JP2020166745A - Construction machine - Google Patents

Abstract

To provide a construction machine that is able to detect an anomaly during operation of a machine body and specify a factor of the anomaly, regardless of the number of construction machines sold in a market.SOLUTION: A controller 50 stores a normal-time mode 51, which is a simulation model for simulating a normal operation of a construction machine, and also stores information about a factor of an anomaly of a quantity of characteristic. During an operation of the construction machine, pose information acquired by sensors 31-36, 41, 42 or information output from an operation instruction device is input to the normal-time model, thereby calculating a quantity of theoretical characteristic, which is a theoretical value of the quantity of characteristic. Based on a result of a comparison between a quantity of characteristic actually measured, which is a quantity of characteristic detected by the sensor, and the quantity of theoretical characteristic, it is determined whether or not there is an anomaly in the quantity of characteristic actually measured. In a case where it is determined that there is an anomaly in the quantity of characteristic actually measured, an instruction for urging a prescribed operation necessary to specify a factor of the anomaly is output to a notification device 62.SELECTED DRAWING: Figure 6

Description

The present invention relates to construction machinery such as hydraulic excavators.

Construction machines such as hydraulic excavators are used at various construction sites, civil engineering sites, etc., and in order to minimize the interruption of work, we diagnose failures and abnormalities in advance and repair quickly when failures occur. Is required to do. Therefore, the development of a system for determining an abnormality based on the feature amount obtained from an operating construction machine is in progress. For example, Patent Document 1 is a prior art document that discloses a method for determining an abnormality of a shovel.

In Patent Document 1, a plurality of reference waveforms representing a time change of a detected value of a physical quantity of interest obtained from the excavator are prepared during a period in which the excavator is operated and a certain predetermined operation is performed. A plurality of feature quantities are obtained for each of the reference waveforms, and a method of determining whether or not there is an abnormality in the evaluation target excavator of the same type as the excavator based on the reference waveform is described in (a) the evaluation target. A step of driving the excavator, detecting the physical quantity of interest obtained from the evaluation target excavator during a period of performing an operation similar to the default operation, and acquiring an evaluation waveform which is a time change of the detected value, and (b). ) Obtaining the feature quantity of the evaluation waveform, an average vector of a plurality of reference vectors having the feature quantity of each of the plurality of reference waveforms as elements, and an evaluation vector having the feature quantity of the evaluation waveform as an element. Describes a method for determining an abnormality in an excavator, which comprises a step of determining the presence or absence of an abnormality in the excavator to be evaluated based on the result of comparison with.

Japanese Unexamined Patent Publication No. WO2014-119110

In the abnormality determination method described in Patent Document 1, it is necessary to acquire a large number of reference waveforms in advance with a shovel of the same model in order to ensure determination accuracy. However, some hydraulic excavators have a small number of models and specifications on the market, and it is difficult to obtain a large number of reference waveforms from such a small number of hydraulic excavators. Therefore, the abnormality determination method described in Patent Document 1 is not suitable for a small number of hydraulic excavators on the market.

The present invention has been made in view of the above problems, and an object of the present invention is to detect an abnormality during operation of an airframe and identify the cause of the abnormality regardless of the number of units on the market. It is to provide possible construction machinery.

In order to achieve the above object, the present invention comprises a hydraulic pump, a hydraulic actuator driven by the hydraulic pump, a controller having a calculation function, a notification device for outputting the calculation result of the controller, and the hydraulic actuator. In a construction machine provided with information output from an operation instruction device for instructing an operation or attitude information of the construction machine, and a sensor for acquiring a feature amount indicating an operating state of the construction machine, the controller is a device of the construction machine. The normal model, which is a simulation model that simulates the normal operation, and the information of the factors for the abnormality of the feature amount are stored, and the posture information acquired by the sensor or the operation during the operation of the construction machine is stored. By inputting the information output from the indicator into the normal model, the theoretical feature amount which is the theoretical value of the feature amount is calculated, and the actually measured feature amount and the theoretical feature amount which are the feature amounts detected by the sensor. Based on the comparison result with, it is determined whether or not the measured feature amount is abnormal, and when it is determined that the measured feature amount is abnormal, the default operation required to identify the cause of the abnormality. It is assumed that an instruction prompting is output to the notification device.

