JP7563438B2 - CONSTRUCTION MACHINE CONTROL DEVICE AND CONSTRUCTION MACHINE EQUIPPED WITH SAME - Google Patents

Description

This disclosure relates to a control device used in a construction machine equipped with an exhaust gas purification device.

Generally, construction machines such as cranes are equipped with an engine, and the output of the engine drives the elements to be driven in the construction machine. The construction machine is equipped with an exhaust gas purification device for purifying the exhaust gas discharged from the engine. For example, an exhaust gas purification device is known that includes a reduction device that uses urea water as a reducing agent to carry out a selective catalytic reduction (SCR) reaction of nitrogen oxides in the exhaust gas, and an injector for supplying the urea water. In addition to the reduction device, an exhaust gas purification device that includes a device using a DPF (Diesel Particle Filter) or a device using a DOC (Diesel Oxidation Catalyst) is also known. The DPF is a filter that collects fine particles including harmful substances in the exhaust gas of the engine. The DOC is an oxidation catalyst that oxidizes and removes unburned gas in the exhaust gas.

When the engine is running, the temperature of the exhaust gas becomes relatively high, so the injector is cooled by the cooling water circulating through the cooling pipes. However, when the engine is stopped, the operation of the cooling pump that circulates the cooling water is also stopped, so the cooling effect of the cooling water is not obtained. Therefore, if the engine is stopped by turning the ignition key off or the like while the temperature of the exhaust gas is high, the temperature of the injector increases due to the residual exhaust gas in the exhaust pipe, causing the urea water to deteriorate inside the injector. Patent Document 1 discloses a technology for solving such a problem. In this patent document 1, a cooling time calculation unit calculates a cooling time for the temperature of the exhaust gas discharged from the engine to be equal to or lower than a certain value based on the temperature detected by the temperature detection unit, and a notification unit notifies the operator of the need for cooling during the cooling time calculated by the cooling time calculation unit before the engine is stopped.

Patent No. 6365513

Since DOCs purify exhaust gas as it passes through them, the efficiency of exhaust gas purification (purification performance) by the DOC decreases when foreign matter in the exhaust gas accumulates on the DOC. In addition, the particulate matter trapping performance of the DPF, that is, the efficiency of exhaust gas purification, decreases as the amount of particulate matter trapped by the DPF increases. Therefore, when an exhaust gas purification device includes a device using a DOC or DPF, a regeneration process is performed periodically. In the regeneration process, the temperature of the exhaust gas is increased to combust the foreign matter accumulated on the DOC or the particulate matter trapped by the DPF. This restores the efficiency of exhaust gas purification by the DOC or DPF. In other words, the DOC or DPF is regenerated.

The temperature of the exhaust gas differs greatly when the regeneration process is being performed as described above and when it is not being performed. Specifically, the temperature of the exhaust gas in normal operating conditions when the regeneration process is not being performed is, for example, about 200 to 300°C, whereas the temperature of the exhaust gas when the regeneration process is being performed rises to, for example, about 600°C. Then, when the regeneration process is completed, the temperature of the exhaust gas drops rapidly from the high temperature state during the regeneration process to the normal operating state. On the other hand, the behavior of the temperature drop of the injector and its associated parts such as connectors is significantly different from the behavior of the temperature drop of the exhaust gas. However, the technology of Patent Document 1 does not take into account the presence or absence of the regeneration process, nor does it take into account the behavior of the temperature drop of the exhaust gas and the temperature drop of the injector and its associated parts such as connectors.

The present disclosure aims to provide a control device for a construction machine that can appropriately notify the operator that engine shutdown is permitted depending on whether or not a regeneration process is being performed, and a construction machine equipped with the same.

Provided is a control device for a construction machine that includes an engine, an exhaust gas purification device that reduces nitrogen oxides in exhaust gas discharged from the engine using a reducing agent, a supply device that supplies the reducing agent to the exhaust gas purification device, and a cooling device that is driven by the engine and cools the supply device, the control device further includes a first temperature detector that detects the temperature of the exhaust gas, an alarm device that issues a stop permission alarm to notify that the engine is permitted to be stopped, and a controller that controls a regeneration process to restore the purification efficiency of the exhaust gas by the exhaust gas purification device, and the controller is configured to execute a preset temperature detector when the regeneration process is not being performed. The notification device is controlled so that the stop permission notification is issued when the non-regeneration treatment conditions are satisfied, and when the regeneration treatment is being performed, the notification device is controlled so that the regeneration treatment is terminated or interrupted, and the stop permission notification is issued when the preset regeneration treatment conditions are satisfied, the non-regeneration treatment conditions include the temperature of the exhaust gas detected by the first temperature detector being equal to or lower than a non-regeneration treatment reference value that is a preset reference value, and the regeneration treatment conditions include the temperature of the exhaust gas detected by the first temperature detector being equal to or lower than a regeneration treatment reference value that is a preset reference value and is lower than the non-regeneration treatment reference value.

In this control device for construction machinery, the regeneration processing conditions and the non-regeneration processing conditions are set in advance, and when regeneration processing is not being performed, the non-regeneration processing conditions are used to determine whether or not to issue a stop permission notification, and when regeneration processing is being performed, the regeneration processing conditions are used to determine whether or not to issue a stop permission notification. In addition, taking into consideration that the heat capacity of the supply device and its associated parts is greater than the heat capacity of the exhaust gas, the regeneration processing reference value in the regeneration processing conditions is set lower than the non-regeneration processing reference value in the non-regeneration processing conditions. In other words, the regeneration processing reference value in the regeneration processing conditions is a value that indicates a low risk of failure of the supply device even if the engine is stopped and the cooling of the supply device is stopped at that time when the temperature of the exhaust gas detected by the first temperature detector is equal to or lower than the regeneration processing reference value. Therefore, this control device can appropriately issue a notification (stop permission notification) to inform the operator that the engine is allowed to stop depending on whether or not regeneration processing is being performed. As a result, regardless of whether or not regeneration processing is being performed, the engine is stopped with the supply device properly cooled, thereby reducing the risk of the supply device breaking down.

The standard value for regeneration treatment is set in advance through simulations, experiments, etc., taking into consideration the temperature of the exhaust gas when regeneration treatment is being performed, the behavior of the temperature drop of the exhaust gas after regeneration treatment is completed, the behavior of the temperature drop of the supply device and its associated parts after regeneration treatment is completed, etc. Similarly, the standard value for non-regeneration treatment is set in advance through simulations, experiments, etc., taking into consideration the temperature of the exhaust gas when regeneration treatment is not being performed, and the temperature of the supply device and its associated parts, etc.

