US 11,668,069 B2
Construction machine
Shinji Ishihara, Tokyo (JP); Hiroshi Sakamoto, Tsuchiura (JP); Hidekazu Moriki, Tokyo (JP); and Ryu Narikawa, Tokyo (JP)
Assigned to HITACHI CONSTRUCTION MACHINERY CO., LTD., Tokyo (JP)
Appl. No. 16/760,530
Filed by HITACHI CONSTRUCTION MACHINERY CO., LTD., Tokyo (JP)
PCT Filed Nov. 8, 2018, PCT No. PCT/JP2018/041499
§ 371(c)(1), (2) Date Apr. 30, 2020,
PCT Pub. No. WO2019/093424, PCT Pub. Date May 16, 2019.
Claims priority of application No. JP2017-218071 (JP), filed on Nov. 13, 2017.
Prior Publication US 2021/0040705 A1, Feb. 11, 2021
Int. Cl. E02F 3/43 (2006.01); E02D 3/046 (2006.01); E02F 9/22 (2006.01)
CPC E02F 3/435 (2013.01) [E02D 3/046 (2013.01); E02F 9/2203 (2013.01)] 4 Claims
OG exemplary drawing
 
1. A construction machine comprising:
a machine body;
an articulated front work implement disposed anterior to the machine body and including a boom, an arm, and a bucket;
a plurality of hydraulic actuators including a boom cylinder that drives the boom, an arm cylinder that drives the arm, and a bucket cylinder that drives the bucket;
an operation device that is operated by an operator to instruct an operation of each of the boom, the arm, and the bucket;
a boom posture sensor that senses a posture of the boom;
an arm posture sensor that senses a posture of the arm;
a bucket posture sensor that senses a posture of the bucket; and
a controller that controls drive of the hydraulic actuators in response to an operation of the operation device,
the controller configured to perform:
setting a leveling target surface,
determining a target velocity of the bucket such that the bucket does not advance further down the leveling target surface, and,
during leveling work, notifying the operator of details of an operation of the operation device for achieving the target velocity of the bucket or controlling drive of the hydraulic actuators so as to achieve the target velocity of the bucket, wherein
the controller is configured to
determine whether or not compaction work is in progress,
calculate a front distance that represents a distance between a rotational pivot of the boom and a predetermined position in a back surface of the bucket,
determine the target velocity of the bucket such that a velocity with which the bucket approaches the leveling target surface decreases with increasing values of the front distance, and,
during the compaction work, notify the operator of details of an operation of the operation device, the details being used for achieving the target velocity of the bucket, or control drive of the hydraulic actuators so as to achieve the target velocity of the bucket.