According to the present invention configured as described above, the measured feature amount is abnormal based on the comparison result between the measured value (measured feature amount) and the theoretical value (theoretical feature amount) of the feature amount indicating the operating state of the construction machine. When it is determined that there is an abnormality in the measured feature amount, an instruction for prompting a default operation necessary for identifying the cause of the abnormality is output to the notification device. This allows the operator or service personnel to identify the abnormality of the construction machine and the cause of the abnormality during the operation of the construction machine.

Further, in the present invention, since the abnormality determination and the factor determination are performed using the normal time model and the abnormal time model constructed according to the model and specifications of the construction machine, the data acquired by other construction machines is not required. This makes it possible to apply the present invention to a small number of construction machines on the market.

According to the construction machine according to the present invention, it is possible to detect an abnormality during operation of the machine and identify the cause of the abnormality regardless of the number of units on the market.

It is a side view of the hydraulic excavator which concerns on embodiment of this invention. It is a schematic block diagram of the hydraulic drive system mounted on the hydraulic excavator shown in FIG. It is a flowchart which showed the work procedure of (step 1) of the work flow which concerns on this invention. It is a flowchart which showed the work procedure of (step 2) of the work flow which concerns on this invention. It is a flowchart which showed the work procedure of (step 3) of the work flow which concerns on this invention. It is a functional block diagram of the controller shown in FIG. It is the figure which superposed the time-series waveform of the measured value (measured feature amount) of an arm speed, and the time-series waveform of the theoretical value (theoretical feature amount at the time of normal) of an arm speed. It is a matrix that correlates the assumed factor of abnormality that the arm speed becomes slower than normal and the tendency of the average flow rate on the bottom side of the arm cylinder acquired when the hydraulic excavator having the assumed factor performs the default operation. .. It is a flowchart which showed the work procedure of the step 1 when the oil leakage on the bottom side of an arm cylinder is assumed as an assumed factor. It is a figure which showed the model at the time of abnormality simulating the oil leakage on the bottom side of an arm cylinder. It is a flowchart which showed the work procedure of the step 1 when the sticking of an arm regeneration valve is a presumed factor. Regarding the average flow rate on the bottom side of the arm cylinder when the default operation 1 is performed for one cycle, the measured features acquired by the hydraulic excavator at the time of abnormality, the theoretical features acquired by the abnormal model, and the theoretical features acquired by the normal model. It is a figure which showed and side by side. Regarding the average flow rate on the bottom side of the arm cylinder when the default operation 2 is performed for one cycle, the measured features acquired by the hydraulic excavator at the time of abnormality, the theoretical features acquired by the abnormal model, and the theoretical features acquired by the normal model. It is a figure which showed and side by side. Regarding the average flow rate on the bottom side of the arm cylinder when the default operations 1 and 2 are performed for one cycle, the average flow rate acquired by the normal hydraulic excavator and the average flow rate acquired by the abnormal hydraulic excavator are superimposed and shown in the figure. is there. It is the figure which showed by rearranging the measured feature amount acquired by the hydraulic excavator at the time of abnormality and the theoretical feature amount acquired by the model at the time of abnormality about the average flow rate of the arm cylinder bottom side flow rate in order of magnitude. A matrix that links the assumed factor of abnormality that the boom lowering speed becomes slower than normal and the tendency of the average flow rate on the rod side of the boom cylinder acquired when the hydraulic excavator with that assumed factor performs the default operation. is there. The hypothetical factor of abnormality that the bottom side pressure of the hydraulic cylinder that drives the front device becomes lower than normal, and the bottom side pressure of each hydraulic cylinder acquired when the hydraulic excavator having the presumed factor performs the default operation. It is a matrix in which trends are associated with each other.

