Frame structure of crawler-type construction machine vehicle

The frame structure of a crawler construction machine vehicle which integrates left and right track frames and a vehicle body frame into a rigid structure, which comprises:

• the left and right track frames being parallelly arranged in a left and right direction with an interval therebetween and integrally coupled together by front and rear cross beams respectively bridging the interval between the left and right track frames,
• the vehicle body frame including left and right vehicle body frame members parallelly arranged to the left and the right track frames within a width of the interval of the left and the right track frames, the left and right vehicle body frame members including long vertical plate beams, notched portions are provided at two locations in a longitudinal direction of lower sides of the vertical plate beams, the respective notched portions are fitted to the front and the rear cross beams so that the vertical plate beams are integrally coupled to the front and the rear cross beams in an intersected shape, and portions of the left and right vehicle body frame members extending between the front side cross beam and the rear side cross beam are constituted as box beam portions;
• and
• a bottom plate member connecting an interval between lower ends of the pair of left and right vertical plate beams, and an interval between rear ends of the left and right vertical plate beams being connected by a vertical wall member in a right angle, said vertical wall member covering from upper faces of the rear ends of the left and the right vertical plate beams over to rear faces of the rear side cross beam and the left and right vehicle body frame members being rigidly joined to upper positions of the front and the rear cross beams.