| 摘要 |
Fastener intended for canvas comprising a sleeve (10) with a tubular portion (11) which is intended to extend through a hole in the canvas material (22), also a flange portion (12,24) on each side of the material. Between these flange portions there is canvas material with an area around the said hole where a ring-shaped surface is arranged to press against the surface of the material so that a friction connection is formed. The surface, which is preferably located on a separate ring (1), is provided with projections which are arranged to be pressed into the material (22) under the influence of the force from the flange portions so that the positive connection is furthermore formed. A supporting ring (17) is arranged to be present on the opposite side of the material (22) as related to the surface provided with projections. The supporting ring is made from a material which has such a hardness as compared with the material in the projections that it can be inserted in the ring thus providing an anchorage for the outer portions of the projections. |
