Hitachi Construction Machinery Co., Ltd.

Hitachi Construction Machinery Tierra Co., Ltd.

Hajime Ishii

Hiroshi Tabeta

Shogo Kimura

Tomoyuki Tanaka

Hajime Yoshida

Shigeru Hirasawa

Shougo Kimura

Shuuhei Noguchi

Yoshifumi Takebayashi

Masayuki Yunoue

Hajime Kurikuma

Teruo Irino

Syuuhei Noguchi

Shogo Room 1505 Jiokouto Ritto Kimura

Hiroshi Room 201 Wind View A Tabeta

Masayuki Room 402 Erufouto 31 Yunoue

Shigeru Room 102 Heights Newtown Hirasawa

An engine () electronically controlled by a control device (), a hydraulic motor () for traveling which is driven by a pressurized oil delivered from a hydraulic pump (), and a traveling speed switching member () which switches a traveling speed by the hydraulic motor () at least in two stages of a low speed and a high speed. The control device () includes an output lowering determination unit for determining whether or not a fuel injection amount to be supplied to the engine () is limited and an engine output is in a lowered state and a low-speed control unit in which, when the engine () output is in a lowered state, a traveling speed is controlled to a low speed state kept lower than a high speed even if the traveling speed switching member () has been switched to the high speed side.

Construction machine

A control pressure switching valve is disposed between a displacement regulator and a pressure control valve. The control pressure switching valve is switched between a control position (j), in which a load sensing control pressure (PLS) is permitted to be outputted from the pressure control valve to the displacement regulator, and a control release position (k), in which the load sensing control pressure (PLS) to be outputted to the displacement regulator is reduced to a prescribed low pressure value. When the regeneration of a filter is determined to be necessary, the controller switches the control pressure switching valve to the control release position (k). When the load sensing control pressure (PLS) is reduced to the low pressure value with the control pressure switching valve switched to the control release position (k), the displacement regulator increases a delivery displacement of a hydraulic pump, thereby increasing rotational load of an engine.

[Problem] To provide a construction machine with a step arranged in an operator's cab, which makes it possible to enlarge the shape or dimensions of the step without increasing a swing radius. [Solution] In a compact excavator provided with a step that facilitates ingress to and egress from the operator's cab (), the step is provided at a part thereof with an outwardly-extending edge portion () that extends out beyond an opening plane () forming an ingress/egress opening (), and a door () is provided at a part thereof with a convex part () that covers the outwardly-extending edge portion () of the step when the door () is in a closed position. A floor () of the operator's cab () includes a flat part () arranged on a front side of a seat () and a stepped part () arranged in conjunction with the flat part () and on a side of the ingress/egress opening, a flange part () which lies in a same plane as the stepped part () of the floor () is arranged in conjunction with the stepped part () and in the operator's cab (), the step includes the stepped part () of the floor () and the flange part (), and the flange part () is provided with the outwardly-extending edge portion ().

Construction machinery

An upper revolving structure () includes a revolving frame (), a floor member () which is provided on the revolving frame () and a front side of which serves as a footrest section () on which an operator rests his or her feet, a cab box () which forms an operating room () above the floor member (), and an indoor unit () disposed on the floor member () to supply sucked air as conditioned air. A lower surface (B) side of the footrest section () of the floor member () is formed as a unit mounting surface (), and, as for the indoor unit (), a box body () is disposed on the lower side of the unit mounting surface () and, in this state, the box body () is mounted on the unit mounting surface () by means of a plurality of bolts ().

A compact excavator includes an operator's cab with a door capable of opening and closing an opening surface forming a boarding port. The door includes one door piece, and has a flexing portion which is closer to a front pillar than the central portion of the door when the door is in a closed state. The flexing portion is shaped to have a first area so formed that when the door is in a closed state, the first area approaches the opening surface as the first area approaches the front pillar, and a second area arranged continuously with the first area and nearer the front pillar than the first area and being formed so that the second area draws away from the opening surface as the second area approaches the front pillar.

A regeneration apparatus for executing a regeneration process to an exhaust gas purifying apparatus and an engine control device that controls a rotational speed of an engine according to an instruction value by a rotational speed instruction apparatus are provided. When a directional control valve is in a neutral position, the engine control device controls the rotational speed of the engine to an automatic idle rotational speed (Nai) by an automatic idle selection unit regardless of the instruction value. However, when it is determined that the regeneration process of the exhaust gas purifying apparatus is executed in a state of controlling the rotational speed of the engine at the automatic idle rotational speed (Nai), the engine control device increases the rotational speed of the engine to a regeneration processing rotational speed (N1) higher than the automatic idle rotational speed (Nai).

