Abstract: A current control apparatus capable of accurately and stably controlling a current which is supplied to an object of control such as a coil of a solenoid even when a control target value varies greatly at a predetermined time interval. In this apparatus, a value (y3) of a current passing through the object of control (33) is detected, and the detected current value (y3) is output at a predetermined time intervals. On the basis of a preceding corrected current value (y4old) and a presently outputted current value (y3), a presently corrected current value (y4) is computed so that this value comes to be intermediate between the preceding corrected current value (y4old) and presently outputted current value (y3), and the resultant current value is output.

Abstract: To prevent a display screen from being reflected on glass shields, without lowering the visibility of a display portion.

Abstract: Even if state indication marks and state change indication marks are increased in numbers, the indication marks of the two types can be displayed on a common display screen of a limited area without reducing the sizes of the individual marks thereby to invite neither a larger size of a display device nor a drop in the visibility of the indication marks and to cause no trouble in the driving control of a working machine such as a construction machine.