Patent ID: 11965406
Assignee: SOILMEC S.P.A.
Field: Civil engineering (Other fields)
Classification: CPC E  F | IPC E  F

Claim 7:
8. An excavating machine, comprising:
an actuation unit for moving an excavator:
a main winch connected, through a main line, to the actuation unit, for lifting and lowering said actuation unit;
a secondary winch connected, through at least one secondary line, to the actuation unit, for lifting and lowering said actuation unit;
a primary driving circuit, which is a closed hydraulic circuit or an electric circuit, for driving the main winch;
an open hydraulic circuit for driving the secondary winch
a first pressure sensor or a current sensor, associated with the primary driving circuit for measuring pressure of a fluid or, respectively intensity of an electric current, said fluid or said current being adapted to circulate in said primary driving circuit for driving the main winch;
a second pressure sensor associated with the open hydraulic circuit, for measuring pressure of a fluid adapted to circulate in said open hydraulic circuit for driving the secondary winch:
a pressure regulator for regulating the pressure of the fluid in the open hydraulic circuit;
a control unit configured for:
executing a combined operating condition, wherein the main winch and the secondary winch apply a force simultaneously to lift said actuation unit;
receiving signals related to values sensed by the first pressure sensor and the second pressure sensor, or by the second pressure sensor and the current sensor; and, based on such the values, controlling the pressure regulator so that the pressure of the fluid in the open hydraulic circuit, during the combined operating condition, takes a target value that is a function of: the pressure of the fluid in the closed hydraulic circuit or, respectively, the electric current in the electric circuit:

wherein, at predefined time intervals, the control unit is configured for:
measuring the pressure of the fluid in the open hydraulic circuit,
measuring the pressure of the fluid in the closed hydraulic circuit or, respectively, the current in the electric circuit,
regulating the pressure of the fluid in the open hydraulic circuit in order to bring the pressure to the target value:

wherein the target pressure value is calculated with one of the following formulae:

Ptarget=Pprinc×(100−R)/100+Ppd×R/100

Ptarget=Iprinc×k×(100−R)/100+Ppd×R/100
wherein R is a coefficient that is indicative of the different physical characteristics of the main and secondary winches; k is a predetermined coefficient.