| 摘要 |
1,229,191. Trueing grinding wheels. COVENTRY GAUGE & TOOL CO. Ltd. 17 May, 1968 [18 Feb., 1967], No. 7831/64. Heading B3D. [Also in Division F2] Apparatus for dressing a helically-ribbed grinding wheel 3 comprises a pair of dressing tools 2 traversible together in timed relation with rotation of the grinding wheel whereby the dressing tools enter between the flanks of the wheel rib form and are traversed back and forth across the rib form in dressing contact with corresponding rib flanks in at least one direction of the traversing movement, and means for imparting incremental feed to the dressing tools after each traverse in order to progressively advance the tools radially in relation to the rib flanks. Each tool 2, which may be a diamond dressing tool, is carried by a slide 6 movable along an inclined slideway 7 on a carrier slide 9, the latter slides being movable along a slideway 9a on a dresser head 1. An arm 15 is mounted on a pivot 16a on each slide 9 and at one end has a nose 17a engaging an adjustable screw 19 on its associated slide 6 and at the other end has a nose 15a engaging a surface 14 parallel to the axis of the grinding wheel 3 on a slide 10 vertically movable by a screw 11. Each screw has a pulley 12 and the pulleys are interconnected by a toothed belt 13 engaged by a pawl 22 actuated by an hydraulic piston-andcylinder device 21. The device is operated at each traverse of the dressing head 1 to cause the screws 11 to move the slides 10 and, via the arms 15, the slides 6 so as to provide an incremental feed of the tools. On the return traverse, an hydraulic device 23 operated in conjunction with the device 21 moves the slides 9 so that the tools are withdrawn from engagement with the grinding wheel. Variation of the form dressed on the rib flanks may be provided by a cam surface 31 on each slide engaged by a lever 32 mounted on a pivot 33 on the head 1. An eccentric pin 35 on each lever co-operates with an adjustable follower 36 on each slide 9 so as to superimpose an additional movement on the slide 9 as the slides 10 move vertically. The dresser head 1 is vertically adjustable on a carriage 42, Fig. 3, by an hydraulic piston-and-cylinder device 43 or a screw 44, and the carriage is reciprocable along a roller slide 46 on a base 47 to traverse the dressing head by a screw 27 which engages a nut 28 and is connected by gearing 29 to the means for rotating the grinding wheel so that the latter is rotated in timed relation to the traverse of the dressing head. The traverse of the dressing head may be modified by advancing or retarding the lead-screw during traverse of the head by means of a cam in the form of a sine bar 62, Fig. 2, engaging a follower 64 on a slide 65 slidable on the base member 47. The slide 65 is connected to a flexible band 67 passing round a member 69 on the lead-screw and connected to a spring. The member co-operates with a nut on the screw so that as the member is moved by the band, the screw is advanced or retracted axially to modify the traverse of the head caused by rotation of the screw (see Division F2). |