The controller preferably determines whether the regeneration process conditions are satisfied after the regeneration process is completed or interrupted and a preset first waiting time has elapsed. In this configuration, the determination of whether the regeneration process conditions are satisfied is made after the first waiting time has elapsed, so that a time grace period is given for the temperature of the supply device, which has a large heat capacity, and its associated parts to actually drop to a certain degree before the determination is made. This prevents the determination from being made at a stage where the temperature of the supply device and its associated parts greatly exceeds the regeneration process reference value, thereby reducing the load of calculation processing by the controller.

The controller preferably controls the notification device so that, after the regeneration process is completed or interrupted and a preset first waiting time has elapsed, the controller determines whether the regeneration process conditions are satisfied, and if the regeneration process conditions are not satisfied, the notification device controls the notification device so that the stop permission notification is issued when the non-regeneration process conditions are satisfied after a preset second waiting time has elapsed. When the first waiting time has elapsed and then the second waiting time has elapsed, it is assumed that the temperature of the supply device and its associated parts has reached a temperature at which the risk of failure of the supply device is reduced, even if the exhaust gas temperature still exceeds the regeneration process reference value. Therefore, in this configuration, even if the regeneration process conditions are not satisfied after the regeneration process is completed or interrupted and the first waiting time has elapsed, if the non-regeneration process conditions are satisfied after the second waiting time has elapsed, the stop permission notification is issued. That is, in this case, the non-regeneration process conditions, which have relatively looser criteria than the regeneration process conditions, are used for the judgment, so that the risk of failure of the supply device can be reduced while the stop permission notification can be issued to the operator as soon as possible.

The non-regeneration treatment conditions preferably include the temperature of the exhaust gas detected by the first temperature detector being equal to or lower than the non-regeneration treatment reference value, and the state in which the temperature of the exhaust gas is equal to or lower than the non-regeneration treatment reference value continuing for a predetermined period of time or more. In this configuration, the non-regeneration treatment conditions also include the state in which the temperature of the exhaust gas is equal to or lower than the non-regeneration treatment reference value continuing for a predetermined period of time or more, so that it is possible to eliminate cases in which the temperature of the exhaust gas temporarily falls below the non-regeneration treatment reference value and then exceeds the non-regeneration treatment reference value again. This can improve the accuracy of judgments using the non-regeneration treatment conditions.

The exhaust gas purification device includes a first processing section including a purification element having a characteristic that the purification efficiency is restored in the regeneration process, and a second processing section arranged downstream of the first processing section in the flow of the exhaust gas for performing a reduction reaction using the reducing agent, and the supply device is preferably arranged between the first processing section and the second processing section, and the first temperature detector is arranged between the first processing section and the supply device. In this configuration, since the first temperature detector is arranged between the first processing section and the supply device, it is possible to detect the temperature of the exhaust gas after passing through the first processing section (for example, immediately after passing through the first processing section) and before passing through the supply device or its vicinity. The temperature of the exhaust gas detected at such a position is upstream of the flow of the exhaust gas from the supply device and relatively close to the supply device, and is therefore preferable in terms of evaluating the risk of failure of the supply device compared to the temperature of the exhaust gas detected at other positions. Therefore, in this configuration, the accuracy of the determination of whether or not to perform a stop permission notification can be improved.

The control device of the construction machine further includes a second temperature detector that detects the temperature of the exhaust gas, the second temperature detector being disposed between the supply device and the second processing device, and the controller may control the notification device so that, when the first temperature detector is faulty, the stop permission notification is issued when the temperature of the exhaust gas detected by the second temperature detector is equal to or lower than a second regeneration processing reference value that is a preset reference value and is lower than the regeneration processing reference value. In this configuration, even if the first temperature detector is faulty, it is possible to determine whether or not to issue a stop permission notification using the second temperature detector disposed downstream of the first temperature detector in the exhaust gas flow, specifically between the supply device and the second processing device, and the second regeneration processing reference value that is lower than the regeneration processing reference value.

It is preferable that the controller controls the notification device so that, if the first temperature detector and the second temperature detector are faulty, the stop permission notification is made after a preset third waiting time has elapsed. In this configuration, if both the first temperature detector and the second temperature detector are faulty, the stop permission notification is made after the third waiting time has elapsed. This third waiting time is, for example, set in advance to estimate that the temperature of the supply device and its associated parts has reached a temperature at which the risk of failure of the supply device is reduced. Therefore, in this configuration, even if both the first temperature detector and the second temperature detector are faulty, the stop permission notification can be made after the third waiting time has elapsed.

The provided construction machine is equipped with the control device described above, and can appropriately issue a notification to inform the operator that it is permissible to stop the engine depending on whether or not a regeneration process is being performed.

The present disclosure provides a control device for a construction machine that can appropriately notify the operator that engine shutdown is permitted depending on whether or not regeneration processing is being performed, and a construction machine equipped with the same.

1 is a side view showing a construction machine equipped with a control device according to an embodiment of the present disclosure. 2 is a block diagram showing a functional configuration of the construction machine. FIG. 2 is a block diagram showing an exhaust gas purification device of the construction machine and related configurations. FIG. 4 is a flowchart showing an example of a calculation process performed by a controller of the control device for the construction machine. 5 is a continuation of the flowchart in FIG. 4 .

A control device according to an embodiment of the present disclosure and a construction machine equipped with the same will be described with reference to the drawings. The construction machine according to this embodiment is equipped with an exhaust gas purification device that reduces nitrogen oxides in the exhaust gas discharged from the engine using a reducing agent.

Figure 1 shows a construction machine X1 equipped with a control device according to this embodiment. This construction machine X1 is a crawler crane, but the construction machine to which the control device according to the present disclosure is applied is not limited to crawler cranes, and can be widely applied to other construction machines equipped with exhaust gas purification devices. The other construction machine may be, for example, a wheel crane, a hydraulic excavator, or a bulldozer.

