JP5219919B2 - DPF self-regeneration device for construction machinery - Google Patents

Description

  The present invention relates to a DPF (Diesel Particulate Filter) self-regeneration device for a construction machine, and more particularly to a DPF self-regeneration device for a construction machine capable of performing DPF self-regeneration processing during warm-up operation of an engine.

Conventionally, a construction machine such as a hydraulic excavator has an upper swing body mounted on a lower traveling body and an engine installed at the rear of the upper swing body. The exhaust system of the engine is provided with a DPF which is an exhaust gas aftertreatment device, and the DPF adsorbs and captures particulate matter (Particulate Matter) mainly composed of carbon contained in the exhaust gas. Collect and purify the exhaust gas.

  The particulate matter accumulates in the DPF along with the exhaust gas purification treatment, and the output efficiency of the engine decreases when the amount of particulate matter deposited reaches a certain value. For this reason, in order to burn and remove the particulate matter, it is necessary to perform an operation control so that the combustion temperature of the engine rises and to perform a regeneration process of the DPF (see, for example, Patent Document 1).

JP 2003-129900 A

  By the way, in DPF self-regeneration processing, it is necessary to carry out incineration removal of particulate matter for a certain period of time according to the amount of accumulated particulate matter, but in the conventional technology, DPF self-regeneration processing is performed while the construction machine is in operation. Therefore, there is a problem that the operation efficiency of the construction machine is lowered by that amount.

  Therefore, there is a technical problem to be solved in order to efficiently perform the self-regeneration processing of the DPF without reducing the operation efficiency of the construction machine, and the present invention aims to solve this problem. .

The present invention has been proposed to achieve the above object, and the invention according to claim 1 is directed to an engine key in a DPF self-regeneration device for a construction machine having a DPF that collects particulate matter in exhaust gas. Engine key state detecting means for detecting the on / off state of the engine, and clogging determining means for determining the degree of clogging of the DPF based on the operating state of the engine when the engine key is turned on and the automatic warm-up operation is performed. A regeneration control means for starting self-regeneration processing of the DPF when the DPF is clogged, and ending the automatic warm-up operation while ending the self-regeneration processing when the clogged state is resolved ; A DPF self-reproducing device for a construction machine is provided.

According to this configuration, when the engine key is turned on to perform the automatic warm-up operation of the engine, the engine key on state signal is transmitted from the engine key state detection unit to the clogging determination unit. Then, the clogging determining means determines the degree of clogging of the DPF based on the operating state of the engine. As a result, when the DPF is clogged, the regeneration control means implements the DPF self-regenerating device.
Further, when the self-regeneration process is started and the clogged state is resolved, the self-regeneration process is controlled through the regeneration control means and the automatic warm-up operation is terminated. can do.

The invention according to claim 2 is characterized in that the regeneration control means controls to reduce the intake amount and / or the exhaust amount of the engine when the regeneration process of the DPF is performed. A DPF self-regeneration device for construction machinery is provided.

  According to this configuration, when the DPF regeneration process is performed, the intake air amount and / or the exhaust air amount of the engine is reduced, so that the exhaust temperature of the engine rises and the particulate matter accumulated in the DPF is efficiently incinerated and removed. Is done.

According to the first aspect of the present invention, since the DPF self-regeneration process is performed using the automatic warm-up operation time of the engine before the construction machine is operated, it is necessary to perform the DPF self-regeneration process during the operation of the construction machine. Therefore, the operation efficiency of the construction machine can be improved accordingly.

  According to the second aspect of the present invention, when the DPF regeneration process is performed, the particulate matter deposited on the DPF can be efficiently incinerated and removed by raising the exhaust temperature of the engine. Thus, the DPF regeneration processing time can be shortened.

1 is a plan view conceptually illustrating a hydraulic excavator including a DPF self-reproducing device according to an embodiment of the present invention. The block diagram explaining the structure of the body controller which concerns on this invention. The flowchart which shows an example of the process sequence of the DPF self-regeneration apparatus which concerns on this invention.

