US 12,215,481 B2
Construction equipment
Dongsoo Kim, Gyeongsangnam-do (KR); and Miok Kim, Gyeongsangnam-do (KR)
Assigned to VOLVO CONSTRUCTION EQUIPMENT AB, Eskilstuna (SE)
Appl. No. 17/601,141
Filed by VOLVO CONSTRUCTION EQUIPMENT AB, Eskilstuna (SE)
PCT Filed Apr. 5, 2019, PCT No. PCT/KR2019/004108
§ 371(c)(1), (2) Date Oct. 4, 2021,
PCT Pub. No. WO2020/204238, PCT Pub. Date Oct. 8, 2020.
Prior Publication US 2022/0170238 A1, Jun. 2, 2022
Int. Cl. E02F 9/20 (2006.01); E02F 9/22 (2006.01); E02F 9/26 (2006.01); G05D 3/20 (2006.01)
CPC E02F 9/2033 (2013.01) [E02F 9/2214 (2013.01); E02F 9/262 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A construction equipment comprising:
an undercarriage;
an upper swing body rotatably supported on the undercarriage;
a work device supported by the upper swing body and comprising a boom, an arm, and a bucket, which operate by means of respective hydraulic cylinders;
a control valve for controlling the boom cylinder;
an electronic proportional pressure reducing valve for controlling a spool of the control valve;
a control lever for outputting a control signal corresponding to the amount of control of a driver;
a work setting unit for providing a work mode and a target work surface setting function;
a location information providing unit for, according to a work setting of the work setting unit, collecting and/or calculating location information of the work device and location information of a work surface that has been set; and
an electronic control unit for calculating and outputting boom pilot pressure for the electronic proportional pressure reducing valve,
wherein the electronic control unit controls the operation of the boom by using the control signal of the control lever and the location information collected and/or calculated by the location information providing unit,
wherein the electronic control unit sets the location of the bucket end as a first point, the joint location of the boom and the arm as a second point, and an angle between a virtual straight line connecting the first point and the second point and the work surface as a boom control angle value,
wherein the electronic control unit calculates the boom control angle value, and compares the calculated boom control angle value with the set reference value,
wherein the electronic control unit determines the boom control angle value to be in boom-up control range and allows only boom-up movement in case the boom control angle value is smaller than the set reference value, and determines the boom control angle value to be in boom-down control range and allows only boom-down movement in case the boom control angle value is larger than the set reference value.