Abstract: A monitoring region for monitoring entry of an obstacle is set around a machine main body. A plurality of obstacle sensing sensors sense an obstacle in the monitoring region and sense an obstacle in different directions with respect to the machine main body. A construction machine accumulatively stores approach information indicating that an obstacle has been sensed by any of the plurality of obstacle sensing sensors in a specific period, and outputs the approach information to be displayed on a display device.

Abstract: A monitoring region for monitoring entry of an obstacle is set around a machine main body. A plurality of obstacle sensing sensors sense an obstacle in the monitoring region and sense an obstacle in different directions with respect to the machine main body. A construction machine accumulatively stores approach information indicating that an obstacle has been sensed by any of the plurality of obstacle sensing sensors in a specific period, and outputs the approach information to be displayed on a display device.

Abstract: A demountable pillar 16 is demountably mounted to an upper frame bottom plate 9 and a floor plate 10. A spacer 35 is detachably attached to the demountable pillar 16. The spacer 35 is detached in a state that an upper load is supported by a lifting bolt 39 to reduce the height of the demountable pillar 16, and the demountable pillar 16 is demounted in a state that the upper load is supported by the other pillars. A fuel tank 11 as a device is removed from between the upper frame bottom plate 9 and the floor plate 10 in this state.

Abstract: A demountable pillar 16 is demountably mounted to an upper frame bottom plate 9 and a floor plate 10. A spacer 35 is detachably attached to the demountable pillar 16. The spacer 35 is detached in a state that an upper load is supported by a lifting bolt 39 to reduce the height of the demountable pillar 16, and the demountable pillar 16 is demounted in a state that the upper load is supported by the other pillars. A fuel tank 11 as a device is removed from between the upper frame bottom plate 9 and the floor plate 10 in this state.

Abstract: In a structure where a floor plate (10) is mounted above a bottom plate (9) of an upper frame while being supported by a plurality of pillars, a left-rear pillar (16) required to be demounted and re-mounted, among the plurality of pillars, is provided with a spacer (35) adapted to increase a height dimension of the pillar (16), and a combination of a screw hole and a bolt (39) which serve as screw unit adapted to support a load to be applied to the spacer (35), in place of the spacer (35). Under a condition that the load is supported by the screw unit, the spacer (35) is detached to reduce the height dimension of the pillar (16). Then, under a condition that the load is supported by the remaining pillars, the left-rear pillar (16) is demounted.