JP2019015191A - Abnormality notification device, work vehicle mounted with the device and forklift - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a first remaining time until a limit for reducing an engine output to a predetermined output is started and a second remaining time until a limit for reducing an engine speed is started when an abnormality occurs. Provide an abnormality notification device in which is displayed. An abnormality notification device 70 includes a detection unit 91 that detects an abnormality in an exhaust gas purification device 50, a timekeeping unit 92 that clocks a first standby time and a second standby time, and a first standby time by the timekeeping unit. Executes the first output limit that limits the engine output to the first limit value based on the completion of the timekeeping, and sets the engine output from the first limit value based on the completion of the timekeeping of the second standby time of the timekeeping part. The output limit unit 93 that executes the second output limit that limits to the second limit value, which is also small, and the notification of the first remaining time, which is the remaining time of the first standby time, are notified based on the detection of the abnormality by the detection unit 91. The notification unit 10 is provided to start and start notifying the second remaining time, which is the remaining time of the second waiting time, based on the completion of the time counting of the first waiting time. [Selection diagram] Fig. 1

Description

  The present invention relates to an abnormality notification device, and in particular, includes a urea SCR (Selective Catalytic Reduction) device that purifies nitrogen oxide (NOx) contained in exhaust gas from a diesel engine mounted on a work vehicle such as a forklift. The present invention relates to an abnormality notification device for an exhaust gas purification device. The present invention also relates to a work vehicle and a forklift equipped with such an abnormality notification device.

  2. Description of the Related Art In a work vehicle such as a forklift equipped with a diesel engine, an exhaust gas purification device including a particulate collection filter called a diesel particulate filter (DPF) and a urea SCR device is used to purify the exhaust gas of the diesel engine. Are known. In the urea SCR device, ammonia produced by hydrolysis of urea water and NOx contained in the exhaust gas of the diesel engine react chemically to produce nitrogen and water, thereby removing NOx.

  In Patent Document 1, when an abnormality of the exhaust gas purifying device is detected, the engine output is limited, the output limit is set so that the engine output becomes the lowest after a predetermined time elapses, and the engine output is maximized. A work vehicle that reports a predetermined time until the output limit to be lowered is started (Patent Document 1).

JP 2012-145083 A

  However, in the exhaust gas purification system mounted on the work vehicle disclosed in Patent Document 1, after the advance notice of operation restriction, the time required until the start of restriction is displayed on the screen, the time is updated as needed, and the predetermined time has elapsed. Then, only operation restriction is performed. Therefore, since the engine output limit accompanying the abnormality detection is started without notifying the operator, the operator may feel anxiety.

(1) The abnormality notification device according to the first aspect of the present invention includes a detection unit that detects an abnormality of the exhaust gas purification device, a time measurement unit that measures the first standby time and the second standby time, and the time measurement unit. Based on completion of timing of the first waiting time, a first output restriction is performed to limit the output of the engine to a first limit value, and engine output is controlled based on completion of timing of the second waiting time of the timing section. An output limiter that executes a second output limit that limits to a second limit value that is smaller than the first limit value, and a notification of the first remaining time that is the remaining time of the first standby time, And a notification unit that starts notification of the second remaining time, which is the remaining time of the second waiting time, based on the completion of timing of the first waiting time. .
(2) The abnormality notification device according to the second aspect of the present invention is the abnormality notification device according to the first aspect, wherein the detection unit detects a second abnormality in addition to the first abnormality which is the abnormality, and the notification The unit reports the first remaining time based on the first abnormality, and reports the second remaining time based on the second abnormality.
(3) The abnormality notification device according to the third aspect of the present invention is the abnormality notification device according to the first or second aspect, wherein the notification unit notifies the first remaining time and / or the second remaining time. At this time, information on the first output restriction and / or information on the second output restriction are displayed together.
(4) In the abnormality notification device according to any one of the first to third aspects, the notification unit of the abnormality notification device according to the fourth aspect of the present invention is predetermined when the notification unit does not detect the abnormality. When information different from the first remaining time and / or the second remaining time is notified to a position and the abnormality is detected, the first remaining time and / or the second remaining time is detected at the predetermined position. Notification.
(5) The abnormality notification device according to a fifth aspect of the present invention is the abnormality notification device according to the first aspect, wherein the exhaust gas purification device is a urea water SCR device, and the abnormality is detected by the detection unit by the urea. This corresponds to a case where it is detected that the amount of urea water in the water SCR device is equal to or less than a predetermined amount.
(6) The abnormality notification device according to the sixth aspect of the present invention is the abnormality notification device according to the second aspect, wherein the exhaust gas purification device is a urea water SCR device, and the first abnormality is detected by the detection unit. This corresponds to a case where the amount of urea water in the urea water SCR device is detected to be the first predetermined amount, and the second abnormality is caused by the detection unit to determine the amount of urea water in the urea water SCR device. This corresponds to a case where it is detected that the second predetermined amount is smaller than the first predetermined amount.
(7) A work vehicle according to a seventh aspect of the present invention includes a diesel engine, an exhaust gas purification device that purifies exhaust gas of the diesel engine, and an abnormality notification device according to any one of the first to sixth aspects. With.
(8) A forklift according to an eighth aspect of the present invention includes a diesel engine, an exhaust gas purification device having at least a urea water SCR device that purifies exhaust gas of the diesel engine, and an abnormality notification according to the fifth or sixth aspect. Device.

