Abstract: On an upper revolving structure, an engine having an exhaust port is mounted. In the midway portion of the exhaust pipe connecting the exhaust port of the engine and an exhaust gas post-treatment device, a first bellows pipe and a second bellows pipe are arranged through a connecting pipe having an L-shaped bending portion. In this case, the first bellows pipe and the second bellows pipe are arranged so as to have a positional relationship in which axis lines thereof (X1-X1, Z1-Z1) cross each other. That is, the first bellows pipe is arranged in a horizontal direction so that its axis line (X1-X1) extends in the left-right direction of the upper revolving structure. The second bellows pipe is arranged so that its axis line (Z1-Z1) matches the vertical direction of the upper revolving structure.

Abstract: A hydraulic drive system for a working machine provides improved safety during forced regeneration. Upon input of a forced regeneration command signal from a forced regeneration switch, a controller detects non-operated states of all hydraulic actuators such as an arm cylinder arranged on a hydraulic excavator based on a lock detection signal from a gate lock detection switch, and also an attitude of a front working mechanism. The attitude is proper from the standpoint of safety. The detection is based on an arm angle signal from an arm angle sensor, a bucket angle signal from a bucket angle sensor and a boom pressure signal from a boom pressure sensor. Taking the detection of the non-operated states and proper attitude as conditions, the controller outputs control signals to a boosting proportional solenoid valve and flow-rate controlling, proportional solenoid valve to make a forced regenerator conduct forced regeneration.

Abstract: A prime mover revolution speed control system for a hydraulic construction machine sets the revolution speed of the prime mover in accordance with the operating state invoked by an operating command and as a result of a determination of an excavation state so that that the revolution speed of the engine can be increased for a heavy load (speedup) in the excavation state. When the control lever is fully operated in the direction of arm crowding, the control lever 43 is also operated, and first judgment conditions are all met to conclude that an excavation state has begun. During excavation work, when the control lever 44 is subjected to a half or greater operation in the arm crowding direction, second judgment conditions are all met to conclude that the excavation state persists, and the speedup sequence is continued.

Abstract: To provide a construct ion machine in which the temperature of a battery and aqueous urea within an aqueous urea tank can be prevented from rising and high stability can be secured in the vehicle body.

Abstract: An aqueous urea tank structure is provided for a construction machine, in which a temperature rise of the aqueous urea within the tank can be suppressed and the load applied to the tank due to vibration of a vehicle body can be reduced. The aqueous urea tank structure including an aqueous urea tank which is disposed within a revolving upperstructure of a hydraulic excavator to store aqueous urea that purifies the exhaust gas discharged from an engine, wherein the aqueous urea tank structure further includes a securing member which encloses the periphery of the aqueous urea tank to secure the aqueous urea tank within the revolving upperstructure, and heat insulating materials which are interposed between the securing member and the aqueous urea tank to hold the aqueous urea tank. The securing member contains a box.

Abstract: A relief pressure control system is provided with a controller for outputting, responsive to an adjustment signal output from a dial switch, a control signal to control a relief pressure of a variable solenoid relief valve, a display unit for displaying, responsive to display signals outputted from the controller, a relationship between a circuit pressure output from a pressure sensor and a pressure required by a hydraulic cylinder, and a control device constituting a start instruction unit for instructing a start of control of the variable solenoid relief valve. Stop valves are arranged in sections of main lines, which communicate a directional control valve and the hydraulic cylinder with each other, to open or close the section. The sections are located between positions on the main lines, where the variable solenoid relief valves are connected to the main lines, respectively, and the hydraulic cylinder.

Abstract: Disclosed is a hydraulic drive system for a working machine, which enables to conduct forced regeneration continuously for a sufficient time. Based on an input of a lock detection signal S1 from a gate lock detection switch 40, a controller 50 detects that a gate lock lever 32 for controlling a gate lock on/off valve 33 is in a locked state, in other words, hydraulic actuators such as an arm cylinder 12 arranged on a hydraulic excavator 1 are all in non-operated states. Upon an input of a forced regeneration command signal So from a forced regeneration switch 53 in this detected state, control signals Cp,Cf are outputted to a boosting control valve 51 and regulator 52 to make a forced regeneration means (an arm cylinder control valve 27 and the regulator 52) conduct forced regeneration.