Hereinafter, a hydraulic excavator will be taken as an example of a construction machine according to an embodiment of the present invention, and will be described with reference to the drawings. In each figure, the same members are designated by the same reference numerals, and duplicate description will be omitted as appropriate.

FIG. 1 is a side view of a hydraulic excavator according to an embodiment of the present invention.

As shown in FIG. 1, the hydraulic excavator 100 has a traveling body 3 provided with a pair of left and right traveling devices 1 and 2, a rotating body 4 mounted on the traveling body 3, and one end of which is rotatable to the rotating body 4. It includes a boom 5 pin-coupled to the boom 5, an arm 6 having one end rotatably pin-coupled to the boom 5, and a bucket 7 rotatably pin-coupled to the arm 6 at one end. The boom 5, arm 6, and bucket 7 constitute the front device 101. A driver's cab 8, a machine room 9 for storing an engine and a hydraulic pump, a counterweight 10, and the like are provided on the swivel body 4.

The traveling devices 1 and 2 are driven by the traveling motors 11 and 12, and the swivel body 4 is driven by the swivel motor 13. The boom 5 is driven by the boom cylinders 14 and 15, the arm 6 is driven by the arm cylinder 16, and the bucket 7 is driven by the bucket cylinder 17. The postures of the boom 5, arm 6, and bucket 7 are determined by the amount of movement of the boom cylinders 14, 15, arm cylinder 16, and bucket cylinder 17 in the expansion and contraction direction.

FIG. 2 is a schematic configuration diagram of a hydraulic drive system mounted on the hydraulic excavator 100. In FIG. 2, only the parts related to the driving of the boom cylinders 14 and 15 and the arm cylinder 16 are shown, and the parts related to the driving of the other actuators are omitted.

In FIG. 2, the discharge oil passage 22 of the hydraulic pump 21 is connected to the tank 24 via the main relief valve 23. The boom direction control valve 25 controls the direction and flow rate of the pressure oil supplied from the hydraulic pump 21 to the boom cylinders 14 and 15. The arm direction control valve 26 controls the direction and flow rate of the pressure oil supplied from the hydraulic pump 21 to the arm cylinder 16.

The bottom side of the boom cylinders 14 and 15 and the bottom side of the arm cylinder 16 are connected via an arm reclaimed oil passage 27, and the arm reclaimed oil passage 27 is discharged from the bottom side of the boom cylinders 14 and 15. An arm regeneration valve 28 for controlling the flow rate of hydraulic oil supplied to the bottom side of the arm cylinder 16 among the oil is provided. Although not shown, the bottom side of the boom cylinders 14 and 15 and the rod side are connected to each other via a boom regeneration oil passage, and the boom cylinders 14 and 15 are discharged from the bottom side of the boom regeneration oil passage. A boom regeneration valve for controlling the flow rate of the hydraulic oil supplied to the rod side of the boom cylinders 14 and 15 is provided.

Pressure sensors 31 to 34 for detecting the pilot pressure are provided in the pilot pressure receiving portions of the directional control valves 25 and 26, respectively. Pressure sensors 35 and 36 and flow rate sensors (not shown) are provided in the bottom oil passages of the boom cylinders 14 and 15 and the arm cylinder 16, respectively. Stroke sensors 41 and 42 are provided on the boom cylinders 14 and 15 and the arm cylinder 16, respectively.

The controller 60 performs an abnormality diagnosis of the hydraulic excavator 100 in response to the operation of the mode changeover switch 61. Specifically, the presence or absence of an abnormality is determined based on the detection results of each sensor, and if it is determined that there is an abnormality, the cause is identified and the abnormality information and the factor information are output to the monitor 62.

The work flow related to the present invention will be described by roughly dividing it into three stages (stage 1, stage 2, and stage 3).

FIG. 3 is a flowchart showing the work procedure of step 1. The flow shown in FIG. 3 is performed for each type of abnormality that can occur in the hydraulic excavator 100. Hereinafter, each step will be described in order.