  According to the present invention, when an abnormality occurs in the exhaust gas purification device, the first remaining time until the first output limit for limiting the output of the engine with the first limit value is started, and the first limit value 2nd remaining time until the 2nd output restriction which restricts with the 2nd limit value smaller than is started is displayed. Therefore, the operator can recognize each time until the two kinds of output restrictions are started in accordance with the abnormality of the exhaust gas purification device, and can perform an appropriate process within these times.

It is the schematic which shows the structure of the work vehicle carrying the abnormality alerting device which concerns on embodiment of this invention. In the abnormality alarm device concerning an embodiment of the invention, it is a key map showing the example of a display of the information about the 1st output restriction and the 1st remaining time. In the abnormality alarm device concerning an embodiment of the invention, it is a key map showing the example of a display of the information about the 2nd output restriction and the 2nd remaining time. It is a flowchart explaining the process in the abnormality alerting device which concerns on the 1st Embodiment of this invention. It is a flowchart explaining the process in the abnormality alerting device which concerns on the 2nd Embodiment of this invention. FIG. 11 is a conceptual diagram illustrating a display example of information related to a first output limit, a first remaining time, a second output limit, and a second remaining time in an abnormality notification device according to a modification of the present invention. In the abnormality notification device according to the modified example of the present invention, it is a conceptual diagram showing a display example in which the display relating to the first output restriction and the first remaining time is displayed instead of the information notified before the abnormality detection, a) is a conceptual diagram showing the display contents before displaying information on the first output limit and the first remaining time, and (b) is switched to information on the first output limit and the first remaining time. It is a conceptual diagram which shows the state currently displayed.

(First embodiment)
Hereinafter, an abnormality notification device according to a first embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic diagram of a system configuration of a work vehicle 100 equipped with an abnormality notification device 70 according to the present embodiment. An exhaust gas purification device 50 is mounted on a work vehicle 100 (for example, a forklift) on which an abnormality notification device 70 according to the first embodiment is mounted. The exhaust gas purification device 50 is, for example, as shown in FIG. And an oxidation catalyst 2, a diesel particulate filter (DPF) device 3, a urea selective catalyst reduction system (SCR device) 4, and an oxidation catalyst 5. As shown in FIG. 1, the work vehicle 100 equipped with the abnormality notification device 70 includes an engine 1, an exhaust gas purification device 50, a urea water tank 6, a urea water pump 7, a urea water sensor 8, a control unit 9, a notification. The unit 10 and the operation unit 11 are provided at least.

In the exhaust gas purifying device 50, the oxidation catalyst 2 into NO ₂ by oxidizing a part of NO contained in the exhaust gas. The DPF device 3 disposed downstream of the oxidation catalyst 2 removes particulate matter (PM) contained in the exhaust gas. The SCR device 4 disposed downstream of the DPF device 3 chemically reacts ammonia and NOx produced by hydrolysis of urea water injected by the urea water pump 7 with the exhaust gas purified by the DPF device 3. Thus, NOx contained in the exhaust gas is purified to nitrogen and water. The oxidation catalyst 5 disposed downstream of the SCR device 4 oxidizes the remaining ammonia that is not consumed in the chemical reaction in the SCR device 4.