In order to achieve the object of executing DPF self-regeneration processing without lowering the operation efficiency of a construction machine, the present invention provides a DPF self-container for a construction machine equipped with a DPF that collects particulate matter in exhaust gas. In the playback device, engine key state detection means for detecting the on / off state of the engine key, and when the engine key is turned on and the warm-up operation is performed, the degree of clogging of the DPF is determined based on the operating state of the engine. This is realized by including clogging determination means and regeneration control means for controlling self-regeneration processing of the DPF when the DPF is clogged.

  A preferred embodiment of the present invention will be described below with reference to FIGS. This embodiment is applied to a construction machine that can automatically control the self-regeneration processing of the DPF.

  FIG. 1 is a plan view showing a hydraulic excavator as a construction machine according to the present embodiment. In the figure, reference numeral 1 denotes an upper swing body that is pivotably mounted on a lower traveling body (not shown), and a work machine 2 including a boom, an arm, and a bucket is provided at the front center portion of the upper swing body 1. It is pivotally attached so that it can turn up and down. Further, a cab 3 is provided on one front side of the upper swing body 1, and an operator seat 4 is disposed in the cab 3. Furthermore, a monitor 5 is installed in front of the operator seat 4, and a machine controller 6 is connected to the monitor 5.

  A diesel engine 7 having a fuel injection device is mounted at the rear of the upper swing body 1, and a hydraulic pump 8 is connected to the output shaft of the diesel engine 7. The diesel engine 7 is provided with various detection means such as an engine key state detection means 9 for detecting the on / off state of the engine key and an engine speed detection means (not shown). These various detection means are connected to the body controller 6 via an engine control device (engine controller) (not shown).

An intake pipe 10 and an exhaust pipe 11 are connected to the diesel engine 7, and an intake throttle valve 12 and an exhaust throttle valve 13 are interposed in the middle of the intake pipe 10 and the exhaust pipe 11. The intake throttle valve 12 and the exhaust throttle valve 13 are throttled by the body controller 6.

  Further, a DPF 14 is installed on the downstream side of the exhaust pipe 11. The DPF 14 adsorbs and collects particulate matter (hereinafter referred to as “PM”) contained in the exhaust gas, and purifies the exhaust gas.

  The DPF 14 is formed of a honeycomb-structured ceramic cylinder having a large number of small holes, and an oxidation catalyst such as platinum is supported on the inner wall surface of the small holes. Further, a differential pressure detecting means 15 is attached to the DPF 14, and the differential pressure detecting means 15 is a differential pressure before and after the DPF 14 in the exhaust system, that is, a difference between an exhaust pressure upstream of the DPF 14 and an exhaust pressure downstream of the DPF 14. Is always detected.

  Further, the PM accumulates in the DPF 14 as the PM in the exhaust gas is adsorbed and collected. When the amount of PM accumulated reaches a predetermined value (limit accumulation value or self-regeneration start value), the aircraft A self-regeneration processing command signal is output from the controller 6, and the self-regeneration processing of the DPF 14 is automatically performed.

  FIG. 2 shows a configuration example of the body controller 6. As shown in the figure, the body controller 6 is mainly composed of a microcomputer, and includes an input unit 61, a storage unit 62, a timing unit 63, a clogging determination unit 64, a regeneration control unit 65, a valve throttle control unit 66, and an output unit 67. Etc. An engine key on / off state signal is input from the engine key state detection unit 9 to the input unit 61, and a differential pressure signal before and after the DPF 14 is input from the differential pressure detection unit 15.

  The storage means 62 stores map data indicating the relationship between the detection result of the differential pressure detection means 15 and the degree of clogging (PM deposition amount) of the DPF 14, and information such as a self-regeneration processing program of the DPF 14. . The time measuring means 63 measures the self-regeneration processing time and the like.

  Further, the clogging determination means 64 is based on the differential pressure signal from the differential pressure detection means 15 when the on-state signal is output from the engine key state detection means 9 before operating the machine of the hydraulic excavator. It is determined whether or not the DPF 14 is clogged while referring to the map data. In this case, the determination result of the clogged state of the DPF 14 is transmitted from the output unit 67 to the monitor 5 and is displayed on the monitor 5 in real time.

  Further, the regeneration control means 65 outputs a self-regeneration command signal to the self-regeneration drive means 16 when the DPF 14 is clogged, and causes the DPF 14 to perform self-regeneration processing. Further, the valve throttle control means 66 outputs a valve throttle command signal to the intake throttle valve 12 and / or the exhaust throttle valve 13 when the DPF 14 is clogged, and the intake throttle valve 12 and / or the exhaust throttle valve 13. Control to reduce the valve opening amount.

