Patent ID: 7958693
Filing Date: 2011-06-14
Classification: E02F

Abstract:
1. A boom for a working machine attached to an upper rotational body supported on a center of an upper portion of a traveling device to be transversely rotatable, the boom comprising: a boom support point part; a boom cylinder rod support point part having a first opening portion and a second opening portion, the second opening portion being oriented at an oblique angle with respect to the first opening portion; an arm support point part; and first and second straight parts having said boom cylinder rod support point part therebetween; and an arm cylinder bottom support point provided at a convex portion projecting from a rear surface of said boom cylinder rod support point part, wherein: each of said first and second straight parts has a rectangular cross section of constant transverse and longitudinal dimensions over an entire length, said first straight part is connected at one end thereof to said boom support point part, and at the other end thereof to said first opening portion of said boom cylinder rod support point part, and said second straight part is connected at one end thereof to said arm support point part, and at the other end thereof to said second opening portion of said boom cylinder rod support point part.