Patent GB-716488-A (GB)
Title: Improvements in or relating to grinding, polishing, boring and drilling apparatus
IPC: B24B3/55
Filed: 1951-03-15
Abstract: 716,488. Grinding. MERZ, F., and MERZ, D., [trading as MERZ-WERKE GEB. MERZ]. March 15, 1951 [March 15,1950; Oct. 26, 1950], No.6219/51. Class 60 [Also in Group XXII] A machine for grinding and polishing knives, the blades of mowing machines, planing machines and the like and for boring and drilling comprises a spindle 4, Fig. 1, mounted on supports 2, 3, on a base 1 so as to be displaceable in the direction of its axis and rotatable about the axis, and a motor 7 attached to the spindle 4 and having a tool 15 mounted direct on the shaft 13 of the motor, the motor being detachable for use as a hand tool. As applied to grinding the blades 16 of mowing machines, the beam 16a supporting the blades is clamped by a spring-pressed jaw 18 in a recess in a work-holder 11 which may be secured in adjusted position against the base 1 by a screw 21 received in an arcuate recess 10. The jaw 18 may be withdrawn by a knob 20 against the influence of a spring 17 to release the beam 16a. The motor 7 driving the cuptype grinding wheel 15 is clamped adjustably by nuts 8 to a plate 5 carried by the spindle 4 which bears against rollers in the supports 2, 3. A handle 12 is provided to traverse the motor; and the tool 15 is fed by a lever 14 which moves the motor armature against the influence of its magnetic field or a spring or both. As applied to surface grinding, Fig. 2, the supports 2, 3 pivot on a pin 31 fixed to the base 1 which may support the workpiece on an electromagnetic work-holder 34 or along a steel straight-edge. In a further construction for grinding the blades of mowing machines; Fig. 6, the blades 48 are supported on a platform carried by a rod secured to the work-holder 46 which is mounted to pivot about a pin 50, Fig. 5, on the cradle 39. Springs 49 press the beam of the blades against the wall of a recess 47 in the work-holder which may be adjusted about the pin 50 against the influence of a spring 52 as by a screw 51 or tooth segments. The motor 7 is mounted in a collar 41 carried by spindles 40 so as to pivot in the cradle 39. Bars 43 carried by the cradle limit the extent of rocking of the motor by engaging rollers 44 carried by diametricallyopposite lugs on the collar 41. To provide different limits of rocking thicker bars 43 may be used, or they may be located in different positions, or rollers 44 of various sizes may be used. As applied to drilling, a bar 43 may be provided on one side only of the motor..A gauging block 54 is provided for rough adjustment of the grinding wheel 15 which may be adjusted finely by means of a screw acting on the lever 14 or by finger pressure applied direct to the motor shaft. In a further modification, Fig. 8, the motor is secured by a plate 57 to a spindle 55 provided with a clamping ring 56 to limit movement. Discs 58 pivoted eccentrically on the plate 57 engage bars 61 to limit pivotal movement of the motor. The throw of the disc in the direction of the bar 61 may be. adjusted by displacing the disc against a spring 60, Fig. 9, and re-engaging a pin 59 with another of the recesses in the disc.