Abstract: An exhaust gas treatment filter removes particulate matter from exhaust gas of a diesel engine. The particulate matter which accumulates on the filter is removed by a manual regeneration system that can simply be controlled. After a manual regeneration switch 22 is shifted to an ON-position, a load control section 66 keeps at least one of the revolution speed N of an engine 1, the displacement volume q and discharge pressure P of a hydraulic pressure pump 11 at a corresponding first target value (N1, q1, or P1) or second target value (N2, q2, or P2) depending on a temperature of the cooling water in relation to a flame-out prevention temperature T1. A regeneration control section 67 starts the compulsory regeneration after the manual regeneration switch has been shifted to the ON-position and when the cooling water temperature is equal to or higher than T1.

Abstract: A hydraulic driving device for a working machine surely prevents behavior of a single rod double acting cylinder not intended by an operator when discharge pressure of a main pump is raised to raise exhaust gas temperature to temperature required for burning particulate matter. A selector valve 160 interposed between a spool valve 61 and a rod chamber of a single rod double acting cylinder 51 and a section (a filter regeneration time actuation valve 122, a vehicle body controller 150) controlling the selector valve, are provided. A switch control section prevents a flow of oil directed from the rod chamber of the cylinder toward the spool valve by actuating the selector valve by a poppet of the selector valve when a by-pass cut valve 110 is controlled to increase a load of an engine 21 to a degree exhaust gas temperature reaches temperature required for burning particulate matter.

Abstract: A hydraulic drive system realizes a jack-up operation without arrangement of a flow rate control valve and center bypass selector valve. The hydraulic drive system has first and second hydraulic pumps, first and second directional control valves for controlling boom cylinders, a third directional control valve for controlling the boom cylinders, and a third hydraulic pump for feeding pressure oil to the third directional control valve. A jack-up selector valve has a second select position where, when a pressure in bottom chambers of the boom cylinders is not higher than a predetermined pressure, feeding of pressure oil, which is delivered from the first hydraulic pump and second hydraulic pump, to rod chambers of the boom cylinders, is held permissible in association with switching of the second directional control valve and third directional control valve by a manipulation of a control device.

Abstract: An exhaust gas cleaning system is provided in an engineering vehicle such as a hydraulic excavator. During automatic regeneration, when a gate lock lever 5 is in a locked state and work is not performed, the exhaust gas temperature detected by the exhaust temperature detecting device 37 may be lower than the threshold value, so temperature-rising assistance is started as follows. The minimum engine output PS1 (pump discharge pressure P1 and pump discharge amount Q1) is brought to engine output PS2 (pump discharge pressure P2 and pump discharge amount Q2). In this way, a hydraulic load is applied to an engine to thereby increase exhaust gas temperature. When the work is resumed during the regeneration, an operator pulls down the gate lock lever to the first position A, and the engine output is returned to PS1. Thus, the temperature-rising assistance is stopped, however the automatic regeneration is continued.

Abstract: Disclosed is a hydraulic drive system for a working machine, which enables to conduct forced regeneration continuously for a sufficient time. Based on an input of a lock detection signal S1 from a gate lock detection switch 40, a controller 50 detects that a gate lock lever 32 for controlling a gate lock on/off valve 33 is in a locked state, in other words, hydraulic actuators such as an arm cylinder 12 arranged on a hydraulic excavator 1 are all in non-operated states. Upon an input of a forced regeneration command signal So from a forced regeneration switch 53 in this detected state, control signals Cp,Cf are outputted to a boosting control valve 51 and regulator 52 to make a forced regeneration means (an arm cylinder control valve 27 and the regulator 52) conduct forced regeneration.

Abstract: A hydraulic drive system for a working machine provides improved safety during forced regeneration. Upon input of a forced regeneration command signal from a forced regeneration switch, a controller detects non-operated states of all hydraulic actuators such as an arm cylinder arranged on a hydraulic excavator based on a lock detection signal from a gate lock detection switch, and also an attitude of a front working mechanism. The attitude is proper from the standpoint of safety. The detection is based on an arm angle signal from an arm angle sensor, a bucket angle signal from a bucket angle sensor and a boom pressure signal from a boom pressure sensor. Taking the detection of the non-operated states and proper attitude as conditions, the controller outputs control signals to a boosting proportional solenoid valve and flow-rate controlling, proportional solenoid valve to make a forced regenerator conduct forced regeneration.