In step SA1, the possible factors of abnormality are listed.

In step SA2, an abnormal time model 200 that simulates the assumed factors listed in step SA1 is created.

In step SA3, a parameter indicating the degree of abnormality is set in the abnormality model 200.

In step SA4, the default operation required to identify the cause of the abnormality is performed in the abnormality model 200.

In step SA5, the feature amount (theoretical feature amount at the time of abnormality) when the default operation is performed by the abnormality model 200 is calculated.

In step SA5, a matrix in which the assumed factor, the default operation, and the theoretical feature amount at the time of abnormality calculated in step SA5 are associated is stored in the storage unit 53 (shown in FIG. 6) of the controller 50 described later.

FIG. 4 is a flowchart showing the work procedure of step 2. Hereinafter, each step will be described in order.

FIG. 4 is a flowchart showing the work procedure of step 2. In stage 2, the presence or absence of an abnormality is determined by acquiring the time-series data of the measured features with the hydraulic excavator 100, which is performing normal work, and comparing it with the time-series data of the theoretical features calculated by the normal model 51. To do. Hereinafter, each step will be described in order.

In step SB1, it is determined whether or not the start of the abnormality diagnosis data acquisition mode is instructed (whether or not the mode changeover switch 61 is ON). If it is determined in step SB1 that the mode changeover switch 61 is ON (YES), the process proceeds to step SB2. If it is determined in step SB1 that the mode changeover switch 61 is OFF (NO), the process returns to step SB1.

In step SB2, the operation information and attitude information of the hydraulic excavator 100 and the measured value (measured feature amount) of the feature amount indicating the operating state of the hydraulic excavator 100 are acquired from the sensors mounted on the actual machine (pressure sensor, stroke sensor, flow rate sensor, etc.). To do.

In step SB3, the operation information or the posture information of the hydraulic excavator 100 is input to the normal model 51, and the theoretical value of the feature amount (theoretical feature amount in the normal state) is calculated.

In step SB4, it is determined whether or not the end of the abnormality diagnosis data acquisition mode is instructed (whether or not the mode changeover switch 61 is OFF). If it is determined in step SB4 that the mode changeover switch 61 is OFF (YES), the process proceeds to step SB5. If it is determined in step SB4 that the mode changeover switch 61 is ON (YES), the process returns to step SB2.

In step SB5, the time-series data of the actually measured features acquired in step SB2 and the time-series data of the theoretical features in the normal state acquired in step SB3 are compared.

In step SB6, it is determined whether or not the deviation rate of the measured feature amount from the theoretical feature amount at the normal time is equal to or more than a predetermined threshold value. The predetermined threshold value here is set to a deviation rate (for example, 5%) to the extent that the operator feels some abnormality during the operation of the hydraulic excavator, but cannot determine which actuator has the abnormality.

If it is determined in step SB6 that the deviation rate is equal to or greater than the threshold value (YES), the default operation required for identifying the cause of the abnormality is extracted from the matrix of the storage unit 53 (step SB7), and the process proceeds to step 3. To do.

If it is determined in step SB6 that the deviation rate is less than the threshold value (NO), it is determined that there is no abnormality (step SB8), and the abnormality diagnosis is terminated.

FIG. 5 is a flowchart showing the work procedure of step 3. In step 3, the cause of the abnormality is identified by comparing the actually measured feature amount acquired by causing the hydraulic excavator 100 to perform a predetermined operation and the theoretical feature amount at the time of abnormality stored in the storage unit 53. Hereinafter, each step will be described in order.

In step SC1, an instruction prompting one of the default operations extracted in step SB7 of step 2 is output to the monitor 62.

In step SC2, it is determined whether or not the operator has performed the default operation. If YES is determined in step SC2, the process proceeds to step SC3. If NO is determined in step SC2, the process returns to step SC2.