  The control unit 9 includes a detection unit 91, a time measuring unit 92, and an output limiting unit 93. The work vehicle 100 on which the abnormality notification device 70 is mounted is, for example, a work vehicle such as a forklift. Various information is input to the control unit 9 from the engine 1, the urea water sensor 8, the notification unit 10, the operation unit 11, and the like. For example, the control unit 9 receives information from the engine 1 such as the number of revolutions and the temperature of the cooling water, the urea water sensor 8 from the urea water amount, the information related to the display content from the notification unit 10, and the like from the operation unit 11. Information on the operation state of pedals and switches is input.

  The control unit 9 performs control so that the work vehicle 100 is operated in accordance with the operation of the operation unit 11 by the operator, or an image indicating the operation state or the state of the work vehicle 100 is displayed on the notification unit 10. The exhaust gas discharged from the engine 1 is purified via the exhaust gas purification device 50 and then discharged into the atmosphere.

  As described above, the SCR device 4 purifies NOx contained in the exhaust gas exhausted from the engine 1. A urea water supply pipe is provided so that the urea water stored in the urea water tank 6 is supplied into the exhaust gas introduced into the SCR device 4 by the urea water pump 7. The urea water pump 7 operates based on an instruction from the control unit 9 and supplies urea water from the urea water tank 6 to the SCR device 4. That is, urea water is injected by the urea water pump 7 into the exhaust gas purified by the DPF device 3 from the urea water injection nozzle disposed in the pipe line near the inlet of the SCR device 4. In the SCR device 4, the urea water is hydrolyzed to generate ammonia, and this ammonia and NOx contained in the exhaust gas chemically react with each other to change into nitrogen and water. The urea water tank 6 is provided with a urea water sensor 8, detects the amount of urea water stored in the urea water tank 6, and transmits the detected information to the control unit 9 detection unit 91.

  When the detection unit 91 detects that the urea water stored in the urea water tank 6 is less than a predetermined amount based on the information transmitted from the urea water sensor 8, the control unit 9 determines that the exhaust gas purification device 50 is desired. It is determined that the exhaust gas purification performance cannot be exhibited, that is, it is abnormal. Specifically, when the control unit 9 determines from the information transmitted from the urea water sensor 8 that the urea water stored in the urea water tank 6 is less than a predetermined amount, the time measuring unit 92 of the control unit 9 Start timing of the first waiting time. The first standby time refers to a time until the output limiting unit 93 of the control unit 9 starts a limit (first output limit) for reducing the output of the engine 1 to the first limit value. The control unit 9 controls the notification unit 10 to display the remaining time (first remaining time) of the first standby time. As an example of the first output restriction, it is conceivable that the output restriction is such that the maximum rotational speed of the engine 1 is suppressed to 70% of the allowable rotational speed. At this time, it is preferable that the control unit 9 controls the notifying unit 10 to display not only the information on the first remaining time but also information on the content of the first output restriction. In other words, it is preferable that the display be such that the operator can understand that the first remaining time is the time until the limit for reducing the output of the engine 1 to the first limit value is started.

  An example of the display of the first remaining time is shown in FIG. In FIG. 2, “Delate Lv 1” displayed on the upper left side in the display screen of the notification unit 10 represents information on the contents of the first output restriction, and the hourglass symbol displayed on the upper right side and “15 min” Represents that the time (first remaining time) until the first output restriction is executed is 15 minutes. In addition, the alerting | reporting part 10 is arrange | positioned in the work vehicle 100 with the operation part 11 in the position where the operator of the vicinity of a driver's seat is easy to visually recognize. You may comprise so that a part of operation part may be arrange | positioned at a display part.

  When the engine 1 is stopped and the operation of the work vehicle 100 is interrupted by the operator's operation while the first standby time is being measured, the time measurement of the first standby time by the timer unit 92 is interrupted, and the time value at that time is not illustrated. It is stored in a memory (storage unit). Thereafter, when the operator restarts the operation of the work vehicle 100 by starting the engine 1 again, the control unit 9 reads the time measured value of the first standby time stored in the memory, and the time measuring unit 92 receives the first standby time. Restart the time measurement from the read value. Thereby, when the operation is resumed, the notification unit 10 displays the first remaining time displayed on the notification unit 10 immediately before the operation is interrupted. The control unit 9 controls the notification unit 10 to display the first remaining time as a time counted down with the passage of time.

