Komatsu Corporation

Komatsu Electronic Metals Co., Ltd.

Naritoshi Ohtsukasa

Hiroshi Yoshinada

Kenji Okamura

Masami Naruse

Kunikazu Yanagi

Kazuhiro Mimura

Masakazu Kobayashi

Junsuke Tomioka

Hiroshi Monden

Shoei Kurosaka

Hiroyuki Inoue

Junsei Tanaka

Toshimasa Kanda

Seiya Haga

Norihiro Aoshiba

Yuji Fukuda

Michio Chamura

By accurately determining timing for suppressing overrun in a hydraulic motor or the like, work efficiency is prevented from falling. A. pressure difference &#x394;P between pressure Pa on a discharge port side of a hydraulic pump and pressure Pb on suction port side of the hydraulic pump is calculated on the basis of the detected travel direction of the vehicle and the pressure Pa relative to Pb detected at the respective port sides of the hydraulic pump. At least one of an engine and the hydraulic pump is controlled, according to the calculated pressure difference, such that overrun of at least one of the engine, the hydraulic pump, and a hydraulic motor is suppressed.

Controller of vehicle with hydrostatic continuously variable transmission

The present invention provides a hydraulic drive apparatus which can flexibly be set. The hydraulic drive apparatus which drives a variable displacement hydraulic motorby a pressure oil discharged from a variable displacement hydraulic pumpand outputs a driving force of the hydraulic motorto outside. The hydraulic drive apparatus includes torque upper limit setting unit which sets an upper limit of an output torque with respect to the hydraulic motor, and control unit which sets a maximum capacity limit value of the hydraulic motorin accordance with the upper limit of the output torque when the upper limit of the output torque is set by the torque upper limit setting unit, and which sets a maximum capacity limit value of the hydraulic pumpin accordance with the upper limit of the output torque.

Hydraulic drive apparatus

The object of the present invention is to allow an operator to easily perform desired operations with high hydraulic efficiency, without an increase in difficulty of performing operations. A hydraulic drive apparatus of the present invention includes a pump control unitthat includes: a pump reference command value setting unitthat sets a pump reference command value for a hydraulic pumpin accordance with the engine speed of an engine; a pump correction command value calculating unitthat sets a pump command value by determining an inching rate in accordance with the amount of operation when an inching operation is performed, and correcting the pump reference command value in accordance with the inching rate; and a pump control command value setting unitthat sets a pump control command value for controlling the capacity of the hydraulic pump, based on the pump command value set by the pump correction command value calculating unit

Hydraulic drive apparatus and hydraulically-driven vehicle

Construction machinery which is capable of improving fuel efficiency of the engine and also capable of effectively utilizing surplus energy in a light-load mode. The construction machinery includes an engine, a hydraulic pump driven by the engine, and actuators driven by oil pressure supplied from the hydraulic pump. In the light-load mode where the engine torque at the intersection point of an iso-horsepower curve of the necessary horsepower and a governor characteristic curve of the engine is smaller than that of a rated output point of the engine, the number of revolutions of the engine is reduced while the engine torque is increased with respect to the intersection point, and the horsepower is made to exceed the iso-horsepower curve. With surplus torque generated therefrom, a power generator is operated so as to generate electric power, which is stored in a power accumulation apparatus.

Construction machinery

A device arrangement structure for hybrid construction equipment capable of reducing devices of a charging system in size is provided. For this purpose, in the device arrangement structure: a hydraulic pump () is connected to an engine () via a first power take-off (); and a regenerative motor (), which is regenerated by return oil from hydraulic actuators (), and a generator motor (), which assists an engine as an electric motor to drive hydraulic pump and generates power with surplus torque of the regenerative motor, are provided in parallel with the hydraulic pump via the first power take-off.

Device arrangement structure for hybrid construction equipment

Hybrid powered construction equipment is capable of making effective use of the output energy of an engine; increasing operating speed while keeping noise level low, and assuring operation power more than the performance of the engine. To this end, the hybrid powered construction equipment has a hydraulic pump powered by the engine; hydraulic actuators activated by discharge oil from the hydraulic pump; a motor-generator working in conjunction with the engine; and a battery for storing electric power generated by the electric motor-generator, the construction equipment further comprising a power-up switch disposed in an operating lever or operation panel and a controller which inputs a signal released from the power-up switch, wherein the controller constantly controls the revolution speed of the engine in response to a signal from the power-up switch and controls the output torque of the electric motor-generator such that torque for assisting powering of the hydraulic pump is output.

Hybrid powered construction equipment

Compact, low-cost construction equipment capable of effectively recovering energy from a plurality of hydraulic actuators is provided. To this end, the construction equipment comprises: a hydraulic recovery circuit for recovering return oil from the hydraulic actuators, the circuit being equipped with a pump motor rotatably driven by the recovered return oil; oil guide passages each of which is for guiding return oil from the meter-out side of its corresponding hydraulic actuator to the hydraulic recovery circuit; switches for switching the respective oil guide passages between their opened and closed states; pressure sensors for detecting the back pressure of each hydraulic pressure actuator; and a dynamo-electric generator for generating electric power from the rotary force of the pump motor.

