Patent GB-1122483-A (GB)
Title: Tilted spindle grinder
IPC: B24B7/00
Filed: 1965-12-15
Abstract: 1,122,483. Grinding. E. W. BLISS CO. 15 Dec., 1965 [27 Jan., 1965], No. 53226/65. Heading B3D.  Apparatus for grinding steel billets or slabs to remove scale or imperfections therefrom comprises a support head 58 arranged for movement towards and from and longitudinal traverse relative to the surface of a workpiece 14 from which a uniform thickness of material is to be removed, a grinder spindle 50 resiliently mounted in the support head with its axis of rotation 57 tilted at an acute angle to the work surface, and a servo control responsive to changes in the contour of the work surface for causing the advance and retraction of the support head. The grinding spindle is provided with four brackets 56 having rollers engaging surfaces on the support head 58 which has a plate 65 carrying an electric motor 55 connected to the grinding spindle by a ball spline shaft 52 and spline nut 54. The spindle, which supports a grinding-wheel 12, is resiliently supported from a plate 74 of the head by rods around which are calibrated coil springs 72. A selsyn transmitter 86 is mounted on plate 74 and connected by a link 87 to the grinding spindle so as to produce an output voltage upon movement of the grinding spindle relative to the support head. The output voltage is fed to a magnetic amplifier of the servo control to a motor 82 which, through bevel gears 84 and ball nut and screw mechanisms 83 causes vertical movement of the support head 58 in a tilted support head 40 to maintain the pressure between the grinding-wheel 12 and workpiece constant, the support head 58 being guided for movement in the tilted support head by means of rollers 62. The tilted support head 40 is mounted on pivots 42 in a support 30 and is movable to one or other of positions on either side of the vertical by cylinders 44 according to the direction of relative movement between the grinding wheel and workpiece. The support 30 is carried by rails 32 and bogies 34 between frame members 18 which extend between uprights 20 of a main frame 10, the support being indexably movable transversely of the direction of grind by ball nut and screw mechanisms 35 driven by chains 37 from a reversible motor 36. The main frame is provided with rollers 22 engaging rails 24 for movement in the direction of grinding by means of synchronized drive units 25 having motors 26 connected through reduction gearing 27 to the rollers. Alternatively, the workpiece may be reciprocated relative to the grinding wheel. In operation, once a predetermined grinding pressure has been established, the output from the transmitter is balanced against a reference signal and any variation in the output acts on the motor 82 to raise or lower the grinding wheel to restore the balance and maintain the grinding pressure constant. In an alternative embodiment, Fig. 6 (not shown), the transmitter 86<SP>1</SP> is not responsive to the pressure on the grinding wheel but is actuated by a feeler 110 which senses the contour of the workpiece in front of the grinding wheel to adjust the motor 82<SP>1</SP> so that the grinding wheel removes a constant depth of material.