The construction machine X1 comprises a lower travelling body 1, an upper revolving body 2 including a revolving frame 2a supported on the lower travelling body 1 so as to be rotatable and a cab 2b arranged on the revolving frame 2a, and a working device mounted on the revolving frame 2a for performing various operations. The working device comprises a hoisting member 3 capable of performing a hoisting operation on the hoisting frame 2a, a hoisting winch 5 for raising and lowering the hoisting member 3 by winding and unwinding the hoisting rope 4, a main hoisting hook 6 on which a load is hung, a main hoisting winch 8 for hoisting and lowering the main hoisting hook 6 and the load by winding and unwinding the main hoisting rope 7, and an auxiliary hoisting winch 9 for hoisting and lowering the auxiliary hoisting hook (not shown) and the load hung thereon by winding and unwinding the auxiliary hoisting rope (not shown). In this embodiment, the hoisting member 3 is constituted by a boom, but may further comprise a jib (not shown) attached to the tip of the boom.

Figure 2 is a block diagram showing the functional configuration of the construction machine X1. Figure 3 is a diagram showing the exhaust gas purification device of the construction machine X1 and the related configuration.

This construction machine X1 is equipped with an engine 150, an exhaust gas purification device 110 that reduces nitrogen oxides in exhaust gas discharged from the engine 150 using a reducing agent, an injector 120 (an example of a supply device) that supplies the reducing agent to the exhaust gas purification device 110, and a cooling device that is driven by the engine 150 and cools the injector 120. The cooling device includes a cooling pump 151 and cooling piping 170. This construction machine X1 is equipped with a control device that appropriately issues a stop permission notification to inform the operator that the engine 150 is allowed to stop, depending on whether or not regeneration processing is being performed.

The control device includes a first temperature sensor 131 and a second temperature sensor 132 that detect the temperature of the exhaust gas, an alarm device 280 that issues a stop permission alarm, and a controller 250. The controller 250 controls a regeneration process that restores the exhaust gas purification efficiency (exhaust gas purification performance of the exhaust gas purification device 110) of the exhaust gas purification device 110. The regeneration process is performed, for example, by heating a purification element in the exhaust gas purification device 110, which will be described later. The heating of the purification element in the regeneration process may be performed, for example, by increasing the temperature of the exhaust gas. Also, in the regeneration process, the purification element may be directly heated.

The controller 250 includes a computer including, for example, an arithmetic processing device and a memory. The controller 250 includes a machine control unit 251, a determination unit 252, a notification control unit 253, a purification device control unit 254, and an engine control unit 255. Each of the machine control unit 251, the determination unit 252, the notification control unit 253, the purification device control unit 254, and the engine control unit 255 is realized by executing a control program stored in the memory.

The controller 250 controls the notification device 280 so that when the regeneration process is not being performed, a stop permission notification is issued when a preset non-regeneration process condition is satisfied, and when the regeneration process is being performed, the controller 250 controls the notification device 280 so that when the regeneration process is terminated or interrupted and a stop permission notification is issued when a preset regeneration process condition is satisfied. The non-regeneration process condition includes that the first temperature T1, which is the temperature of the exhaust gas detected by the first temperature sensor 131, is equal to or lower than a non-regeneration process reference value, which is a preset reference value. The regeneration process condition includes that the first temperature T1 is equal to or lower than a regeneration process reference value, which is a preset reference value and is lower than the non-regeneration process reference value. The regeneration process reference value is the first reference value in step S18 of FIG. 4 described later, and the non-regeneration process reference value is the fifth reference value in step S35 of FIG. 5 described later. The regeneration process reference value (first reference value) may be set to, for example, 210°C, and the non-regeneration process reference value (fifth reference value) may be set to, for example, 300°C.

In the control device of the construction machine X1, the regeneration processing conditions and the non-regeneration processing conditions are each set in advance, and when the regeneration processing is not being performed, the non-regeneration processing conditions are used to determine whether or not to perform a stop permission notification, and when the regeneration processing is being performed, the regeneration processing conditions are used to determine whether or not to perform a stop permission notification. In addition, taking into consideration that the heat capacity of the injector 120 and its associated parts such as connectors is greater than the heat capacity of the exhaust gas, the regeneration processing reference value (first reference value) in the regeneration processing conditions is set lower than the non-regeneration processing reference value (fifth reference value) in the non-regeneration processing conditions. In other words, the regeneration processing reference value in the regeneration processing conditions is a value that indicates that the risk of failure of the injector 120 is low even if the engine 150 is stopped at that time and the cooling of the injector 120 is stopped, when the temperature of the exhaust gas detected by the first temperature sensor 131 is equal to or lower than the regeneration processing reference value. Therefore, this control device can appropriately perform a stop permission notification to inform the operator that the engine 150 is allowed to stop, depending on whether or not the regeneration processing is being performed. This allows the engine 150 to be stopped with the injector 120 properly cooled, regardless of whether regeneration processing is performed, reducing the risk of the injector 120 failing.

The construction machine X1 will be described in more detail below.

The construction machine X1 further includes a hydraulic pump 153, a plurality of lever operators 210, an accelerator operator 220, a lever operation amount detector 230, an accelerator operation amount detector 240, a control valve 260, and a plurality of actuators 270.

The engine 150 is, for example, a diesel engine, and drives the cooling pump 151 and the hydraulic pump 153.

The cooling pump 151 is driven by the engine 150 to circulate cooling water through the cooling pipes 170. The hydraulic pump 153 is driven by the engine 150 to discharge hydraulic oil. The hydraulic oil discharged from the hydraulic pump 153 is supplied to at least one of the multiple actuators 270 via the control valve 260.

The exhaust gas purification device 110 includes a first processing unit 101 and a second processing unit 102. Each of the first processing unit 101 and the second processing unit 102 performs a process to purify exhaust gas. As shown in FIG. 3, the construction machine X1 includes an upstream exhaust gas pipe 180, an intermediate exhaust gas pipe 181, and a downstream exhaust gas pipe 182. The upstream exhaust gas pipe 180 connects the engine 150 and the first processing unit 101. The intermediate exhaust gas pipe 181 connects the first processing unit 101 and the second processing unit 102. The downstream exhaust gas pipe 182 is connected to the second processing unit 102, and exhaust gas purified in the second processing unit 102 is discharged. The exhaust gas purified by the exhaust gas purification device 110 is discharged into the atmosphere through the downstream exhaust gas pipe 182.

The first processing unit 101 is equipped with a first processing unit body including a purification element that purifies the exhaust gas of the engine 150 and has the characteristic of recovering purification efficiency by heating, a housing that accommodates the purification element, and an introduction pipe provided in the first processing unit body to introduce exhaust gas into the first processing unit body. In this embodiment, the purification element has an oxidation catalyst (Diesel Oxidation Catalyst: hereinafter referred to as DOC) for oxidizing and removing unburned gas in the exhaust gas.

