| 摘要 |
An open-end wrench (10) is disclosed which can be used with a variety of fastener head shapes and which reduces marring or round-off of the corners of the fastener head (17). The wrench has a wrench cavity (16) for receiving the fastener (17). The wrench cavity (16) includes convex drive surfaces (21) which have a radius of curvature equal to half of the faster head width (A). Clearance surfaces (22, 24) are provided adjacent the drive surfaces (21) to accept the corners of the fastener head (17) when force is applied to turn the fastener (17). |
