Abstract: [Problem] To provide a construction machine capable of realizing with fewer components temperature control of a reducing agent in a reducing agent tank without arranging any heat exchanger in the reducing agent tank.

Abstract: An exhaust gas cleaning system for an engineering vehicle, such as a hydraulic excavator, is capable of performing manual regeneration control of a regeneration fuel injector 40 that is started only under the following conditions: a manual regeneration starting switch 39 is enabled; an engine control dial 2 commands a low-speed idle revolution speed; and a gate lock lever 22 is switched to a second position B at which generation of control pilot pressures a through f by use of remote control valves 25, 26, and 27 is disabled. Even when the manual regeneration control is being executed, if the gate lock lever 22 is switched to a first position A, the manual regeneration control immediately ends. As a result, the manual regeneration control of a filter for collecting particulate matter included in the exhaust gas and the operation of the work system do not influence each other.

Abstract: [PROBLEM] To provide a construction machine capable of performing necessary operation or operations without a difficulty even when a remaining amount of a reducing agent becomes small.

Abstract: An exhaust gas purification system for an engineering machine is capable of avoiding decreases in working efficiency during regeneration control by burning off a deposit of particulate matter from a filter efficiently during a work pause time. An operating section 17 of a display monitor 16 is used to set a work pause time and a work pause switch 13 notifies a vehicle body control unit 21 that the hydraulic excavator has entered a work pause state. In response, the vehicle body control unit 21 calculates the time required for a regenerating device to burn off the current amount of particulate matter deposited on the filter, and when the calculated time is longer than the preset work pause time, a regeneration controller 4a of an engine control unit 4 is activated, and a solenoid control valve 15 is switched to a closed position during the preset work pause time.

Abstract: Before a large amount of PM is deposited in a filter, an exhaust gas cleaning system for a construction machine regenerates the filter. In a non-operational state with the engine 1 of the construction machine left running for a certain time, a controller 4 monitors the non-operational state. After this state continues for a predetermined time Ta, when the pressure sensed by a differential pressure sensor 36 is higher than a second predetermined pressure level P2, the controller 4 controls the rotating speed of the engine 1 to a predetermined speed Na before starting forced regeneration to burn off the PM deposited in a filter 32. When the pressure sensed by the differential pressure sensor 36 decreases below a first predetermined pressure level P1, the controller 4 terminates the regeneration automatically and returns the engine to normal control mode.

Abstract: Before a large amount of PM is deposited in a filter 32, an exhaust gas cleaning system for a construction machine regenerates the filter to avoid a decrease in output due to the exhaust gas pressure rise occurring immediately before the filter is regenerated, and to reduce the likelihood of unusual increases in the internal temperature of the filter due to the combustion of the PM, associated with the execution of the regeneration, and consequential thermal damage to the filter. If a value of a differential pressure across the filter 32 is greater than a predetermined pressure, a controller 4 conducts engine speed control to a predetermined rotating speed Na suitable for the regeneration, then enters forced regeneration automatically, and burns off the PM. When the sensed differential pressure decreases below a predetermined pressure, the regeneration is terminated automatically and the engine 1 is stopped.

Abstract: Each time a starting process for a diesel engine 2 is conducted and before the diesel engine 2 is started, any differences of the pressures P1 and P2 detected by first and second pressure sensors 21 and 22, respectively, with respect to a predetermined reference pressure value Pref, are computed and stored as first and second correction values ?P1 and ?P2, and then a differential pressure P12 across a particulate filter in the diesel engine 2 is computed using the pressure detection results of the first and second pressure sensors 21, 22 and the first and second correction values ?P1, ?P2. Thus, use of simply constructed and highly durable sensors during the detection of the differential pressure existing across the filter allows accurate measurement of this differential pressure.

Abstract: A ureal water tank (28), a storage of an aqueous urea solution, is located within a utility room (6G) in a right front section of a revolving frame (6), which is readily accessible from outside. In this instance, among a plurality of operating oil conduits (18), a working mechanism operating conduit (21) which supplies operating oil to a boom cylinder (5D) of a working mechanism (5) is arranged to run along exterior surfaces of the ureal water tank (28). Therefore, even if the ureal water tank (28) is located in a place with no heat source, the aqueous urea solution in the ureal water tank (28) can be stably kept in a heated state by utilization of heat of operating oil in circulation through the working mechanism operating conduit (21).

Abstract: An electric sleep inducer comprises a control circuit arranged to produce a therapeutic wave-form output which is applied at frequencies controlled non-stepwise to gradually decrease from 14 Hz to 0 Hz and adapted to a sleep indicating electroencephalogram. The circuit includes cathode and anode conductor elements for applying the therapeutic wave-form output of the control circuit to the head of a subject.