Abstract: A bulldozer apparatus for a working vehicle comprising a vertically pivotable arm assembly, and a blade pivotable on a fore and aft axis extending along a center position of the vehicle. Two hydraulic cylinders are disposed at opposite sides of the fore and aft axis for causing pivotal movement of the blade such that the blade is pivotable in opposite directions with extensions of the hydraulic cylinders. Two engaging devices extend substantially longitudinally of the vehicle at opposite positions across the fore and aft axis and interconnect the blade and the arm assembly for relative pivotal movement.

Abstract: A hydraulic circuitry for a backhoe in which a hydraulic motor for driving one of right and left crawlers and a hydraulic cylinder for vertically oscillating a working arm assembly are connected in parallel to each other to a first pump through a multiplex valve assembly having a first center bypass, and a hydraulic motor for driving the other crawler, a hydraulic motor for slewing a platform, a hydraulic cylinder for flexing and stretching the arm assembly, a cylinder for actuating a bucket and a cylinder for actuating a dozer are connected in parallel to one another to a second pump through a further multiplex valve assembly having a second center bypass. The invention provides a circuit to permit fluid pressure from the first pump to enter the circuit connected to the second pump to provide confluence therein, when the dozer actuating cylinder connected to the second pump, for example, is operated while the backhoe is running.