  When the timing of the first waiting time by the time measuring unit 92 is completed, the output limiting unit 93 of the control unit 9 restricts the engine 1 to a first output limitation that allows the engine 1 to rotate at a first limiting value. Do. In the forklift, engine control is performed in which the engine speed is increased or decreased according to the amount of depression of the accelerator pedal. Therefore, when the first output restriction is started, the output is restricted so that even if the operator depresses the accelerator pedal for a full stroke, the rotation speed does not increase beyond the rotation speed corresponding to the first output restriction (first limit value). Is done. When the amount of depression is below the rotation speed range corresponding to the first output restriction, the engine is operated at the number of revolutions corresponding to the depression amount. Therefore, when trying to raise the load placed on the fork to a predetermined height at high speed, or when the accelerator pedal is fully stroked to perform a sudden start operation with an empty load, the engine speed is Since the speed can be increased only to the rotation speed of the first output limit, the operator can experience an abnormal operation.

  When the time measurement of the first standby time is completed, the display of the first remaining time in the notification unit 10 displays, for example, zero. Alternatively, a message such as “output restriction will start” may be displayed. When the first output restriction is started, the output value of the first output restriction may be reduced with the passage of time.

  When the timing of the first standby time is completed, the time measuring unit 92 waits for a second time until a limit (second output limit) is set for setting the output (rotation speed) of the engine 1 to a low rotation speed (for example, idle rotation speed) Start timing time. The second standby time refers to a time until the output restriction unit 93 starts a restriction (second output restriction) for reducing the output of the engine 1 to the idle speed. Furthermore, the control unit 9 controls the notification unit 10 to display the remaining time (second remaining time) of the second standby time. At this time, it is preferable that the control unit 9 controls the notifying unit 10 to display not only the information on the second remaining time but also information on the content of the second output restriction. That is, it is preferable to display the second remaining time so that the operator can understand that the time until the limitation of rotating the engine 1 at the idle speed is started.

  An example of display of the second remaining time is shown in FIG. In FIG. 3, “Delate Lv 2” displayed on the upper left side in the display screen of the notification unit 10 represents information on the content of the second output restriction, and the hourglass symbol displayed on the upper right side and “5 min” Indicates that the time until the second output restriction is executed (second remaining time) is 5 minutes.

  When the engine 1 is stopped and the operation of the work vehicle 100 is interrupted by the operator's operation while the second standby time is being measured, the second standby time by the timer unit 92 is interrupted, and the time value at that time is stored in a memory (not shown). Stored. Thereafter, when the operator restarts the operation of the work vehicle 100 by starting the engine 1 again, the control unit 9 reads the time value of the second standby time stored in the memory, and the time measuring unit 92 receives the second standby time. Restart the time measurement from the read value. Thereby, when the operation is resumed, the notification unit 10 displays the second remaining time displayed on the notification unit 10 immediately before the operation is interrupted. When the time counting of the second standby time by the time measuring unit 92 is completed, the output limiting unit 93 of the control unit 9 performs a second output limitation for the engine 1 to rotate at the idle speed.

  When the timing of the second waiting time is completed, the display of the second remaining time in the notification unit 10 displays, for example, zero. Alternatively, a message such as “output limitation starts so as to drive at idle speed” may be displayed.

  Next, the abnormality notification process in the abnormality notification device 70 according to the first embodiment will be described with reference to the flowchart shown in FIG. In the processing procedure shown in FIG. 4, a program stored in a memory (not shown) is read and executed by the CPU.

  In step S <b> 1, the control unit 9 determines whether or not the urea water stored in the urea water tank 6 is below a predetermined amount based on the information transmitted from the urea water sensor 8. When it determines with the urea water not being less than predetermined amount, negative determination is made and step S1 is repeated. In this case, the control unit 9 corresponds to determining that no abnormality has occurred in the exhaust gas purification device 50. On the other hand, when it determines with urea water being less than predetermined amount, the control part 9 makes an affirmation determination and progresses to step S2. In this case, the control unit 9 corresponds to determining that an abnormality has occurred in the exhaust gas purification device 50.

  In step S2, the time measuring unit 92 starts measuring the first standby time (counting down). That is, the time measuring unit 92 starts measuring the first waiting time until the start of the restriction (that is, the first output restriction) for reducing the output of the engine 1 to a predetermined output (first restriction value). Moreover, the control part 9 controls the alerting | reporting part 10, displays the 1st remaining time which is the remaining time of a 1st waiting time, and progresses to step S3. In step S <b> 3, the control unit 9 determines whether the timing of the first waiting time by the timing unit 92 has been completed. If it is determined that the timing of the first waiting time has been completed, an affirmative determination is made and the process proceeds to step S4. If it is determined that the timing of the first waiting time has not been completed, a negative determination is made and the process returns to step S2.