  Next, the operation of the DPF self-regeneration processing apparatus of this embodiment will be described in detail with reference to FIG. First, before operating the machine operation of the hydraulic excavator, the operator turns on the engine key to perform the warm-up operation of the diesel engine 7. At that time, an engine key-on signal is output from the engine key state detection means 9, and the engine key-on signal is transmitted to the machine controller 6 via the engine control device (step S1).

At this time, a differential pressure signal is input from the differential pressure detection means 15 to the machine controller 6, and based on the differential pressure signal, the clogging determination means 64 refers to the map data to determine whether or not the DPF 14 is clogged. Is determined (step S2). As a result, when the DPF 14 is not clogged, the warm-up operation is executed for a predetermined time (step S3). Then, when the warm-up operation is finished, the work machine of the hydraulic excavator is subsequently operated (Steps S4 and S5).

  On the other hand, when the clogging determination means 64 determines that the DPF 14 is clogged, a self-regeneration command signal is output from the regeneration control means 65 to the self-regeneration drive means 16, and self-regeneration processing of the DPF 14 is performed. (Step S6). In this self-regeneration process, for example, the diesel engine 7 is automatically switched to a high-load operation and the exhaust temperature of the diesel engine 7 is raised, so that PM accumulated in the DPF 14 is quickly burned and removed.

  In the present embodiment, when the self-regeneration process of the DPF 14 is performed, a valve throttle command signal is output from the valve throttle control means 66 to the intake throttle valve 12 and / or the exhaust throttle valve 13, and the intake throttle valve 12 and / or the exhaust throttle Control is performed so that the valve opening amount of the valve 13 is reduced. Thereafter, when the clogged state of the DPF 14 is resolved after a lapse of a predetermined time, the self-regeneration processing control is canceled and the warming-up operation is terminated (step S7), and then the operation of the hydraulic excavator in step S5 is started.

According to the present invention as the ordination, when performing the warming up of the diesel engine 7, when the DPF clogging signal from clogging determination means 64 is output by the reproduction control unit 65 self-renewal process of DPF14 is performed The Thus, since the DPF 14 self-regeneration processing is performed using the warm-up operation time of the diesel engine 7 before the hydraulic excavator is operated, it is not necessary to perform the DPF 14 self-regeneration processing during the operation of the hydraulic excavator. The operating efficiency of the hydraulic excavator is improved accordingly.

  Further, when the regeneration process of the DPF 14 is performed, the intake air amount and / or the exhaust gas amount of the diesel engine 7 is reduced, so that the exhaust temperature of the diesel engine 7 rises. Therefore, PM deposited on the DPF 14 can be efficiently removed by incineration, and the regeneration processing time of the DPF 14 is greatly shortened.

  It should be noted that the present invention can be variously modified without departing from the spirit of the present invention, and the present invention naturally extends to the modified ones.

  The present invention can also be applied to a construction machine or a vehicle that does not have a function of automatically controlling the self-regeneration processing of the DPF.

6 Airframe controller 7 Diesel engine 9 Engine key state detection means 10 Intake pipe 11 Exhaust pipe 12 Intake throttle valve 13 Exhaust throttle valve 14 DPF
15 Differential pressure detection means 64 Clogging judgment means 65 Regeneration control means 66 Valve throttle control means

Claims (2)

In a DPF self-regeneration device for a construction machine equipped with a DPF that collects particulate matter in exhaust gas, an engine key state detection means for detecting an on / off state of the engine key, and an automatic warm-up operation when the engine key is turned on Is performed, the clogging determining means for determining the degree of clogging of the DPF based on the operating state of the engine, and when the DPF is clogged, the self-regeneration process of the DPF is started, and the clogged state is A DPF self-regeneration device for a construction machine, comprising: a regeneration control means for controlling so as to terminate the automatic warm-up operation while terminating the self-regeneration process when resolved 2. The DPF self-regeneration device for a construction machine according to claim 1, wherein the regeneration control means controls to reduce the intake air amount and / or the exhaust air amount of the engine when the DPF self-regenerates.

Images