Yanmar Power Technology Co., Inc.

Yanmar Holdings Co., Ltd.

Masahiro Itani

Hideo Shiomi

Katsunari Jonouchi

Keiji Kunisawa

Takayuki Shirouzu

Shunsuke Mori

Hiroshi Matsuyama

Yuji Kawabata

Junichi Niimi

An engine includes a control unit that controls the EGR valve. The control unit selects a predetermined control mode from at least a first mode, a second mode, and a third mode according to at least an engine speed and a fuel injection amount, and controls the EGR valve in the selected control mode. The first mode is a control mode in which the EGR valve is fully closed. The second mode is a control mode in which the opening degree of the EGR valve is adjusted according to the operation state of the engine. The third mode is a control mode in which an ON period in which the opening degree of the EGR valve is adjusted according to the operation state of the engine and an OFF period in which the EGR valve is fully closed are repeated.

Engine

A control device is configured to estimate a soot deposition amount (PM deposition amount) in a DPF for an exhaust purification device that is configured to purify exhaust of a diesel engine using the DPF, and determine a regeneration timing for the diesel engine based on the estimated PM deposition amount. As a technique of determining the regeneration timing, the control device employs a first determination technique of detecting that the PM deposition amount is a first threshold or more and a state in which the PM deposition amount is the first threshold or more has continued for a first predetermined time and a second determination technique of detecting that the PM deposition amount is a second threshold (>the first threshold) or more and a state in which the PM deposition amount is the second threshold or more has continued for a second predetermined time.

Particle deposition amount estimation device and exhaust purification system

An engine control device controls an engine provided with an EGR device. The engine control device is provided with an abnormality determining unit, a restricted operation unit, and a restriction released operation unit. The abnormality determining unit determines whether an abnormality has arisen in the EGR device. The restricted operation unit performs restricted operation in which some functions of the engine are restricted, if the abnormality determining unit has determined that an abnormality has arisen in the EGR device. If a manipulation to release the restricted operation has been performed, the restriction released operation unit switches from restricted operation to restriction released operation in which the restrictions on some of the functions of the engine are released, and performs said restriction released operation.

Engine control device

A control device for a hydraulic machine such as a revolving excavator work machine in which a load-sensing pump control system is adopted The control device prevents variation in pump control characteristics among a plurality of hydraulic machines and also prevents variation in the operating speed of individual drive units in the hydraulic machines The control device; and it is configured to perform, by using a storage unit and a calculation unit outside the hydraulic machine, a process of causing an engine rotation state and a hydraulic actuator operation state to be specific states and calculating a correction rate for a control output value of an electromagnetic proportional valve for generating a control pressure, based on detection of an error in the flow rate of a hydraulic pump or its substitute numerical value such as the rotational speed and the like of a traveling motor which is easily detectable from outside.

Control device for hydraulic machine

A control device for a hydraulic machine such as a revolving excavator work machine having a structure that can cope with such an engine output decreasing environment as a work under a low atmospheric pressure at a high altitude without generating noise caused by engine rotation number increase. The control device corrects a control output value to be applied to an electromagnetic proportional valve for load-sensing valve control in a load-sensing type pump control system, based on a detected state quantity related to the engine output decreasing environment. When an engine speed-sensitive pump control system is adopted, a control output value generated based on a detected decrease in the actual engine rotation number is combined with a control output value generated by the load-sensing type pump control system.

An engine unit including a heater provided in a blow-by gas returning path for returning a blow-by gas that leaks out from a combustion chamber of an engine to an intake path. The heater is electrically connected to a controller of the engine through wiring harnesses. The controller is configured to, while controlling energization of the heater, perform an abnormality detection on the wiring harness based on a magnitude of current flowing to the wiring harness during energization of the heater, and perform an abnormality detection on the heater and the wiring harnesses based on a magnitude of voltage applied to the wiring harness located downstream from the heater during non-energization of the heater.

Growing community of inventors

Osaka, Japan

Masahiro Itani