| 摘要 |
<p>An arm (11) for a hydraulic excavator (1) is formed as a box-type structure surrounded by left and right side plates (12, 13), a top plate (14) joined to the upper end side of each side plate (12, 13), a bottom plate (15) joined to the bottom end side of each side plate (12, 13), and a thick rear plate (16) joined to the rear end sides of each side plate (12, 13) and the top plate (14). The left side plate (12) is formed by joining two members comprising a rear thick side plate (12A) and a front thin side plate (12B). The right side plate (13) is formed by joining two members comprising a rear thick side plate (13A) and a front thin side plate (13B). The top plate (14) is formed by joining two members comprising a rear thick top plate (14A) and a front thin top plate (14B). The bottom plate (15) is formed by joining two members comprising a rear thick bottom plate (15A) and a front thin bottom plate (15B).</p> |