In step SC3, it is determined whether or not there is an unexecuted default action among the default actions extracted in step SB7 of step 2. If YES is determined in step SC3, an instruction prompting another default operation (one of unexecuted default operations) is output to the monitor 62 (step SC4), and the process returns to step SC2. If NO is determined in step SC3, the process proceeds to step SC5.

In step SC5, the measured feature amount at the time of the default operation is compared with the theoretical feature amount at the time of abnormality stored in the storage unit 53, and the cause of the abnormality is specified.

In step SC6, the abnormality information and the cause information are output to the monitor 62.

FIG. 6 is a functional block diagram of the controller 50.

In FIG. 6, the controller 50 has a normal model 51, an abnormality determination unit 52, a storage unit 53, and a factor determination unit 54.

The normal model 51 is a simulation model that simulates the normal operation of the hydraulic excavator 100, and is based on the operation information or attitude information of the hydraulic excavator 100 obtained from the sensors 31 to 36, 41, 42 mounted on the actual machine. The theoretical value (theoretical feature amount) of the feature amount indicating the operating state of the above is calculated and output to the abnormality determination unit 52.

The abnormality determination unit 52 compares the theoretical feature amount calculated by the normal model 51 with the feature amount (measured feature amount) of the hydraulic excavator 100 acquired by the sensors 31 to 36, 41, 42 mounted on the actual machine, and obtains the result. Based on this, it is determined whether or not the hydraulic excavator 100 has an abnormality. When the abnormality determination unit 52 determines that the hydraulic excavator 100 has an abnormality, the abnormality determination unit 52 outputs the information to the monitor 62.

The storage unit 53 stores a matrix (described later) in which an abnormality assumption factor and a tendency of the actually measured feature amount acquired when the hydraulic excavator having the assumption factor performs a predetermined operation are associated with each other.

The factor determination unit 54 refers to the matrix stored in the storage unit 53, identifies the cause of the abnormality based on the actually measured feature quantities obtained from the sensors 31 to 36, 41, 42 mounted on the actual machine, and monitors the information 62. Output to. Further, when the operation (default operation) necessary for identifying the cause of the abnormality has not been performed, the factor determination unit 54 outputs an operation instruction of the default operation to the monitor 62.

FIG. 7 shows a time-series waveform of an actually measured value (measured feature amount) of the arm speed acquired when the hydraulic excavator 100 performs an operation to which the regeneration control is applied, and a theoretical value (normal) obtained by the normal model 51. It is the figure which superposed the time series waveform of (theoretical feature amount of time). Here, the regeneration control is a control for accelerating the speed of the arm cylinder 16 by supplying the hydraulic oil discharged from the boom cylinders 14 and 15 to the arm cylinder 16 via the arm regeneration valve 28.

In the example shown in FIG. 7, the measured value of the arm speed (measured feature amount) is smaller than the theoretical value of the arm speed (theoretical feature amount at the normal time). At this time, since it is known that the solenoid valve for switching the spool of the arm regeneration valve 28 is also operating normally, it is considered that the defect of the arm regeneration valve 28 is a cause of the abnormality. However, even if an oil leak occurs in the hose connected to the bottom side of the arm cylinder 16, the speed of the arm 6 slows down, so that the cause of the abnormality cannot be narrowed down to one at this point. Therefore, the default motion that is expected to slow down the arm speed is performed as necessary, and the measured feature quantity obtained at that time is compared with the theoretical feature quantity obtained by performing the default motion on the abnormal model 200. By doing so, the cause of the abnormality is identified.

FIG. 8 corresponds to a hypothetical factor of an abnormality in which the arm speed becomes slower than normal and a tendency of the average flow rate on the bottom side of the arm cylinder 16 acquired when the hydraulic excavator having the presumed factor performs a predetermined operation. It is a attached matrix.

In FIG. 8, the default operation 1 is an operation in which the boom 5 is raised to the maximum and the arm is pulled without operating the boom 5 (operation in which the reproduction control is not applied), and the arm 6 is fully dumped from the full dump state. The operation until the transition to the cloud state is defined as one cycle. Further, the default operation 2 is an operation when the boom raising operation is performed with the boom 5 raised to the maximum and at the same time the arm pulling operation is performed with the full lever (operation in which the reproduction control is applied), and the arm 6 is fully dumped. The operation from the state to the full cloud state is defined as one cycle.