Since the DOC purifies the exhaust gas while it passes through the DOC, if foreign matter in the exhaust gas accumulates in the DOC, the efficiency of purifying the exhaust gas by the DOC decreases. In order to suppress the decrease in the efficiency of purifying the exhaust gas by the first processing unit 101, when the amount of foreign matter accumulated in the first processing unit 101 becomes equal to or greater than a predetermined amount, the first processing unit 101 is heated to burn the foreign matter. For example, the first processing unit 101 can be heated by injecting fuel into the exhaust gas to increase the temperature of the exhaust gas. By burning the foreign matter accumulated in the DOC, the efficiency of purifying the exhaust gas by the DOC is restored and the DOC is regenerated. The method of heating the first processing unit 101 may be, for example, increasing the number of revolutions of the engine 150 to increase the temperature of the exhaust gas, operating a load valve (relief valve) not shown, or adding something that promotes the combustion of the foreign matter.

The load valve performs a load operation for regenerating the DOC (or the DPF described later), specifically, an operation of increasing the load on the engine 150 by increasing the discharge pressure of the hydraulic pump 153 and increasing the driving load of the hydraulic pump 153, thereby increasing the temperature of the exhaust gas. This load valve constitutes a load section together with a load switching valve (not shown) attached to the load valve. The load valve is a pilot-operated pressure control valve provided in the pump line connecting the hydraulic pump 153 and the control valve 260. In other words, the load valve has a pilot port and opens and closes so as to keep the primary pressure of the load valve at or above a set pressure corresponding to the pilot pressure input to the pilot port. The load switching valve is an electromagnetic switching valve having a solenoid, and when the solenoid is not excited, it is kept in an open position and the pilot port of the load valve is connected to the tank, thereby keeping the load valve in an off state (unloaded state). On the other hand, when the solenoid is excited by an excitation current (load command signal) input from the controller 250, it cuts off the connection between the pilot port and the tank and switches the load valve to an on state (a state in which the discharge pressure of the hydraulic pump 153 is increased and a load is applied to the engine 150).

In addition, the first processing unit 101 may have a filter (Diesel Particulate Filter: hereinafter referred to as DPF) for capturing particulate matter in exhaust gas instead of or in addition to the DOC. The particulate matter capturing performance of the DPF, that is, the exhaust gas purification efficiency, decreases as the amount of particulate matter captured by the DPF increases. On the other hand, the exhaust gas purification efficiency of the DPF is restored by heating the DPF and burning the particulate matter captured by the DPF, and the DPF is regenerated.

The second processing unit 102 is equipped with a reduction device for performing a selective catalytic reduction (SCR) reaction of nitrogen oxides in the exhaust gas.

The injector 120 supplies a liquid reducing agent (e.g., urea water) to the exhaust gas purification device 110. As shown in FIG. 3, the construction machine X1 further includes a reducing agent tank 121 that stores the liquid reducing agent, a reducing agent supply pipe 122 that connects the reducing agent tank 121 and the injector 120, and a reducing agent pump (not shown). The injector 120 injects the reducing agent supplied from the reducing agent tank 121 through the reducing agent pump into the exhaust gas pipe. In this embodiment, the injector 120 is attached to the intermediate exhaust gas pipe 181 and supplies the reducing agent to the exhaust gas flowing through the intermediate exhaust gas pipe 181 toward the second treatment device 102. The liquid reducing agent is injected from the injector 120 into the exhaust gas, thereby promoting the SCR reaction in the reduction device of the second treatment device 102.

The first temperature sensor 131 and the second temperature sensor 132 are each attached to the exhaust gas purification device 110, detect the temperature of the exhaust gas flowing through the exhaust gas purification device 110, and input the detection result to the controller 250. The first temperature sensor 131 is an example of a first temperature detector, and the second temperature sensor 132 is an example of a second temperature detector.

The first temperature sensor 131 is provided to detect the temperature of the exhaust gas during the regeneration process of the DOC. That is, the first temperature sensor 131 has the role of detecting the temperature of the exhaust gas during the regeneration process of the DOC, and the role of detecting the temperature of the exhaust gas to determine whether or not each of the regeneration process conditions and the non-regeneration process conditions is satisfied.

The first temperature sensor 131 is preferably disposed, for example, between the first processing unit 101 and the injector 120. The first temperature sensor 131 is attached to the intermediate exhaust gas pipe 181 so as to detect the temperature of the exhaust gas that has been purified in the first processing unit 101 and discharged from the first processing unit 101 to the intermediate exhaust gas pipe 181. In the specific example shown in FIG. 3, the first temperature sensor 131 is attached to the connection portion of the intermediate exhaust gas pipe 181 to the first processing unit 101 or its vicinity, i.e., the upstream end of the intermediate exhaust gas pipe 181 or its vicinity, and detects the temperature of the exhaust gas immediately after it is discharged from the first processing unit 101 to the intermediate exhaust gas pipe 181. However, the attachment position of the first temperature sensor 131 is not limited to the specific example shown in FIG. 3, and may be attached to the intermediate exhaust gas pipe 181 at a position closer to the injector 120 than the upstream end, for example.

The second temperature sensor 132 detects the temperature of the exhaust gas in the second processing section 102 or the temperature of the exhaust gas flowing into the second processing section 102. The second temperature sensor 132 may be disposed, for example, between the injector 120 and the second processing section 102. In the specific example shown in FIG. 3, the second temperature sensor 132 is attached to the connection portion of the intermediate exhaust gas pipe 181 to the second processing section 102 or in its vicinity, i.e., the downstream end of the intermediate exhaust gas pipe 181 or in its vicinity, and detects the temperature of the exhaust gas immediately before it flows into the second processing section 102. However, the attachment position of the second temperature sensor 132 is not limited to the specific example shown in FIG. 3, and may be attached to the intermediate exhaust gas pipe 181 at a position closer to the injector 120 than the downstream end, for example.

Each of the multiple lever operators 210 receives an operator's operation to operate the actuator 270. The multiple lever operators 210 may include, for example, a hoisting member operator for raising and lowering the hoisting member 3, a lifting operator for raising and lowering the main hoisting hook 6, and a rotation operator for rotating the upper rotating body 2.

The accelerator operator 220 may be, for example, an accelerator dial or an accelerator pedal, and receives operator input to adjust the engine 150 speed.

The lever operation amount detector 230 is composed of, for example, a potentiometer, and detects the tilt angle of each of the multiple lever operators 210 as the operation amount for that lever operator 210. The lever operation amount detector 230 inputs the detection result to the controller 250.

