Abstract: A cooling air introduction path is formed in a base of a sound proof case of an engine-driven work machine. The base is divided into upper and lower portions, and a space in the upper portion is divided by a separation wall and arranged below an air discharging chamber. The upper part of one space is covered with a arranging plate, a partition wall is erected on the arranging plate, and a cooling air introduction port is provided between the partition wall and the separation wall to provide an engine chamber and one space are communicated, a hole is provided in the plate below the chamber, and one space and the space in the lower portion are communicated and located below the chamber. A cooling air intake port is provided on lateral walls of the lower portion to communicate the space inside the lower portion with the outside of the machine.

Abstract: In a method for operation control of a compressor, full-load running in which a gas intake control valve is fully open and a target rotation speed of a drive source is set to a full-load rotation speed that is a maximum rotation speed in a speed control band when pressure of compressed gas supplied to the consumption side is a datum pressure or less is carried out; then no-load running in which the valve is fully closed and a no-load rotation speed is set as the target rotation speed of the drive source when the supply pressure is a no-load running pressure or less that is a pressure higher than the datum pressure is carried out. The no-load running is started from the standard no-load rotation speed, however, after a transition time, the target rotation speed is reduced to a low speed no-load rotation speed.

Abstract: Reduction of minimum turning radius of an aerial work platform. Drive motors are provided to driven wheels of the platform respectively, so that the driven wheels can be independently controlled in terms of rotational speed and rotation direction. When the steering angle of steered wheels is at most a first steering angle, constant velocity control is performed, driving both of the driven wheels in the same rotation direction and at the same rotational speed. When the steering angle exceeds the first steering angle and is at most a second steering angle, differential control is performed, reducing the rotational speed of the driven wheel on the inside in the turning direction relative to the driven wheel on the outside in the turning direction. When the steering angle exceeds the second steering angle, counter-rotation control is performed, counter-rotating the driven wheel that is on the inside in the turning direction.

Abstract: Provided is a forced-regeneration treatment method for an exhaust-gas aftertreatment device (DPF) and an associated engine-driven compressor. When the amount of particulate matter (PM) deposited in a filter element of a DPF reaches a predetermined amount and a forced-regeneration start command is input, a capacity controlling means of the engine-driven compressor is disabled to close an intake valve and to open the discharge side of a compressor main unit to atmosphere, thereby causing the compressor main unit to achieve a low-load state. The operation mode of the engine is switched to a predetermined forced-regeneration mode to operate the engine at a predetermined speed and to increase the temperature of the gas. The temperature inside the DPF is increased to reach a temperature at which an oxidative catalyst is activated and to a temperature lower than the self-combustion temperature of the PM, thereby forcibly burning the PM.

Abstract: Provided is a forced-regeneration treatment method for an exhaust-gas aftertreatment device (DPF) and an associated engine-driven compressor. When the amount of particulate matter (PM) deposited in a filter element of a DPF reaches a predetermined amount and a forced-regeneration start command is input, a capacity controlling means of the engine-driven compressor is disabled to close an intake valve and to open the discharge side of a compressor main unit to atmosphere, thereby causing the compressor main unit to achieve a low-load state. The operation mode of the engine is switched to a predetermined forced-regeneration mode to operate the engine at a predetermined speed and to increase the temperature of the gas. The temperature inside the DPF is increased to reach a temperature at which an oxidative catalyst is activated and to a temperature lower than the self-combustion temperature of the PM, thereby forcibly burning the PM.

Abstract: In a continuous regeneration type exhaust gas post-processing apparatus equipped with an oxidation catalyst (DOC) and a diesel particulate filter (DPF), reliably removing particulate matter (PM) deposited to the DOC for maintaining the activity performance of DOC. The present invention relates to a method of forcibly regenerating a continuous regeneration type exhaust gas post-processing apparatus installed in an engine-driven generator equipped with a generator body driven by a diesel engine. When the engine is in a predetermined light load running state during forced regeneration in which intake gas to the engine is restricted to increase a temperature of exhaust gas, a heater actuated with electricity generated by the generator body switches ON in order to increase a load on the engine and thus a DOC inlet temperature of the exhaust gas post-processing apparatus to a burning temperature of PM deposited in the DOC or more.