  In step S <b> 4, the output restriction unit 93 executes a first output restriction on the engine 1 that reduces the output to a predetermined rotational speed (first restriction value). In addition, the time measuring unit 92 starts measuring the second standby time (countdown). That is, the time measuring unit 92 starts measuring the second waiting time until the start of the limit (that is, the second output limit) for setting the output (rotation speed) of the engine 1 to the idle rotation speed (second limit value). To do. Furthermore, the control part 9 controls the alerting | reporting part 10, displays the 2nd remaining time which is the remaining time of a 2nd waiting time, and progresses to step S5.

  In step S <b> 5, the control unit 9 determines whether the timing of the second waiting time by the timing unit 92 has been completed. If it is determined that the timing of the second waiting time has been completed, an affirmative determination is made and the process proceeds to step S6. If it is determined that the timing of the second waiting time has not been completed, a negative determination is made and the process returns to step S4. In step S <b> 6, the output restriction unit 93 executes a second output restriction that controls the engine 1 to rotate at the idle speed.

According to said 1st Embodiment, the following effect is obtained.
The abnormality notification device 70 of the first embodiment includes a detection unit 91 that detects an abnormality of the exhaust gas purification device 50, for example, when the amount of urea water is equal to or less than a predetermined amount, a first waiting time, and a second waiting time. A timer unit 92 that counts the waiting time, and a first limiter that limits the output of the engine to a first limit value, for example, a rotational speed that is 70% of the permissible rotational speed, based on completion of timing of the first standby time by the time measuring part 92 A second output limit that executes output limitation and limits the output of the engine to a second limit value that is smaller than the first limit value, for example, the idling speed, based on completion of timing of the second waiting time of the timing unit 92. Is started based on the detection of the abnormality by the detecting unit 91, and the second remaining time of the second standby time is started. Notification of remaining time, timing of first waiting time And a notification unit 10 to start based on the completion. The notification unit 10 notifies the second remaining time based on the completion of the time measurement of the first standby time by the time measuring unit 92. The abnormality notification device 70 configured as described above has the following operational effects.

  In the work vehicle 100 equipped with the abnormality notification device 70, when the urea water stored in the urea water tank 6 falls below a predetermined amount based on information from the urea water sensor 8, the exhaust gas purification device 50 includes It is determined that an abnormality has occurred. When the occurrence of abnormality is determined, timing of the first waiting time is started and the first remaining time is notified. When the timing of the first waiting time is completed, the first output restriction is executed, the timing of the second waiting time is started, and the second remaining time is notified. When the timing of the second waiting time is completed, the second output restriction is executed. Thus, when an abnormality is detected, the operator can recognize the time until each of the first output restriction and the second output restriction is started without depending on his / her own operation. The abnormality of the exhaust gas purification device 50 can be dealt with without feeling uneasy. In other words, the operator can recognize each time until the two types of output restriction are started in accordance with the abnormality of the exhaust gas purification device 50, and can perform an appropriate process within these times.

(Second Embodiment)
The abnormality notification device used in the second embodiment is substantially the same as the abnormality notification device 70 described in the first embodiment with reference to FIG. In the first embodiment, the time measurement of the second standby time is started based on the completion of the time measurement of the first standby time. On the other hand, in the second embodiment, timing of the second standby time is started based on the information regarding the amount of urea water stored in the urea water tank 6 output from the urea water sensor 8. The display contents of the first remaining time and the second remaining time are the same as the contents described in the first embodiment.

  In the abnormality notification device 70 according to the second embodiment, the control unit 9 is less than the first predetermined amount and the first predetermined amount with respect to the urea water stored in the urea water tank 6 transmitted from the urea water sensor 8. It is determined whether the urea water is below each of the two levels of the second predetermined amount. The “first predetermined amount” corresponds to the “predetermined amount” in the first embodiment. If the urea water falls below the first predetermined amount but does not fall below the second predetermined amount, the controller 9 determines that the first abnormality has occurred in the exhaust gas purification device 50. Moreover, when less than the 2nd predetermined amount, the control part 9 determines with it being in a 2nd abnormality state.