The accelerator operation amount detector 240 is composed of, for example, a potentiometer, and detects the operation angle of the accelerator operator 220 as the operation amount for the accelerator operator 220. The accelerator operation amount detector 240 inputs the detection result to the controller 250.

Under the control of the controller 250, the control valve 260 distributes the hydraulic oil discharged from the hydraulic pump 153 to each of the multiple actuators 270.

The actuators 270 may include, for example, a hydraulic motor driven by hydraulic oil supplied via the control valve 260, and a hydraulic cylinder. Specifically, the actuators 270 include, for example, a hydraulic motor that drives the hoisting winch 5 that raises and lowers the hoisting member 3, a hydraulic motor that drives the main hoisting winch 8 that raises and lowers the main hoisting hook 6 in the vertical direction, and a hydraulic motor that rotates the upper rotating body 2.

The machine control unit 251 controls the operation of the construction machine X1 based on the detection results input from detectors such as the first temperature sensor 131, the second temperature sensor 132, the lever operation amount detector 230, and the accelerator operation amount detector 240.

The determination unit 252 determines whether the non-regeneration processing conditions are met, whether the regeneration processing conditions are met, etc. Details of the determination unit 252 will be described later.

The notification control unit 253 controls the notification device 280. The notification device 280 includes a monitor 281 and a cooling lamp 282. The monitor 281, for example, displays a cooling display to inform the operator that the injector 120, etc., is being cooled based on a command from the notification control unit 253. The cooling lamp 282 is a lamp to inform the operator that the injector 120, etc., is being cooled. The notification device 280 may further include, for example, a buzzer.

The purification device control unit 254 controls the injector 120 so that a required amount of reducing agent is injected, for example, according to the temperature of the exhaust gas detected by the first temperature sensor 131. The purification device control unit 254 may control the amount of reducing agent injected from the injector 120, for example, by controlling the opening degree of the injection valve in the injector 120.

The engine control unit 255 controls the engine 150. The engine control unit 255 controls the rotation speed of the engine 150 according to commands from the controller 250. The operator issues an engine on operation to start the engine 150 or an engine off operation to stop the engine 150 to an engine operating device (not shown), such as an ignition key. The engine control unit 255 starts the engine based on the engine on operation and stops the engine based on the engine off operation.

The cooling pump 151 is driven while the engine 150 is running, and the cooling pump 151 stops when the engine 150 stops. Therefore, while the engine 150 is running, the cooling water circulates through the cooling pipe 170, thereby cooling the engine 150, the injector 120, and the exhaust gas purification device 110. The cooling pipe 170 is a circulation path that circulates the cooling water, connected between the engine 150 and the injector 120. The cooling pipe 170 includes a radiator that cools the cooling water, and supplies the cooling water cooled by the radiator to the injector 120 to cool the injector 120.

Figure 4 is a flowchart showing an example of the calculation process performed by the controller 250 of the control device of the construction machine X1, and Figure 5 is a continuation of the flowchart in Figure 4. Below, the control by the controller 250 will be explained with reference to Figures 4 and 5.

In step S11, the determination unit 252 of the controller 250 determines whether or not a regeneration process is being performed to restore the purification efficiency of the DOC (or DPF). The determination unit 252 can determine whether or not a regeneration process is being performed based on, for example, a regeneration signal (CAN) output by the engine control unit 255. The regeneration signal is a signal output by the engine control unit 255 when a regeneration process is being performed or when a regeneration process is not being performed.

If playback processing is being performed, the controller 250 performs the processing from step S12 onward, and if playback processing is not being performed, the controller 250 performs the processing from step S31 onward shown in FIG. 5.

When the regeneration process is being performed (YES in step S11), the notification control unit 253 of the controller 250 controls the notification device 280 so that the cooling lamp 282 lights up or flashes (step S12). This allows the operator to visually check whether the cooling lamp 282 is lit or flashes and recognize that the injector 120 is being cooled by cooling water and that the injector 120 needs to be cooled.

Next, the determination unit 252 of the controller 250 determines whether the playback process has ended or been interrupted (step S13). If the playback process has not ended or been interrupted (NO in step S13), the controller 250 repeats the process of step S13.

When the regeneration process is completed or interrupted (YES in step S13), the notification control unit 253 controls the notification device 280 so that a predetermined cooling display is displayed on the monitor 281 (step S14). This allows the operator to visually check the predetermined cooling display and more reliably recognize through the display on the monitor 281 that, for example, the injector 120 is being cooled by cooling water and that cooling of the injector 120 is required.

Next, the determination unit 252 of the controller 250 determines whether the load valve (not shown) is off or has a malfunction (step S15). The determination unit 252 may determine that the load valve has a malfunction, for example, when the primary pressure of the load valve does not rise to the set pressure, or when a load of the engine 150 equivalent to the set pressure is not obtained.

If the load valve is not off or is not malfunctioning (NO in step S15), the controller 250 repeats the process of step S15.

If the load valve is off or has a malfunction (YES in step S15), the determination unit 252 of the controller 250 determines whether the first waiting time has elapsed (step S16).

The start point of measuring the elapsed time to determine whether the first waiting time has elapsed may be, for example, the point at which it is determined in step S13 that the regeneration process has ended or been interrupted, the point at which a predetermined cooling display is displayed on the monitor 281 in step S14, the point at which it is determined in step S15 that the load valve is off or that the load valve is broken, or any other point that may be a reference point.

If the first waiting time has not elapsed (NO in step S16), the controller 250 repeats the process of step S16.

When the first standby time has elapsed (YES in step S16), the determination unit 252 of the controller 250 determines whether the first temperature sensor 131 is malfunctioning (step S17). The determination unit 252 may determine that the first temperature sensor 131 is malfunctioning, for example, when the value detected by the first temperature sensor 131 does not change despite a change in the load on the engine 150, or may determine that the first temperature sensor 131 is malfunctioning when communication with the first temperature sensor 131 is interrupted for some reason and the temperature cannot be detected.

If the first temperature sensor 131 is not malfunctioning (NO in step S17), the controller 250 performs the process from step S18 onwards, and if the first temperature sensor 131 is malfunctioning (YES in step S17), the controller 250 performs the process from step S21 onwards.