Construction equipment

There is described an apparatus for producing a single crystal ingot capable of stably manufacturing a single crystal ingot by means of the Czochralski method, without being affected by influence of variation in extension of wires or an offset in points clamped by a clamping member. The clamping member is engaged with an engagement step formed in a single crystal which is being pulled by the CZ method, and the single crystal is pulled. The single crystal ingot manufacturing apparatus is provided with a flexible mechanism for absorbing variation in extension of the wires, in intermediate portions of the wires. Variation in extension of the wires is eliminated by means of the flexible mechanism, thereby retaining the single crystal in an upright position. Further, a sacrifice member which deforms so as to conform to the circumference of the engagement step is interposed between the clamping member and the engagement step, thereby preventing occurrence of cracking or deformation in the single crystal.

Apparatus for producing single crystal

A work machine for achieving efficient coordinated operations by a plurality of kinds of operating units, comprising first and second swivel driving members and first and second swivel joints, wherein a first swiveling base bearing a first operating unit and a second swiveling base bearing a second operating unit can swivel around a common swiveling axis independently relative to a traveling base.

Work machine

A single crystal pulling apparatus and droppage preventing device constituted so as to enable the mechanical strength required by an arm to be decreased, and to enable arm manufacturing costs to be reduced and the pulling apparatus to be made more compact, and furthermore, to eliminate the need to provide in a separate manner a mechanism for preventing single crystal droppage, and to enhance reliability and durability by not adversely affecting a clean environment during single crystal growth. The arm has a mating member, which mates with the mating portion of a single crystal, and does not allow the single crystal to drop when pulling the single crystal. The arm undergoes an attitude change to a mating position in accordance with moving a circular motion having a circular motion support point as the center of the circular motion. And, when the single crystal mating portion is formed, the arm undergoes an attitude change, arriving at a position, at which the arm mating member is capable of mating with the mating portion of the single crystal. And then, when mated to the single crystal mating portion, the arm is raised in synch with the single crystal pulling operation. At this time, the arm is raised, maintaining a vertical attitude.

Single crystal pulling apparatus and droppage preventing device

Detecting section detects joint angles and the relative angle of rotation from a plurality of rotatable operating tools mounted on a single mobile platform of a construction machine. Interference distance calculator, having recorded predetermined point positions for each operating tool, derives the distances between the plurality of operating tools on the basis of the detection results and the point positions, and calculates the shortest approach distance from these distances. If this shortest approach distance is less than a prescribed set distance, anti-interference controller issues a warning to alarm via the output controller, and it outputs anti-interference control to hydraulic control section CC such that the approaching tool is halted or slowed down, or the velocity of the operating tool being approached is matched to that of the approaching tool depending on the set mode.

Anti-interference device for construction machine

To prevent toppling of a construction machine where a plurality of operating tools are provided on a single mobile platform, a control section detects the cylinder axial forces, joint angles and relative angle of rotation for a plurality of operating tools provided rotatably on a single mobile platform, and a moment calculator calculates a composite moment for the plurality of operating tools on the basis of these detection results and further calculates a stability value relating to toppling, from this composite moment and a reference moment. If the calculated stability value is less than a reference value, an anti-toppling controller issues an alarm from the alarm via an output controller and halts the operation of the plurality of operating tools, or alternatively, if the operation of the operating lever input via the lever gain calculator will cause the stability to fall below a set value, it controls a hydraulic control section such that the action of the operating tool corresponding to this operation is prohibited. By allowing the operating tool located on the base where the control section and hydraulic control section are installed to be detected by electrical signals, but using pressure signals only for the other operating tools, the need for electrical swivels between the plurality of devices is removed.

Anti-toppling device for construction machine

A working machine control device for construction machinery provided with a plurality of joined working arms, an attachment mounted to the leading end of the working arms and a plurality of actuators for driving the working arms and the attachment, includes a function to adjust a pushing force between the attachment and a working plane by automatically controlling at least one of the actuators. The control device also includes a load detecting unit for detecting a load applied from the working plane to the attachment, working machine posture detecting devices for detecting postures of the working arms and the attachment and a computing unit for computing the pushing force between the attachment and the working plane on the basis of output values from the load detecting unit and the working machine posture detecting devices. The computing unit outputs a component of the pushing force in a direction perpendicular to the working plane. A target value setting unit is also provided for setting a target of a component of a pushing force suitable for working in the direction perpendicular to the working plane. A drive control unit automatically controls at least one of the plurality of actuators so that the computed result of the computing unit agrees with the target value set by the target value setting unit.

Growing community of inventors

Hiratsuka, Japan

Naritoshi Ohtsukasa