Abstract: A rotor 1 forming screw teeth is projectingly provided at its outer end 2 on the axis thereof with a center shaft 3. The center shaft 3 is provided at its outer end 4 with a smaller-diameter shaft 5 or a concaved fitting hole. A separate rotor shaft 6 which is to be fitted over the smaller-diameter shaft 5 or fitted into the concaved fitting hole is provided with another concaved fitting hole 7 or smaller-diameter shaft. A metal shaft around which synthetic resin is molded is formed at its peripheral surface with a spiral groove or corrugated groove in the opposite revolutional direction with respect to the revolutional direction of the screw rotor. The spiral groove is formed with smooth arc curved line connecting profiles of adjacent grooves. The shaft is provided with a step, and synthetic resin is molded around the shaft surface to form a screw rotor.

Abstract: A revolving construction machine includes a lower track structure, an upper revolving structure mounted on the lower track structure and a working device mounted to the front of the upper revolving structure. A floor panel portion is provided on the upper revolving structure. A walk-through passageway is defined by a left-hand floor panel portion, a left side portion of a cabin cover and a left-hand cover of an engine cover for allowing a person to walk through the construction machine in the front and rear directions by passing the left side of an operator's seat, the cabin cover and the engine cover.

Abstract: A rotor 1 forming screw teeth is projectingly provided at its outer end 2 on the axis thereof with a center shaft 3. The center shaft 3 is provided at its outer end 4 with a smaller-diameter shaft 5 or a concaved fitting hole. A separate rotor shaft 6 which is to be fitted over the smaller-diameter shaft 5 or fitted into the concaved fitting hole is provided with another concaved fitting hole 7 or smaller-diameter shaft. A metal shaft around which synthetic resin is molded is formed at its peripheral surface with a spiral groove or corrugated groove in the opposite revolutional direction with respect to the revolutional direction of the screw rotor. The spiral groove is formed with smooth arc curved line connecting profiles of adjacent grooves. The shaft is provided with a step, and synthetic resin is molded around the shaft surface to form a screw rotor.

Abstract: Rotary machine such as rotary compressor or expander having meshed male and female rotor assembly. The tooth profile of the female rotor is formed such that a line (H.sub.2 -A.sub.2) is formed by a generated curve of a point A.sub.1 of the male rotor; a line (A.sub.2 -B.sub.2) is formed by a circular arc having a point O.sub.7 as the center of the arc and a radius R.sub.7 ; a curve (B.sub.2 -C.sub.2) is formed by an envelope developed by a circular arc (B.sub.1 -C.sub.1) of the male rotor; a portion between points D.sub.2 and E.sub.2 is formed by a circular arc having a point O.sub.1 as the center of the arc and a radius R.sub.1 ; a line (C.sub.2 -D.sub.2) is formed by a line smoothly connecting the curves (B.sub.2 -C.sub.2) and (D.sub.2 -E.sub.2); a curve (E.sub.2 -F.sub.2) is formed by a circular arc having a point O.sub.2 as the center of the arc and a radius R.sub.2 ; and a curve (F.sub.2 -G.sub.2) is formed by a circular arc having a point O.sub.8 as the center of the arc and a radius R.sub.8.

Abstract: A screw rotor assembly having nonsymmetrical tooth profiles and used in a screw-type rotary compressor or expander. The tooth profile of the female rotor is formed such that a line (H.sub.2 -A.sub.2) is formed by a generated curve of a point A.sub.1 of the male rotor; a line (A.sub.2 -B.sub.2) is formed by a circular arc having a point O.sub.7 as the center of the arc and a radius R.sub.7 ; a curve (B.sub.2 -C'.sub.2) is formed by an envelope developed by a circular arc (B.sub.1 -C.sub.1) of the male rotor; a portion between points D'.sub.2 and E.sub.2 is formed by a circular arc having a point O.sub.1 as the center of the arc and a radius R.sub.1 ; a line (C'-D') is formed by a line smoothly connecting the curves (B.sub.2 -C'.sub.2) and (D'.sub.2 -E.sub.2); a curve (E.sub.2 -F.sub.2) is formed by a circular arc having a point O.sub.2 as the center of the arc and a radius R.sub.2 ; and a curve (F.sub.2 -G.sub.2) is formed by a circular arc having a point O.sub.8 as the center of the arc and a radius R.sub.8.

Abstract: A control circuit for a self-excited AC generator including an automatic voltage regulator, a fly-wheel capacitor which is charged normally by part of the generator output during a no-load operation or small-load operation of the generator, a detection circuit which detects a drop of the generator output voltage when said output voltage drops below the predetermined value, and a field current control circuit which operates on the fly-wheel capacitor to discharge the stored electric energy to the field winding of the generator or an exciter equipped with the generator when the detection circuit detects a drop of the generator output voltage. The control circuit provides additionally with the second field current control circuit which supplies a current from the generator output terminal to the field winding through a rectifier when the detection circuit detects a drop of the generator output voltage.