According to the matrix M1 shown in FIG. 8, the average flow rate (measured feature amount) on the bottom side of the arm cylinder 16 when the default operations 1 and 2 are performed, and the default operation 1 and 2 are performed by the model 200 at the time of abnormality. By comparing with the average flow rate on the bottom side of the arm cylinder 16 (theoretical feature amount at the time of abnormality), the cause of the abnormality that the arm speed becomes slower than the normal time is three assumed factors (the bottom side of the arm cylinder 16). It is specified as one of oil leakage, sticking of the arm regenerating valve 28, oil leak on the bottom side of the arm cylinder 16 + sticking of the arm regenerating valve 28).

FIG. 9 is a flowchart showing the work procedure of step 1 when an oil leak on the bottom side of the arm cylinder 16 is used as an assumed factor. Hereinafter, each step will be described in order.

In step SD1, oil leakage on the bottom side of the arm cylinder 16 is assumed as an assumed factor.

In step SD2, an abnormal time model 200 that simulates an oil leak on the bottom side of the arm cylinder 16 is created. FIG. 10 shows an abnormal model 200 that simulates an oil leak on the bottom side of the arm cylinder 16. The abnormal model 200 here is a simulation model assuming that an oil leak occurs in the oil passage 71 connecting the arm direction control valve 36 and the bottom side of the arm cylinder 16, and is an oil passage in the normal model 51. A leaky oil passage 72 for connecting the 71 to the tank 24 is added, a variable throttle valve 73 is installed in the leaky oil passage 72, and the throttle amount (parameter) of the variable throttle valve 73 is adjusted according to the degree of oil leakage. And.

Returning to FIG. 9, in step SD3, the throttle amount (parameter of the model 200 at the time of abnormality) of the variable throttle valve 73 is set in three ways (small degree, medium degree, large degree).

In step SD4, the default operations 1 and 2 are performed in the abnormal time model 200 after setting the parameters.

In step SD5, the bottom-side average flow rate (theoretical feature amount at the time of abnormality) of the arm cylinder 16 in the abnormal time model 200 in which the default operations 1 and 2 are performed is calculated.

In step SD6, the average flow rate on the bottom side of the arm cylinder 16 calculated in step SD5 (theoretical feature amount at the time of abnormality) is stored in association with the assumed factor (oil leakage on the bottom side of the arm cylinder 16) and the default operations 1 and 2. It is stored in the part 53.

FIG. 11 is a flowchart showing the work procedure of step 1 when the sticking of the arm regeneration valve 28 is a presumed factor. Hereinafter, each step will be described in order.

In step SE1, the sticking of the arm regeneration valve 28 is assumed as a assumed factor.

In step SE2, an abnormal time model 200 simulating the sticking of the arm regeneration valve 28 is created. In the abnormal model 200 here, it is assumed that the spool movement amount of the arm regeneration valve 28 is fixed to a predetermined value in the normal model 51.

In step SE3, the spool movement amount of the arm regeneration valve 28 is set in three ways (0%, 30%, and 50% in the normal state).

In step SE4, the default operations 1 and 2 are performed in the abnormal time model 200 after setting the parameters.

In step SE5, the bottom-side average flow rate (theoretical feature amount at the time of abnormality) of the arm cylinder 16 in the abnormal time model 200 in which the default operations 1 and 2 are performed is calculated.

In step SE6, the average flow rate on the bottom side of the arm cylinder 16 calculated in step SD5 (theoretical feature amount at the time of abnormality) is associated with the assumed factor (fixation of the arm regeneration valve 28) and the default operations 1 and 2 in the storage unit 53. Remember.