Provided is a hybrid construction machine capable of facilitating the hybridization (conversion, redesigning, etc. into a hybrid construction machine) even for construction machines of the minimal tail swing radius type or the minimal swing radius type. A hybrid mini-shovel of the minimal tail swing radius type comprises an engine, a hydraulic pump whose input shaft is coaxially connected to the output shaft of the engine, a generator/motor whose rotating shaft is connected to the output shaft of the engine and the input shaft of the hydraulic pump via a gear mechanism, and a battery which receives and supplies electric power from/to the generator/motor. The generator/motor is placed at a vertical position where its lower end is situated above the shaft center of the input shaft of the hydraulic pump, and when viewed from above at a horizontal position where it overlaps with the hydraulic pump.

Hybrid construction machine

A floor member is formed by a seat support platform on a rear side and a footrest area located on a front side of the seat support platform, and a cab box is formed by a front panel, a rear panel, a left front side panel, a left rear side panel, a right side panel, and a top panel. A right reinforcing panel is provided at a right side position of the floor member and rises upwardly of the footrest area. The right side panel of the cab box corresponding to this right reinforcing panel is provided with a notched portion for avoiding interference with the right reinforcing panel. Accordingly, since the strength at the right side position of the floor member can be enhanced by the right reinforcing panel, it is possible to prevent deformation such as torsion and distortion when the floor member is tilted up.

A suction duct () provided in a floor member () comprises an internal air duct portion () connected to the internal air inlet port (A), an external air duct portion () connected to an external air inlet port (E), and a common duct portion () for connecting the internal air duct portion () and the external air duct portion () to a blower fanB suction side of an air conditioner unit (). The suction duct is constructed to form a hollow column () having a hollow closed section structure with the internal air duct portion and the common duct portion formed integrally in the upper and lower directions. Therefore, the hollow column formed of the hollow closed section structure can increase strength of the floor member as a strong column while circulating internal air between the internal air inlet port and the air conditioner unit.

A seat support platform () is provided on a floor panel () of a floor member () of a cab (). An air conditioner unit () is installed internally of the seat support platform (). An under floor duct () is provided on the lower side surface (C) of the floor panel () to form an external air induction passage () to guide external air from outside of the cab () toward an external air intake port (H) of the air conditioner unit (). Under floor duct () can be provided integrally with the floor member () without protrusion to the lower side, and the under floor duct () can supply cool external air into the cab (). Even in the case of a small size hydraulic excavator, the under floor duct () can be provided integrally on the floor member () to secure broader space in the cab ().

A folding type door is fitted in a cab box. Two door panels and are disposed substantially in the same vertical plane as a left side cover of an upper revolving structure when said door in a closed position. Catches and are provided in a left rear side section of the cab box. Provided on door panels and of the folding type door are strikers and to be attachably or detachably engaged with the catches and separately of each other. When the folding type door is opened, the respective door panels and are each retained in an open door position by engagement of two sets of strikers and catches and which prevents rattling movements of each door panel to retain the folding type door in a stabilized state.

A lower floor panel () and an upper floor panel () which is having a sunken storage portion (D) is provided in front of a seat supporting base () which supports an operator's seat () with in a cab (). A storage space () is provided between a sunken storage portion (D) in the lower floor panel () and a flat horizontal surface (A) of the upper floor panel (). This storage space () can be used for installation of an air-conditioning unit (). This lo means that the air-conditioning unit () can be accommodated in a floor portion in front of the operator's seat (), permitting to suppress the height of the cab () to an appropriate level. In addition, installation of the air-conditioning unit () can make assembling and maintenance work far easier.

A washer tank is integrally formed with a front air duct, and the washer tank and the front air duct are installed within a cab. Thus, the washer tank can be installed within the cab by the use of spaces around the air duct. This arrangement makes it possible to install the washer tank within the cab in an unintrusive way and in the vicinity of a washer liquid spout nozzle without necessitating to provide an installation space exclusively for the washer tank.

A pattern selector valve () is lodged in a seat supporting stool () which supports an operator's seat () thereon, with a switch lever (B) at a front side of the seat supporting stool. An operator can easily check out the position of the switch lever (B) of the pattern selector valve () at the time of getting onto the operator's seat (). Besides, the switch lever (B) of the pattern selector valve () can be easily changed over to a different pattern position in the vicinity of the operator's seat (). Check-out and change-over of the switch lever (B) are facilitated and can be carried out in a secure manner under guidance of a pattern indicator () which is provided on a front cover ().

A front side of a floor panel () is pivotally supported on a floor panel support mechanism (), permitting tilting of the floor panel in a forward direction with respect to a revolving frame () by way of a tilting mechanism (). The tilting mechanism () has a guide rail assembly () which is pivotally supported on the side of the revolving frame (), a screw rod () which is rotatably supported on the guide rail assembly (), and a displacement member () which is attached to the floor panel () and held in threaded engagement with the screw rod (). The floor panel () and a cab () are tilted up in the forward direction upon rotationally driving the screw rod () to translate the displacement member () constituting the tilting mechanism ().

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Higashiomi, Japan

Hajime Ishii