In step S18, the determination unit 252 of the controller 250 determines whether the first temperature T1 detected by the first temperature sensor 131 is equal to or lower than the first reference value (reference value for regeneration process). If the first temperature T1 is equal to or lower than the first reference value (YES in step S18), the notification control unit 253 controls the notification device 280 to delete the cooling display displayed on the monitor 281 (step S26), and controls the notification device 280 to turn off the cooling lamp 282 (step S27).

If the first temperature T1 exceeds the first reference value (reference value for regeneration processing) (NO in step S18), the controller 250 performs processing from step S19 onwards. The processing from step S19 onwards will be described later.

If the first temperature sensor 131 is faulty in step S17 (YES in step S17), the determination unit 252 of the controller 250 determines whether the second temperature sensor 132 is faulty (step S21). The determination unit 252 may determine that the second temperature sensor 132 is faulty, for example, when the value detected by the second temperature sensor 132 does not change despite a change in the load on the engine 150, or may determine that the second temperature sensor 132 is faulty when communication with the second temperature sensor 132 is interrupted for some reason and the temperature cannot be detected.

If the second temperature sensor 132 is faulty (YES in step S21), the determination unit 252 of the controller 250 determines whether the third standby time has elapsed (step S25).

The start point of measuring the elapsed time to determine whether the third waiting time has elapsed in step S25 may be, for example, the point at which it is determined in step S21 that the second temperature sensor 132 is faulty, or may be another point that can serve as a reference.

If the third waiting time has not elapsed (NO in step S25), the controller 250 repeats the process of step S25. If the third waiting time has elapsed (YES in step S25), the notification control unit 253 controls the notification device 280 to delete the cooling display displayed on the monitor 281 (step S26), and controls the notification device 280 to turn off the cooling lamp 282 (step S27).

If the second temperature sensor 132 is not malfunctioning (NO in step S21), the determination unit 252 of the controller 250 determines whether the second temperature T2 detected by the second temperature sensor 132 is equal to or lower than a second reference value (step S22). The second reference value is set to a value lower than the first reference value. Specifically, the second reference value may be set to, for example, 190°C.

If the second temperature T2 is equal to or lower than the second reference value (YES in step S22), the notification control unit 253 controls the notification device 280 to delete the cooling display displayed on the monitor 281 (step S26), and controls the notification device 280 to turn off the cooling lamp 282 (step S27).

If the second temperature T2 exceeds the second reference value (NO in step S22), the notification control unit 253 controls the notification device 280 so that the cooling display displayed on the monitor 281 is deleted (step S23), and the determination unit 252 of the controller 250 determines whether the waiting time has elapsed (step S24). If the waiting time has not elapsed (NO in step S24), the controller 250 repeats the process of step S24. If the waiting time has elapsed (YES in step S24), the controller 250 performs the process of step S40 in FIG. 5.

The process of step S19 will now be described. If the first temperature T1 exceeds the first reference value (reference value for regeneration process) (NO in step S18), the notification control unit 253 of the controller 250 controls the notification device 280 so that the cooling display displayed on the monitor 281 is deleted (step S19), and the determination unit 252 of the controller 250 determines whether the second waiting time has elapsed (step S20).

The start point of measuring the elapsed time to determine whether the second waiting time has elapsed may be, for example, the point at which it is determined in step S18 that the first temperature T1 exceeds the first reference value, or the point at which the cooling display displayed on the monitor 281 is deleted in step S19, or may be a point at which another reference value can be used.

If the second waiting time has not elapsed (NO in step S20), the controller 250 repeats the process of step S20. If the second waiting time has elapsed (YES in step S20), the controller 250 performs the process of step S34 in FIG. 5.

Next, we will explain the flowchart in Figure 5.

If the regeneration process is not being performed in step S11 (NO in step S11), the determination unit 252 of the controller 250 determines whether the first temperature sensor 131 is malfunctioning (step S31). If the first temperature sensor 131 is not malfunctioning (NO in step S31), the controller 250 performs the process of step S32. In step S32, the determination unit 252 of the controller 250 determines whether the state in which the first temperature T1 is equal to or higher than the third reference value is equal to or higher than a predetermined percentage in a predetermined time (step S32). Specifically, in step S32, the determination unit 252 of the controller 250 determines whether the state in which the first temperature T1 is equal to or higher than 310°C is equal to or higher than 60% of the time (6 minutes) in 10 minutes.

If the first temperature T1 is not greater than or equal to the third reference value for a predetermined period of time for a predetermined percentage or more (NO in step S32), the controller 250 repeats the processing from step S11 onward.

If the state in which the first temperature T1 is equal to or higher than the third reference value is equal to or higher than the predetermined percentage for the predetermined time (YES in step S32), the notification control unit 253 controls the notification device 280 to turn on or blink the cooling lamp 282 (step S33).

In step S34, the determination unit 252 of the controller 250 determines whether or not the first temperature sensor 131 is faulty, as described in step S17. If the first temperature sensor 131 is faulty in step S34 (YES in step S34), the controller 250 performs the process of step S40.

If the first temperature sensor 131 is not broken in step S34 (NO in step S34), the determination unit 252 of the controller 250 determines whether the first temperature T1 has remained below the fifth reference value (reference value for non-regeneration processing) for a predetermined time or more (step S35). Specifically, in step S35, the controller 250 determines whether the first temperature T1 has remained below 300°C for 30 seconds or more, for example.

If the first temperature T1 remains below the fifth reference value (reference value for non-regeneration processing) for a predetermined time or longer (YES in step S35), the controller 250 performs processing from step S36 onwards.

If the first temperature T1 does not remain below the fifth reference value (reference value for non-regeneration processing) for a predetermined period of time or more (NO in step S35), the controller 250 performs processing from step S34 onward.

In step S36, the determination unit 252 of the controller 250 determines whether the state in which the first temperature T1 is equal to or higher than the sixth reference value is equal to or higher than a predetermined percentage in a predetermined time. Specifically, in step S36, the determination unit 252 of the controller 250 determines whether the state in which the first temperature T1 is equal to or higher than 310°C is equal to or higher than 60% of the time (6 minutes) in 10 minutes.

If the first temperature T1 is not equal to or greater than the sixth reference value for a predetermined period of time for a predetermined percentage or more (NO in step S36), the notification control unit 253 controls the notification device 280 to turn off the cooling lamp 282 (step S27). If the first temperature T1 is equal to or greater than the sixth reference value for a predetermined period of time for a predetermined percentage or more (YES in step S36), the controller 250 repeats the process from step S34 onwards.

Next, we will explain the process from step S37 onwards.

