Exhaust purifying device

Patent metadata

Field	Value
Publication number	US-9708955-B2
Application number	US-201515026505-A
Country	US
Kind code	B2
Filing date	Nov 25, 2015
Priority date	Nov 25, 2015
Publication date	Jul 18, 2017
Grant date	Jul 18, 2017

Abstract

An exhaust purifying device includes a throttle valve, a DOC device, an SCR device, a fuel injector, an inlet temperature sensor, an outlet temperature sensor, and a controller. The controller includes a heatup-control execution control unit configured to perform a regeneration treatment for removing a urea deposit when a predetermined heatup control execution condition is met, and a condition judgment unit configured to judge whether or not the first condition is met during the regeneration treatment by the heatup control.

First claim

The invention claimed is:

1. An exhaust purifying device comprising:
a throttle valve provided in a channel for an exhaust gas discharged from an engine to flow;
a diesel oxidation catalyst device disposed downstream of the throttle valve;
a selective catalytic reduction device disposed downstream of the diesel oxidation catalyst device;
a fuel injector configured to inject a fuel at an upstream of the diesel oxidation catalyst device;
an inlet temperature sensor configured to measure an inlet temperature of the diesel oxidation catalyst device;
an outlet temperature sensor configured to measure an outlet temperature of the diesel oxidation catalyst device; and
a controller that is configured to receive temperature data measured by the inlet temperature sensor and the outlet temperature sensor and is configured to control the throttle valve and the fuel injector, wherein
the controller comprises:
a heatup-control execution control unit configured to control the throttle valve and the fuel injector to raise a temperature of the injected fuel to perform a regeneration treatment by a heatup control to remove a urea deposit deposited in the channel when a predetermined heatup control execution condition is met; and
a condition judgment unit configured to judge whether or not a first condition is met during the regeneration treatment by the heatup control, the first condition being met when a first cumulative time obtained by cumulating a time in which a measured temperature of the outlet temperature sensor is equal to or higher than a regeneration judgment temperature is less than a first judgment time and an elapsed time after starting the regeneration treatment by the heatup control reaches or exceeds a second judgment time.

2. An exhaust purifying device comprising:
a throttle valve provided in a channel for an exhaust gas discharged from an engine to flow;
a diesel oxidation catalyst device disposed downstream of the throttle valve;
a selective catalytic reduction device disposed downstream of the diesel oxidation catalyst device;
a fuel injector configured to inject a fuel at an upstream of the diesel oxidation catalyst device;
an inlet temperature sensor configured to measure an inlet temperature of the diesel oxidation catalyst device;
an outlet temperature sensor configured to measure an outlet temperature of the diesel oxidation catalyst device; and
a controller that is configured to receive temperature data measured by the inlet temperature sensor and the outlet temperature sensor and is configured to control the throttle valve and the fuel injector, wherein
the controller comprises:
a heatup-control execution control unit configured to control the throttle valve and the fuel injector to raise a temperature of the injected fuel to perform a regeneration treatment by a heatup control to remove a urea deposit deposited in the channel when a predetermined heatup control execution condition is met; and
a condition judgment unit configured to judge whether or not a second condition is met during the regeneration treatment by the heatup control, the second condition being met when a first cumulative time obtained by cumulating a time in which a measured temperature of the outlet temperature sensor is equal to or higher than a regeneration judgment temperature is less than a first judgment time and a second cumulative time obtained by cumulating a time in which the measured temperature of the outlet temperature sensor is less than the regeneration judgment temperature reaches or exceeds a third judgment time.

3. An exhaust purifying device comprising:
a throttle valve provided in a channel for an exhaust gas discharged from an engine to flow;
a diesel oxidation catalyst device disposed downstream of the throttle valve;
a selective catalytic reduction device disposed downstream of the diesel oxidation catalyst device;
a fuel injector configured to inject a fuel at an upstream of the diesel oxidation catalyst device;
an inlet temperature sensor configured to measure an inlet temperature of the diesel oxidation catalyst device;
an outlet temperature sensor configured to measure an outlet temperature of the diesel oxidation catalyst device; and
a controller that is configured to receive temperature data measured by the inlet temperature sensor and the outlet temperature sensor and is configured to control the throttle valve and the fuel injector, wherein
the controller comprises:
a heatup-control execution control unit configured to control the throttle valve and the fuel injector to raise a temperature of the injected fuel to perform a regeneration treatment by a heatup control to remove a urea deposit deposited in the channel when a predetermined heatup control execution condition is met; and
a condition judgment unit configured to judge whether or not a first condition or a second condition is met during the regeneration treatment by the heatup control, the first condition being met when a first cumulative time obtained by cumulating a time in which a measured temperature of the outlet temperature sensor is equal to or higher than a regeneration judgment temperature is less than a first judgment time and an elapsed time from starting the regeneration treatment by the heatup control reaches or exceeds a second judgment time, the second condition being met when a first cumulative time obtained by cumulating a time in which a measured temperature of the outlet temperature sensor is equal to or higher than the regeneration judgment temperature is less than a first judgment time and a second cumulative time obtained by cumulating a time in which the measured temperature of the outlet temperature sensor is less than the regeneration judgment temperature reaches or exceeds a third judgment time.

4. The exhaust purifying device according to claim 1 , wherein
a judgment result of the condition judgment unit is notified when the condition judgment unit judges that the first condition is met.

5. The exhaust purifying device according to claim 1 , wherein
the controller comprises: a stationary manual regeneration execution control unit that is configured to control the throttle valve and the fuel injector to raise the temperature of the injected fuel to perform a regeneration treatment by a stationary manual regeneration treatment to remove the urea deposit deposited in the channel upon detecting an execution operation for the regeneration treatment by an operator.

6. The exhaust purifying device according to claim 1 , wherein
the controller comprises: a stationary manual regeneration execution control unit that is configured to control the throttle valve and the fuel injector to raise the temperature of the injected fuel to perform a regeneration treatment by a stationary manual regeneration treatment to remove the urea deposit deposited in the channel upon detecting an execution operation for the regeneration treatment by an operator, and
when the condition judgment unit judges that the first condition is met, the heatup-control execution control unit continues the regeneration treatment by the heatup control until the execution operation for the regeneration treatment by the operator is detected.

7. The exhaust purifying device according to claim 2 , wherein
when the condition judgment unit judges that the second condition is met, the heatup-control execution control unit stops the regeneration treatment by the heatup control.

8. The exhaust purifying device according to claim 1 , further comprising a notification unit configured to notify an operator of a judgment result of the condition judgment unit, wherein
the controller comprises:
a stationary manual regeneration execution control unit that is configured to control the

Assignees

• Komatsu Mfg Co Ltd

Inventors

• Ito Akira
• Miki Akihiro
• Oomori Takeo
• Kimura Mitsuyoshi

Classifications

• F01N2560/026

  for measuring or detecting NOx · CPC title

• F01N3/206

  Adding periodically or continuously substances to exhaust gases for promoting purification, e.g. catalytic material in liquid form, NOx reducing agents · CPC title

• F01N2900/1404

  Exhaust gas temperature · CPC title

• F01N2560/06

  the means being a temperature sensor · CPC title

• F01N3/106

  Auxiliary oxidation catalysts · CPC title