Grease feeding piping arrangement structure in construction machine

A grease feeding piping arrangement structure in a construction machine comprising:

• a working attachment being pivotally supported at a distal end portion of an arm so as to be freely swingable via a first pin shaft;
• an extensible cylinder being, at its proximal end portion, supported by the arm, configured to extend and contract so as to cause the working attachment to swing;
• a power link being, at its one end portion, pivotally supported by the working attachment so as to be freely swingable via a second pin shaft, and being, at its other end portion, pivotally supported at a distal end portion of the extensible cylinder so as to be freely swingable via a third pin shaft;
• and
• a pair of right and left idler links being, at its one end portion, pivotally supported so as to be freely swingable via the third pin shaft which pivotally supports the other end portion of the power link and the distal end portion of the extensible cylinder, and being, at its other end portion, pivotally supported on the right and left side face parts of the arm so as to be freely swingable via a fourth pin shaft,
• wherein upon arranging a grease feeding piping in the idler link, the idler link is configured to have a link body part in a flat plate shape which pin holes for the third and fourth pin shafts are formed on both end sides;
• to form a protruding part which protrudes in a direction opposite to a working attachment from the link body part by causing the link width of the link body part to extend in a direction opposite to the working attachment;
• to set up a grease feeding piping arrangement space extending in a link length direction, in a right and left inside of right and left outer side faces of the protruding part, with at least either one side of the side opposite to the working attachment or right and left inward sides open;
• and to arrange the grease feeding piping in the grease feeding piping arrangement space, in a state of not protruding in a direction opposite to the working attachment beyond a protruding distal end portion face of the protruding part and not protruding right and left inwardly beyond right and left inner side link faces of the link body part.