If the first temperature sensor 131 is faulty (YES in step S31), the controller 250 determines in step S37 whether the second temperature sensor 132 is faulty as described in step S21. If the second temperature sensor 132 is faulty (YES in step S37), the notification control unit 253 controls the notification device 280 so that the cooling lamp 282 lights up or flashes (step S43), and the controller 250 performs the processes from step S44 onward.

If the second temperature sensor 132 is not malfunctioning (NO in step S37), the determination unit 252 of the controller 250 determines whether the state in which the second temperature T2 is equal to or higher than the fourth reference value continues for a predetermined percentage or more for a predetermined time (step S38). Specifically, in step S38, the determination unit 252 of the controller 250 determines whether the state in which the second temperature T2 is equal to or higher than 290°C continues for 60% or more of the time (6 minutes) in 10 minutes, for example.

If the second temperature T2 is not greater than or equal to the fourth reference value for a predetermined period of time for a predetermined percentage or more (NO in step S38), the controller 250 repeats the processing from step S11 onward.

If the second temperature T2 is equal to or higher than the fourth reference value for a predetermined period of time for a predetermined percentage or more (YES in step S38), the notification control unit 253 controls the notification device 280 to turn on or blink the cooling lamp 282 (step S39), and performs the process from step S40 onward.

Next, the process from step S40 onwards will be described. In step S40, the determination unit 252 of the controller 250 determines whether or not the second temperature sensor 132 is malfunctioning, as described in step S21.

If the second temperature sensor 132 is not malfunctioning (NO in step S40), the determination unit 252 of the controller 250 determines whether the second temperature T2 has remained below the seventh reference value for a predetermined period of time or more (step S41). Specifically, in step S41, the determination unit 252 of the controller 250 determines whether the second temperature T2 has remained below 280° C. for 30 seconds or more, for example.

If the second temperature T2 remains below the seventh reference value for a predetermined time or more (YES in step S41), the determination unit 252 of the controller 250 determines whether the second temperature T2 remains above the eighth reference value for a predetermined percentage or more of the predetermined time (step S42). Specifically, in step S42, the determination unit 252 of the controller 250 determines whether the second temperature T2 remains above 290°C for 60% or more of the time (6 minutes) of 10 minutes.

If the second temperature T2 is not greater than or equal to the eighth reference value for a predetermined period of time for a predetermined percentage or more (NO in step S42), the controller 250 repeats the processing from step S11 onward.

If the second temperature T2 is equal to or higher than the eighth reference value for a predetermined period of time for a predetermined percentage or more (YES in step S42), the controller 250 performs the process of step S40.

If the second temperature sensor 132 is faulty in step S40 (YES in step S40), the determination unit 252 of the controller 250 determines whether the load valve is off or faulty (step S44). If the load valve is not off or is not faulty (NO in step S44), the controller 250 repeats the process of step S44.

If the load valve is off or has a malfunction (YES in step S44), the determination unit 252 of the controller 250 determines whether the third waiting time has elapsed (step S45).

The start point of measuring the elapsed time to determine whether the third waiting time has elapsed in step S45 may be, for example, the point at which it is determined in step S37 or step S40 that the second temperature sensor 132 has failed, the point at which the cooling lamp 282 starts to light or blink in step S43, the point at which it is determined in step S44 that the load valve is off or has failed, or any other point that can serve as a criterion. Note that the third waiting time in step S45 may be the same value as the third waiting time in step S25, or may be a different value.

If the third waiting time has not elapsed (NO in step S44), the controller 250 repeats the process of step S44.

If the third waiting time has elapsed (YES in step S44), the notification control unit 253 of the controller 250 controls the notification device 280 to turn off the cooling lamp 282 (step S27).

As described above, in the above embodiment, the controller 250 judges whether the regeneration process conditions are satisfied after the regeneration process is completed or interrupted and a preset first waiting time has elapsed. In this configuration, since the judgment as to whether the regeneration process conditions are satisfied is made after the first waiting time has elapsed, a time grace period is given for the temperature of the supply device 120, which has a large heat capacity, and its associated parts to actually drop to a certain degree before the judgment is made. This prevents the judgment from being made at a stage where the temperature of the supply device 120 and its associated parts greatly exceeds the regeneration process reference value, thereby reducing the load of calculation processing by the controller 250.

In the above embodiment, the controller 250 determines whether the regeneration process conditions are satisfied after the regeneration process is completed or interrupted and a preset first waiting time has elapsed, and if the regeneration process conditions are not satisfied, the controller 250 controls the notification device 280 so that the stop permission notification is made when the non-regeneration process conditions are satisfied after a preset second waiting time has elapsed. When the first waiting time has elapsed and then the second waiting time has elapsed, it is assumed that the temperature of the supply device 120 and its associated parts has reached a temperature at which the risk of failure of the supply device 120 is reduced, even if the exhaust gas temperature still exceeds the regeneration process reference value. Therefore, in this configuration, even if the regeneration process conditions are not satisfied after the regeneration process is completed or interrupted and the first waiting time has elapsed, if the non-regeneration process conditions are satisfied after the second waiting time has elapsed, the stop permission notification is made. In other words, in this case, the non-regeneration processing conditions, which have relatively lenient criteria compared to the regeneration processing conditions, are used for the judgment, so that the risk of failure of the supply device 120 can be reduced while the stop permission notification can be given to the operator as soon as possible.

In the above embodiment, the non-regeneration treatment conditions include the temperature of the exhaust gas detected by the first temperature detector 131 being equal to or lower than the non-regeneration treatment reference value, and the state in which the temperature of the exhaust gas is equal to or lower than the non-regeneration treatment reference value continuing for a predetermined period of time or more. In this configuration, the non-regeneration treatment conditions also include the state in which the temperature of the exhaust gas is equal to or lower than the non-regeneration treatment reference value continuing for a predetermined period of time or more, so that it is possible to eliminate cases in which the temperature of the exhaust gas temporarily falls below the non-regeneration treatment reference value and then exceeds the non-regeneration treatment reference value again. This can improve the accuracy of judgments using the non-regeneration treatment conditions.

