GB896241A - Rotary polishing element - Google Patents

Abstract

896,241. Abrasive wheels. CODMAN CO., F. L. & J. C. July 21, 1958 [July 26, 1957], No. 23391/58. Class 60. A polishing element comprises a multiplicity of spaced strips 26, Fig. 1, secured at their inner ends to the slots in the periphery of a central disc 20, each finger being of abrasively-coated woven fabric with its weave extending along the length of the strips such that when abrasive material is worn away over the outer ends of the strips, the transversely extending threads within those regions become readily detached. The strips 26 are cut from two tapes T, Fig. 8, which may be of emery cloth and have longitudinal warp threads stronger and more numerous per unit length than the weft threads. The tapes are placed with their abrasive coatings facing each other and the longitudinal edges 44 are adhered together by an adhesive, such as rubber latex, from rollers 42. When the strips are cut, the weft is parallel to the longitudinal direction of the strips and the plies tend to curve, except at the ends which are adhered together, in the direction of the warp, as shown in Fig. 9. The strips are adhered to the disc 20 in slots 24, Figs. 1 and 3, arranged diagonally to the axis of the disc and inclined to the radius thereof, the disc being of a fibre board or like material. The strips are wider than the thickness of the disc and portions 28 of the ends are bent over in the same or opposite directions and adhered to the sides of the disc. The wheel may be assembled by placing a cover disc 30, Fig. 10, which may be of dense fibrous material, on a rod 52 upstanding from a base plate 50 and resting the disc 20 on a support 54 which can be radially moved into and out of position and has an extension 60 serving as a gauge to position the strips. The ends of the strips are dipped in adhesive and fitted into the slots and, upon removal of the support 54, the lower and an upper cover plate 30 adhered to the sides of the disc and the bent-over portions 28 of the strips; a further pressing may be carried out on another machine. The assembled wheel then has its edge trued to remove the adhesive at the outer ends of the strips and may -be used on its own or with a plurality of wheels; in the latter case, alternate wheels are reversed, the strips, being wider than the discs, nestling with one another. Specification 873,200 is referred to.