CONTROL SYSTEM OF HYDRAULIC CONSTRUCTION MACHINERY

摘要

PURPOSE:To maximize the absorption horsepower and output of a pump by providing a setter by which the revolving number of a prime mover is regulated to a volume suitable for heavy loads in response to detection signals and the capacity of an oil- pressure pump is controlled to a volume smaller than a preset maximum push-off capacity. CONSTITUTION:The oil pressure controller of an oil-pressure shovel is provided with a variable capacity type oil-pressure pump 13 to be driven by a prime mover, an actuator 19 to be driven by the oil pressure from the pump, and a revolving number controller 25 to control the revolving number of the prime mover. Also, a revolving number sensor 31 to send out detection signals when revolving number suitable for light load of the prime mover is exceeded is provided, and a maximum push-off capacity setter 21 to control an oil-pressure pump 13 to a push-off capacity smaller than a preset max. push-off capacity in response to the detection signals is also provided. Furthermore, a revolving number controller 25 is provided to switch the revolving number of the prime mover to a value suitable for a load heavier than revolving number suitable for light load in response to detection signals. The revolving number of the prime move can thus be controlled without changing the speeds of operations during traveling.