Patent GB-1042664-A (GB)
Title: Apparatus for taking dimensional readings in an internal grinder
IPC: B24B49/04
Filed: 1964-03-26
Abstract: 1,042,664. Grinding. J.-P. GIRARDIER. March 26, 1964, No. 12926/64. Heading B3D. [Also in Division G1] Apparatus for taking dimensional readings in an internal grinder comprises a support mounted for displacement, on the one hand, in a direction parallel to the axis of the work spindle of the grinder and, on the other hand, radially of this axis, in order to permit the positioning and removal of the workpiece to be ground, a pair of levers each mounted for pivoted movement about an axis parallel with the axis of the work spindle of the grinder, a feeler element at one end of each of such levers, these feeler elements being adapted to contact an internal bore in the workpiece at diametrically opposed points thereof during grinding, and means for resiliently urging apart the ends of the levers carrying the feeler elements in order to maintain such feeler elements in contact with the bore, whereby the spacing between the levers at the ends thereof remote from the feeler elements is dependent on the dimension of such bore, and means whereby such spacing is utilized to furnish, during grinding, the desired information as to the dimension of the bore. A slide 8, Figs. 1 and 2, movable parallel to the work spindle 2 carries a transversely movable slide 9 on which slides 10, 11 are adjustable towards and away from each other by a screw 12. Levers 15, 16 pivoted on the slides 10, 11 have at their inner ends feeler elements each comprising a cylindrical segment 19 with a longitudinal protuberance 19a for contacting the bore of the workpiece 4; the end carrying the feeler element may be exchangeable. The inner ends of the levers 15, 16 are urged apart by a spring 17. The outer end of the lever 15 carries a dial gauge 20 the feeler 21 of which contacts the outer end of the lever 16. When the dial gauge indicates the desired bore diameter, the machine is stopped; the stopping may be effected automatically by the gauging device and the dial gauge omitted. The movements of the slides 8, 9 to move the gauging device between a retracted position permitting mounting of the workpiece and an operative position are effected hydraulically. The feeler elements are moved towards each other by pistons in a cylinder 22. In a modification, Fig. 4, each feeler element has two protuberances 23a, 23b, the protuberance 23a on either element being diametrically opposite the protuberance 23b on the other element. In another embodiment, Figs. 5, 6 and 8, a frame 26 mounted on an internal grinder so as to be movable in two directions perpendicular to one another supports a slide 28 displaceable in the direction of the arrow 29. The slide 28 carries two guide columns 32 on which are movable two slides 33. Two levers 34 pivoted on the slides 33 by double row ball bearings 39 have secured to their inner ends feelers 35 with feeler elements 36. The slides 33 are urged towards each other by springs 42, their spacing being determined by the engagement of lugs 47 on the slides 33 with a wedge portion 43a on a member 43 guided longitudinally by engaging grooves 44 in the columns 32. The member 43 is adjusted by a screw 48 rotatably mounted therein and in screwthreaded engagement with one column 32. The screw 48 has a polygonal extension 48a slidably engaging a wheel 49 rotatable in a part 26a which clamps the frame 26. A member 50 pivoted on the member 43 has at its rear end a wedge portion 50a, the surfaces of which have the same slope as the surfaces of the wedge portion 43a and which co-operate with lugs 52, 53 carried respectively by the levers 34. A spring 55 holds the wedge portion 50a and lug 52 in contact. During longitudinal movement of the member 43 to alter the spacing of the slides 33, the wedge portion 50a acts on the lugs 52, 53 to prevent relative displacement between the levers 34 and the slides 33, so that during initial adjustment to suit the bore diameter to be gauged the levers 34 move parallel with themselves without affecting the gauge reading. After the initial adjustment the spacing of the levers 34 varies as the bore diameter alters, so varying the gap between the wedge portion 50a and the lug 53. The latter has an axial bore 54 communicating with a passage 41 in the lever 34 which carries it and leading to a conduit 40 to which is connected by fitting 39a a flexible conduit leading to a pneumatic gauge. The feeler elements 36 are moved towards each other for removal from the bore by cylinders 57 acting on the rear ends of the levers 34. The slides 33 are clamped in adjusted position by plates 58, 59 forced together by a screw 61.