6, is trued by a diamond 141 carried by a bar 139 axially adjustable in a sleeve 136 which is itself axially movable (under the action of a follower 152) in a slide 132 carried by an adjustably-swivelled support plate 130 ; the bar 139 is adjustable in the sleeve 136 by a manually-operable lead screw 143 and the slide 132 is reciprocated by a lead screw 133 operated by an hydraulic motor 134. The follower bar 152 is pivoted at its mid-point 150 to a clevis 151 depending from the sleeve 136 and is spring- urged so that pivoted shoes 153, 154 on its ends slidably engage control surfaces 161a, 162a on two guide bars 161, 162 adjustably carried by a bracket 155 on the support plate 130. The bars 161, 162 are set in their desired control positions by pivoting them about bolts 159 under the control of set-screws 166 and clamping them in adjusted positions by bolts 160. As applied to the trueing of the regulating wheel 24, Figs. 8 and 10, a diamond 46 is mounted at the lower end of a bar 45 carried by a sleeve 44 axially movable in a slide 40, which, by means of a lead screw 42 and hydraulic motor 43, is traversed parallel to the axis of the regulating wheel in a support 30 adjustably swivelled in a housing 23 ; the bar 45 is adjustable axially in the sleeve 44 by a screw 49 operated by a lever 57. The sleeve 44 is guided for axial movement in the slide between roller tracks, being urged downwardly by springs 72 so that, as the slide is traversed by the motor 43, guide shoes 88, 90 pivoted at the ends of a follower bar 86, which is pivoted at its mid-point 84 to a clevis 85 on the sleeve, engage slidably with control surfaces 104a, 105a on guide bars 104, 105 carried by a bracket 91 on the support 30. The guide bars are arranged to be set in desired angular relation to produce a given contour on the wheel 24 by connecting their inner ends to coaxial discs 101 rotatable in plates 100 on the bracket 91 and providing between the bars and a second plate 112 adjustably mounted on the bracket 91 an adjustable connection in the form of set screws 124 and bolts 118 engaging slots 118a" In both the above constructions, the use of one continuous control surface on each guide bar produces a continuous arcuate formation on the wheel. If desired, however, each guide bar can have two straight, but relatively inclined, control surfaces so that a different curve is produced when the ends of the follower bar engage the two inner control surfaces of both bars at one portion of the traverse from that produced at another portion of the traverse when the inner control surface of one bar and outer control surface of. the other bar are simultaneously engaged. Unsymmetrical profiles may also be produced by arranging for the traverse to be other than parallel to the axis of the wheel, inclining the two guide bars at unequal angles to such traverse, displacing the pivot between the sleeve and follower bar from the mid-point of the latter, and displacing the diamond from the position shown. A centreless grinding machine is described in which, in order to produce barrel-shaped workpieces 25, Fig. 2, the grinding wheel 17 is shaped to a concave curvature and regulating wheel 24 to a convex curvature.