Abstract: A prime mover revolution speed control system for a hydraulic construction machine sets the revolution speed of the prime mover in accordance with the operating state invoked by an operating command and as a result of a determination of an excavation state so that that the revolution speed of the engine can be increased for a heavy load (speedup) in the excavation state. When the control lever is fully operated in the direction of arm crowding, the control lever 43 is also operated, and first judgment conditions are all met to conclude that an excavation state has begun. During excavation work, when the control lever 44 is subjected to a half or greater operation in the arm crowding direction, second judgment conditions are all met to conclude that the excavation state persists, and the speedup sequence is continued.

Abstract: A developing device includes a developer carrying member for carrying a magnetic developer to form a developer image on an image bearing member; a developing device frame including a first accommodating chamber for accommodating the magnetic developer and including a second accommodating chamber, in which the developer carrying member is provided, for accommodating the magnetic developer supplied from the first accommodating chamber through a first opening; a removable sealing member for sealing the first opening; and a magnetic seal, provided between a longitudinal end portion of the developer carrying member and the developing device frame. The sealing member is removable through a second opening which is defined at least partly by the magnetic seal.

Abstract: A hydraulic drive device for a construction machine which can reliably judge whether or not the state of the construction machine is appropriate for stopping an engine is provided. The hydraulic drive device includes: a main pump 13; a regulator 15 that controls the discharge rate of the main pump 13 by a control pressure Pc; an engine 16 that drives the main pump 13; an engine stopping unit 83 that stops the engine 16 when a predetermined state of the construction machine has continued for a predetermined period of time; and a pressure sensor 72 that detects the control pressure Pc. The engine stopping unit 83 has a control signal judging unit 81 that judges whether or not the control pressure Pc detected by the pressure sensor 72 is lower than a predetermined pressure value Pc1, as a judgment of whether or not the predetermined state of the construction machine is present.

Abstract: A process cartridge that is provided with an image bearing member and a development device and is detachably attached to an apparatus body includes a developer carrying member that carries a developer, a magnetic member housed inside, an interval defining member that defines an interval between the surface of the developer carrying member and the surface of the image bearing member, and a support member that can support the magnetic member at a first position, at which a developing operation is performed, and a second position, at which a nearest distance between the surface of the developer carrying member and the surface of the magnetic member is greater than that at the first position.

Abstract: An exhaust gas treatment filter removes particulate matter from exhaust gas of a diesel engine. The particulate matter which accumulates on the filter is removed by a manual regeneration system that can simply be controlled. After a manual regeneration switch 22 is shifted to an ON-position, load control section 66 keeps at least one of the revolution speed N of an engine 1, the displacement volume q and discharge pressure P of a hydraulic pressure pump 11 at a corresponding first target value (N1, q1, or P1) or second target value (N2, q2, or P2) depending on a temperature of the cooling water in relation to a flame-out prevention temperature T1. A regeneration control section 67 starts the compulsory regeneration after the manual regeneration switch has been shifted to the ON-position and when the cooling water temperature is equal to or higher than T0.

Abstract: To provide a heat exchanger assembly for a construction machine, which can facilitate attachment/detachment work of dustproof nets and can attach the dustproof nets with suppressed flapping. A heat exchanger assembly for a construction machine is provided with heat exchangers mounted on a frame for cooling a drive source mounted on the frame, a fan mounted on the frame for supplying cooling air to the heat exchangers, and dustproof nets arranged upstream of the heat exchangers in a flow of the cooling air produced by the fan. The dustproof nets are each provided with a net section held taut within a frame section, and a clipping part attached to the frame section. The clipping part is arranged such that it can be releasably fastened to a clipped part arranged on the corresponding heat exchanger. The clipping part is provided at its end portion with a bent portion. At least one of the bent portion 34e and the clipped part is provided with an elastic member.

Abstract: A hydro-static transmission travel system for a working machine enables the working machine to travel over a range from low speed to high speed with a simplified circuit arrangement. By referring to a machine traveling speed (vehicle speed) based on a detected signal from a rotation sensor, a controller computes respective target tilting amounts of hydraulic motors 10, 20 and controls the tilting amount for the hydraulic motors and a clutch. Depending on whether the traveling speed exceeds a setting speed as a reference boundary, the controller selectively switches over a drive mode between low-speed four-wheel drive, in which travel units 12, 22 are both driven, and high-speed two-wheel drive, in which the front-wheel side hydraulic motor 10 is controlled to zero displacement and only the rear-wheel side travel unit 22 is driven.