| 摘要 |
A composite casing 10 for a coilable rule comprises a pair of inner, plastic case members 20, 22 and a thin, outer metal case 50, 52 which receives the plastic case members 20, 22 in a close fitting relationship. A center post 70, 100 is received in central openings 28, 38 provided in the plastic case members 20, 22 to support a measuring tape 12 and coil spring 14 of the rule. One end of the center post 70 has an enlarged head 72 and its other end receives an assembly screw 80 extending through holes in the metal case 52 to engage and hold the metal case 52 in firm assembly with the plastic case members 20, 22. A series of knurls 78 is formed on the center post 70 for engaging one of the plastic case members 20 to hold the post 70 firmly in place. Alternatively, the center post 100, Fig. 3 (not shown) may be formed as an integral part of one of the plastic case members. A plurality of deformable ribs 104, Fig. 5 (not shown) may be provided on the exterior surfaces of the plastic case members 20 to engage the metal case 50, 52 and firmly hold the assembly together. <IMAGE> |