  When it is determined by the control unit 9 that the first abnormality has occurred in the exhaust gas purification device 50, the time measuring unit 92 starts measuring the first standby time (counting down). Further, the control unit 9 controls the notification unit 10 to display the first remaining time. When the timing of the first waiting time by the timing unit 92 is completed, the output limiting unit 93 performs the first output control on the engine 1. If the control unit 9 determines that the second abnormality has occurred in the exhaust gas purifying device 50 during the execution of the first output control, the time measuring unit 92 starts measuring the second standby time (counting down). Further, the control unit 9 controls the notification unit 10 to display the second remaining time. When the timing of the second standby time by the timing unit 92 is completed, the output limiting unit 93 executes the second output control for the engine 1.

  As described above, the display of the first remaining time and the second remaining time is the same as the content described in the first embodiment. That is, it is preferable that the control unit 9 controls the notifying unit 10 to display not only the information on the first remaining time but also information on the content of the first output restriction. Similarly, it is preferable that the control unit 9 controls the notifying unit 10 to display not only the information on the second remaining time but also information on the content of the second output restriction.

  The case where the engine 1 is stopped and the operation of the work vehicle 100 is interrupted by the operation of the operator while the first standby time is being measured and the second standby time is being measured is described in the first embodiment. It is the same as the processing.

  Next, an abnormality notification process in the abnormality notification device 70 according to the second embodiment will be described with reference to the flowchart shown in FIG. In the processing procedure shown in FIG. 5, a program stored in a memory (not shown) is read and executed by the CPU.

  In step S <b> 11, the control unit 9 determines whether the urea water stored in the urea water tank 6 is below the first predetermined amount based on the information transmitted from the urea water sensor 8. If it is determined that the urea water is not below the first predetermined amount, a negative determination is made and step S11 is repeated. In this case, the control unit 9 corresponds to determining that no abnormality has occurred in the exhaust gas purification device 50. On the other hand, when it determines with urea water being less than the 1st predetermined amount, the control part 9 makes an affirmation determination and progresses to step S12.

  In step S <b> 12, the control unit 9 determines whether the urea water stored in the urea water tank 6 is less than the second predetermined amount based on the information transmitted from the urea water sensor 8. The second predetermined amount is set to be smaller than the first predetermined amount. If it is determined that the urea water is not less than the second predetermined amount, a negative determination is made and the process proceeds to step S13. In this case, the control unit 9 corresponds to determining that the first abnormality has occurred in the exhaust gas purification device 50. In step S12, when the control unit 9 determines that the urea water is below the second predetermined amount, it makes an affirmative determination and proceeds to step S16. In this case, the control unit 9 corresponds to determining that the second abnormality has occurred in the exhaust gas purification device 50.

  In step S13, that is, when the control unit 9 determines that the first abnormality has occurred in the exhaust gas purification device 50, the time measuring unit 92 starts measuring the first standby time (counting down). In other words, the time measuring unit 92 starts measuring the first standby time until the start of the limit for reducing the output of the engine 1 to a predetermined output (that is, the first output limit). Moreover, the control part 9 controls the alerting | reporting part 10, displays the 1st remaining time which is the remaining time of 1st waiting time, and progresses to step S14. In step S <b> 14, the control unit 9 determines whether the timing of the first waiting time by the timing unit 92 has been completed. If it is determined that the timing of the first waiting time has been completed, an affirmative determination is made and the process proceeds to step S15. If it is determined that the timing of the first waiting time has not been completed, a negative determination is made and the process returns to step S13. In step S15, the output restriction unit 93 performs a first output restriction for the engine 1 to reduce the output to a predetermined rotational speed (output), and returns to step S12.

  In step S <b> 12, when the control unit 9 determines that the amount of urea water is less than the second predetermined amount, that is, the control unit 9 indicates that the second abnormality has occurred in the exhaust gas purification device 50. If determined, an affirmative determination is made and the process proceeds to step S16. In step S <b> 16, the time measuring unit 92 starts measuring (counting down) the second standby time. That is, the time measuring unit 92 starts measuring the second standby time until the start of the limit (that is, the second output limit) for setting the output (rotation speed) of the engine 1 to the idle rotation speed. Moreover, the control part 9 controls the alerting | reporting part 10, displays the 2nd remaining time which is the remaining time of a 2nd waiting time, and progresses to step S17.

  In step S <b> 17, the control unit 9 determines whether the timing of the second standby time by the timing unit 92 has been completed. If it is determined that the timing of the second waiting time has been completed, an affirmative determination is made and the process proceeds to step S18. If it is determined that the timing of the second waiting time has not been completed, a negative determination is made and the process returns to step S16. In step S <b> 18, the output restriction unit 93 executes a second output restriction that controls the engine 1 to rotate at the idle speed.