In the above embodiment, the exhaust gas purification device 110 includes a first processing section 101 including a purification element having a characteristic that the purification efficiency is restored by increasing the temperature of the exhaust gas in the regeneration process, and a second processing section 102 arranged downstream of the flow of the exhaust gas from the first processing section 101 and for performing a reduction reaction using the reducing agent, and the supply device 120 is arranged between the first processing section 101 and the second processing section 102, and the first temperature detector 131 is arranged between the first processing section 101 and the supply device 120. In this configuration, the first temperature detector 131 is arranged between the first processing section 101 and the supply device 120, so that the temperature of the exhaust gas after passing through the first processing section 101 (for example, immediately after passing through the first processing section 101) and before passing through the supply device 120 or its vicinity can be detected. The exhaust gas temperature detected at such a position is upstream of the supply device 120 in the flow of exhaust gas and relatively close to the supply device 120, and is therefore preferable in terms of evaluating the risk of failure of the supply device 120 compared to exhaust gas temperatures detected at other positions. Therefore, this configuration can improve the accuracy of the determination of whether or not to issue a stop permission notification.

In the above embodiment, the control device of the construction machine further includes a second temperature detector 132 that detects the temperature of the exhaust gas, and the second temperature detector 132 is disposed between the supply device 120 and the second processing unit 102. When the first temperature detector 131 is broken, the controller 250 controls the notification device 280 so that the stop permission notification is issued when the temperature of the exhaust gas detected by the second temperature detector 132 is equal to or lower than a second regeneration processing reference value that is a preset reference value and is lower than the regeneration processing reference value. In this configuration, even if the first temperature detector 131 is broken, it is possible to determine whether or not to issue a stop permission notification using the second temperature detector 132 disposed downstream of the first temperature detector 131 in the exhaust gas flow, specifically between the supply device 120 and the second processing unit 102, and the second regeneration processing reference value that is lower than the regeneration processing reference value.

In the above embodiment, the controller 250 controls the notification device 280 so that, if the first temperature detector 131 and the second temperature detector 132 are broken, the stop permission notification is made after a preset third waiting time has elapsed. In this configuration, if both the first temperature detector 131 and the second temperature detector 132 are broken, the stop permission notification is made after the third waiting time has elapsed. This third waiting time is set in advance, for example, to estimate that the temperature of the supply device 120 and its associated parts has reached a temperature at which the risk of failure of the supply device 120 is reduced. Therefore, in this configuration, even if both the first temperature detector 131 and the second temperature detector 132 are broken, the stop permission notification can be made after the third waiting time has elapsed.

[Modification]
The present disclosure is not limited to the above-described embodiment. The present disclosure includes, for example, the following aspects.

(A) The regeneration treatment conditions may include that the temperature of the exhaust gas detected by the first temperature detector is equal to or lower than the regeneration treatment reference value, and that the state in which the temperature of the exhaust gas is equal to or lower than the regeneration treatment reference value continues for a predetermined period of time or more.

(B) The supply device does not necessarily have to be an injector.

(C) The cooling device does not necessarily have to include a cooling pump 151 and cooling piping 170.

(D) The load valve (relief valve) described in the above embodiment may be omitted.

101: First processing unit 102: Second processing unit 110: Exhaust gas purification device 120: Injector 131: First temperature sensor 132: Second temperature sensor 150: Engine 151: Cooling pump 170: Cooling piping 180: Upstream exhaust gas pipe 181: Intermediate exhaust gas pipe 182: Downstream exhaust gas pipe 250: Controller 280: Notification device 281: Monitor 282: Cooling lamp T1: First temperature T2: Second temperature X1: Construction machine

Claims (8)

A control device for a construction machine including an engine, an exhaust gas purification device that reduces nitrogen oxides in exhaust gas discharged from the engine by using a reducing agent, a supply device that supplies the reducing agent to the exhaust gas purification device, and a cooling device that is driven by the engine and cools the supply device,
A first temperature detector for detecting a temperature of the exhaust gas;
an alert device that provides an alert to notify the driver that the engine is permitted to be stopped;
a controller that controls a regeneration process for recovering the purification efficiency of the exhaust gas by the exhaust gas purification device,
The controller controls the notification device so that the stop permission notification is given when a preset non-regeneration processing condition is satisfied when the regeneration processing is not being performed, and controls the notification device so that the stop permission notification is given when the regeneration processing is terminated or interrupted and a preset regeneration processing condition is satisfied when the regeneration processing is being performed,
The non-regeneration treatment condition includes that the temperature of the exhaust gas detected by the first temperature detector is equal to or lower than a non-regeneration treatment reference value, which is a preset reference value;
A control device for a construction machine, wherein the conditions for regeneration treatment include the temperature of the exhaust gas detected by the first temperature detector being equal to or lower than a predetermined standard value for regeneration treatment, which is lower than the standard value for non-regeneration treatment. The control device for a construction machine according to claim 1,
A control device for a construction machine, wherein the controller determines whether or not the regeneration process conditions are satisfied after the regeneration process has ended or been interrupted and a preset first standby time has elapsed. The control device for a construction machine according to claim 1,
A control device for a construction machine, wherein the controller determines whether the regeneration processing conditions are satisfied after the regeneration processing is completed or interrupted and a predetermined first waiting time has elapsed, and if the regeneration processing conditions are not satisfied, controls the notification device so that the stop permission notification is made when the non-regeneration processing conditions are satisfied after a predetermined second waiting time has elapsed. The control device for a construction machine according to claim 1,
A control device for a construction machine, wherein the non-regeneration treatment conditions include the temperature of the exhaust gas detected by the first temperature detector being below the non-regeneration treatment standard value and the state in which the temperature of the exhaust gas is below the non-regeneration treatment standard value continuing for a predetermined period of time or more. The control device for a construction machine according to claim 1,
The exhaust gas purification device includes a first treatment section including a purification element having a characteristic that the purification efficiency is restored in the regeneration process, and a second treatment section that is disposed downstream of the first treatment section in a flow of the exhaust gas and that performs a reduction reaction using the reducing agent,
The supply device is disposed between the first processing section and the second processing section,
A control device for a construction machine, wherein the first temperature detector is disposed between the first processing unit and the supply device. The control device for a construction machine according to claim 5,
A second temperature detector is further provided for detecting a temperature of the exhaust gas.
the second temperature detector is disposed between the supply device and the second processing section;
The controller controls the alarm device so that, when the first temperature detector fails, the stop tolerance alarm is issued when the temperature of the exhaust gas detected by the second temperature detector is equal to or lower than a second regeneration treatment reference value which is a preset reference value and is lower than the regeneration treatment reference value. The control device for a construction machine according to claim 6,
A control device for a construction machine, wherein the controller controls the alarm device so that the stop permission alarm is issued after a preset third waiting time has elapsed when the first temperature detector and the second temperature detector are faulty. A construction machine equipped with a control device according to any one of claims 1 to 7.