Patent GB-849707-A (GB)
Title: Abrading machine
IPC: B24B27/00
Filed: 1958-08-08
Abstract: 849,707. Grinding. SUNBEAM CORPORATION. Aug. 8, 1958 [Sept. 6, 1957], No. 25549/58. Class 60. An abrading machine comprises a housing having a pair of horizontally aligned bearings mounted'in a pair of bearing openings in a pair of opposed walls of the housing, a drive shaft carrying abrading means being journalled in the bearings and drivingly connected to a motor unit removably mounted in the housing laterally of the drive shaft which is drivingly connected with a honing shaft journalled in the housing and having a honing stone mounted thereon. A grinding wheel 17 and a plate 18 for a sanding disc are mounted on the opposite ends of a shaft 11 driven at reduced speed by an electric motor 24, the shaft 11 driving the shaft 55 of a honing disc 63. A light-weight high-powered heavy-duty series-wound motor 24 has slotted mounting brackets 28 secured by screws 29 to posts 31 integral with the top wall of a one-piece cast housing 10, e.g. of die-cast aluminium. Moulded rubber feet 141 are mounted in openings in the corners of the housing 10 ; a fan is associated with the motor, and air openings 36 are provided in a bottom cover plate 35 secured by screws 37 to posts 38 integral with the housing. Connections between the motor 24, a switch 151, and a supply cable 160 are made by connectors 156, 157 which are unscrewed when the motor is to be removed from the housing. A toothed pulley 22 on the armature shaft of the motor is connected by a toothed belt 21 to a larger toothed pulley 19 secured on the shaft 11 by a pin 20. The shaft 11 runs in porous bronze bushings 12, 13 press fitted in line reamed journals 14, 15 formed in the housing 10; the bushings are lubricated by wicks 173 in holes 171, 172. The shaft 11 passes through neoprene grommets 43 in aligned bores in a part 41 integral with the housing 10. A worm 57 on the shaft 11 meshes with a worm-wheel 56 on a shaft 55 running in a sintered bronze bearing 47 having a flange 48 secured by screws 49 to an annular portion 51 of the part 41. The lower region of the part 41 is filled with grease to lubricate the worm gearing, a cover 52 being held between the flange 48 and annular portion 51. A cup 61 having a sleeve 62 keyed to the shaft 55 carries a honing stone 63 with an interposed felt pad 64, holes 58, 59 in the pad and cup permitting access to the screws 49 which retain the bearing 47. Articles being honed are supported by a rod 71 mounted in a boss 72 and clamped in adjusted position by a set screw 73. The grinding wheel 17 is secured on one end of the shaft 11 by a nut 86 with washer 83 and a flanged sleeve 82 having notches 85 engaging a pin 84 on the shaft 11. A guard 88 is secured by screws 89 to the housing 10. A tool rest 94, having a lip 97 to prevent tools being accidentally introduced between the grinding wheel and the rest, is adjustably mounted by bolt 95 and slot 96 on a bracket 92 secured by screws 93 to the housing 10. A transparent guard 110 is mounted in a frame 102 connected to a post 104 pivotally secured to the guard 88 by a bolt 103. The other end of the shaft 11 has threads 112 engaging a topped bore 115 in the sanding plate 18, to the end face 119 of which a sandpaper disc is attached by glue or by pressure sensitive adhesive. A guard 125 is secured to the housing 10 by screws 126. A work rest 130 has slots engaging screws 134 in bosses 135 formed in the housing 10.