According to said 2nd Embodiment, in addition to the effect by 1st Embodiment, the following effect is obtained.
In the abnormality notification device 70 of the second embodiment, the control unit 9 determines that the urea water stored in the urea water tank 6 is less than the first predetermined amount based on the information from the urea water sensor 8, and 2 When it is not less than the predetermined amount, it is determined that the first abnormality has occurred in the exhaust gas purifying device 50. On the other hand, when the urea water stored in the urea water tank 6 falls below the second predetermined amount, the control unit 9 determines that the second abnormality has occurred in the exhaust gas purification device 50. In other words, since both the first abnormality and the second abnormality are determined based on the amount of urea water, the output of the engine 1 can be limited accurately corresponding to the remaining amount of urea water.

(Modification 1 of the first embodiment)
In the first embodiment, when the detection unit 91 detects an abnormality in the exhaust gas purification device 50, the first remaining time is displayed after the first remaining time is displayed to the notification unit 10. Instead, the second remaining time is displayed. However, the first remaining time and the second remaining time may be displayed together. In this case, information related to the contents of the first output restriction may be reported in combination with the information on the first remaining time, and information related to the contents of the second output restriction may be displayed in combination with the information on the second remaining time. preferable. FIG. 6 shows an example of such display. According to the example of the display shown in FIG. 6, the engine output limit (first output limit) is started after 15 minutes in accordance with the abnormality detection of the exhaust gas purifying device, and the engine speed is changed to the idle speed after 10 minutes. This means that notification that "output restriction (second output restriction) is started" is made. By displaying in this way, the operator can cope with the abnormality of the exhaust gas purification device 50 without feeling uneasy.

(Modification 1 of 2nd Embodiment)
In the abnormality notification device 70 according to the second embodiment, the control unit 9 determines that the amount of the urea water is the first based on the information about the urea water stored in the urea water tank 6 transmitted from the urea water sensor 8. A first abnormality in the exhaust gas purification device 50 is detected when the amount falls below the predetermined amount, and a second abnormality is detected when the amount of urea water falls below the second predetermined amount. However, when the remaining amount of urea water reaches a predetermined amount and the first abnormality is detected and the first output restriction is being executed, the second abnormality is detected by a factor other than the amount of urea water, and the second abnormality is based on this. Output restriction may be executed.

(Modification 1 common to the first and second embodiments)
The notification of the remaining time information and the information regarding the content of the output restriction may be displayed in place of other information that has been notified to the notification unit 10 before the abnormality is detected. FIG. 7 shows an example of such display. FIG. 7 shows how the display of the notification unit 10 is switched and displayed when an abnormality is detected. FIG. 7A shows the state of the notification unit 10 immediately before determining the abnormality of the exhaust gas purification device 50. The current time is displayed at the top of the display. FIG. 7B shows the state of the notification unit 10 when the abnormality of the exhaust gas purification device 50 is determined. It can be seen that information on the contents of the first output restriction and information on the first remaining time are displayed instead of the current time at the position where the current time is displayed in FIG. By displaying in this way, it is possible to display information on the remaining time and information on the content of output restriction without increasing the display area of the notification unit 10.

(Modification 2 common to the first and second embodiments)
In each of the above-described embodiments and modifications, a case has been described in which the notification unit 10 is notified by characters or symbols. However, in addition to characters and symbols, voice notification may be performed. As a result, the operator can obtain more information when an abnormality occurs in the exhaust gas purification device 50.

(Modification 3 common to the first and second embodiments)
The detection of abnormality in the exhaust gas purification device 50 is not limited to the detection based on the amount of urea water. In the exhaust gas purification device 50 mounted on the work vehicle 100, for example, even if it is determined that an abnormality has occurred in the exhaust gas purification device 50 based on detection of the states described in (1) to (3) below. Good.
(1) Operation failure of urea water injection device including urea water pump 7 (2) NOx concentration contained in exhaust gas downstream from SCR device 4 exceeds specified value (3) Filter eyes in SCR device 4 Clogging (4) Poor contact of exhaust temperature sensor wiring and electrical wiring in SCR device 4

(Modification 2 of the first embodiment)
The present invention is also applicable as an abnormality notification device for a work vehicle equipped with an exhaust gas purification device in which a DPF device is equipped with a diesel oxidation catalyst (DOC) without being equipped with an SCR device. In this case, when the differential pressure between the inlet pressure and the outlet pressure of the filter of the DPF device becomes the first pressure difference, the first waiting time is notified and the first waiting time until the first output restriction is executed is notified. Start timing. When the time measurement of the first standby time is completed, the first output restriction is executed, the second standby time until the start of the second output restriction that restricts at a lower output than the first output restriction is notified, and the second standby time is issued. Start timing. When the counting of the second waiting time is completed, the second output restriction is executed.
(Modification 2 of the second embodiment)
In the second modification of the first embodiment described above, the timing of the second waiting time is started based on the completion of the timing of the first waiting time. When the second pressure difference becomes larger than the pressure difference, the second standby time is notified and the second standby time is started. When the second standby time is measured, the second output restriction is executed. You may make it do.

  The abnormality notification device 70 can be suitably mounted on a work vehicle including a forklift, a wheel loader, a construction machine, and the like. Therefore, the present invention includes a work vehicle including a forklift and a wheel loader including a diesel engine, an exhaust gas purification device that purifies exhaust gas of the diesel engine, and the various types of abnormality notification devices described above. Furthermore, a forklift including a diesel engine, an exhaust gas purification device having at least a urea SCR device for purifying exhaust gas of the diesel engine, and the above-described various types of abnormality notification devices is also included in the present invention.

  The present invention is not limited to the embodiment described above. Specific constituent materials, parts, and the like may be changed without departing from the scope of the present invention. In addition, if the constituent elements of the present invention are included, a known technique can be added or replaced with a known technique.

DESCRIPTION OF SYMBOLS 1 Engine 2 Oxidation catalyst 3 Diesel particulate filter (DPF) device 4 Urea SCR device 5 Oxidation catalyst 6 Urea water tank 7 Urea water pump 8 Urea water sensor 9 Control unit 10 Notification unit 11 Operation unit 50 Exhaust gas purification device 70 Abnormality notification Device 91 Detection unit 92 Timing unit 93 Output limiting unit 100 Work vehicle

Claims (8)

A detection unit for detecting an abnormality of the exhaust gas purification device;
A timing unit for measuring the first waiting time and the second waiting time;
Based on completion of timing of the first waiting time by the timing unit, a first output limitation is performed to limit the output of the engine to a first limit value, and based on completion of timing of the second waiting time of the timing unit An output limiter that executes a second output limit that limits the engine output to a second limit value that is less than the first limit value;
Notification of the first remaining time that is the remaining time of the first waiting time is started based on the detection of the abnormality by the detection unit, and notification of the second remaining time that is the remaining time of the second waiting time, An abnormality notification device comprising: a notification unit that starts based on completion of timing of the first waiting time. The abnormality notification device according to claim 1,
The detection unit detects a second abnormality in addition to the first abnormality which is the abnormality,
The notification unit
Informing the first remaining time based on the first abnormality,
An abnormality notification device that notifies the second remaining time based on the second abnormality. In the abnormality alarm device according to claim 1 or 2,
The notification unit is an abnormality notification device that displays information on the first output restriction and / or information on the second output restriction together when notifying the first remaining time and / or the second remaining time. In the abnormality alarm device according to any one of claims 1 to 3,
The notification unit
When the abnormality is not detected, information different from the first remaining time and / or the second remaining time is notified to a predetermined position,
An abnormality notification device that notifies the first remaining time and / or the second remaining time at the predetermined position when the abnormality is detected. The abnormality notification device according to claim 1,
The exhaust gas purification device is a urea water SCR device,
The abnormality is an abnormality notification device corresponding to a case where the detection unit detects that the amount of urea water in the urea water SCR device is equal to or less than a predetermined amount. The abnormality notification device according to claim 2,
The exhaust gas purification device is a urea water SCR device,
The first abnormality corresponds to a case where the detection unit detects that the amount of urea water in the urea water SCR device is a first predetermined amount,
The abnormality notification device corresponds to a case where the second abnormality corresponds to a case where the detection unit detects that the amount of urea water in the urea water SCR device is a second predetermined amount smaller than the first predetermined amount. A diesel engine,
An exhaust gas purification device for purifying exhaust gas of the diesel engine;
A work vehicle comprising the abnormality notification device according to any one of claims 1 to 6. A diesel engine,
An exhaust gas purification device having at least a urea selective catalytic reduction system for purifying exhaust gas of the diesel engine;
A forklift comprising the abnormality notification device according to claim 5.

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