FIG. 12 shows the measured features of the hydraulic excavator 100 at the time of abnormality, the theoretical features of the model 200 at the time of abnormality, and the theory of the model 51 at the normal time with respect to the average flow rate on the bottom side of the arm cylinder 16 when the default operation 1 is performed for one cycle. It is the figure which showed the feature quantity side by side. In the example shown in FIG. 12, the measured value of the average flow rate (measured feature amount) is smaller than the theoretical value (theoretical feature amount) of the average flow rate under normal conditions, and the theoretical feature obtained from the abnormal model 200 assuming oil leakage. It is within the range of quantity. From this, it is presumed that the cause of the abnormality that the average flow rate on the bottom side of the arm cylinder 16 becomes low is the oil leakage on the bottom side of the arm cylinder 16.

FIG. 13 shows the measured features of the hydraulic excavator 100 at the time of abnormality, the theoretical features of the model 200 at the time of abnormality, and the model 51 at the time of normal with respect to the average flow rate on the bottom side of the arm cylinder 16 when the default operation 2 is performed for one cycle. It is the figure which showed the theoretical feature side by side. In the example shown in FIG. 13, the measured value (measured feature amount) of the bottom side average flow rate of the arm cylinder 16 of the hydraulic excavator 100 is less than the range of the theoretical feature amount at the time of abnormality. From this, it is presumed that the cause of the abnormality that the average flow rate on the bottom side of the arm cylinder 16 becomes low is not limited to the defect of the arm regeneration valve 28.

In FIG. 14, regarding the average flow rate on the bottom side of the arm cylinder 16 when the default operations 1 and 2 are performed for one cycle, the average flow rate acquired by the hydraulic excavator in the normal state and the average flow rate acquired by the hydraulic excavator in the abnormal state are superimposed. It is a figure shown by.

As shown in FIG. 14, in the case of an abnormality caused only by an oil leak on the bottom side of the arm cylinder 16, the reduction rate of the average flow rate at the time of abnormality is calculated between the default operation 1 and the default operation 2 with respect to the average flow rate at the normal time. There is no difference. On the other hand, in the case of an abnormality caused by oil leakage on the bottom side of the arm cylinder 16 + sticking of the arm regeneration valve 28, there is a difference in the reduction rate of the average flow rate between the default operation 1 and the default operation 2. Therefore, as shown by the matrix M1 in FIG. 8, when the difference between the decrease rate of the average flow rate in the default operation 1 and the decrease rate of the average flow rate in the default operation 2 is smaller than the predetermined threshold value α, the bottom of the arm cylinder 16 An oil leak on the side is identified as a factor, and when the threshold value is α or more, an oil leak on the bottom side of the arm cylinder 16 + sticking of the arm regeneration valve 28 is identified as a factor.

FIG. 15 is a diagram showing the measured feature amount and the theoretical feature amount of the abnormal time model 200 rearranged in order of magnitude with respect to the average flow rate of the bottom side flow rate of the arm cylinder 16.

In the example shown in FIG. 15, the actual measurement value (measured feature amount) is smaller than the theoretical feature amount of the abnormal time model 200 assuming a small degree of oil leakage, and the theory of the abnormal time model 200 assuming a medium degree oil leakage. Since it is larger than the feature amount, the degree of oil leakage can be regarded as small to medium. By outputting this information to the monitor 62, the operator can grasp the degree of oil leakage.

FIG. 16 shows a hypothetical factor of an abnormality in which the boom lowering is slower than in the normal state, and a tendency of the average flow rate on the rod side of the boom cylinders 14 and 15 acquired when the hydraulic excavator having the presumptive factor performs the default operation. Is a matrix associated with.

In FIG. 16, the default operation 3 is an operation to which boom regeneration is applied (for example, an operation of lowering the boom from a boom raised state to a state where there is no external load), and a default operation 4 is an operation to which boom regeneration is not applied (for example, a jack). Up operation).

According to the matrix M2 shown in FIG. 16, the average flow rate (measured feature amount) on the bottom side of the boom cylinders 14 and 15 when the default operations 3 and 4 are performed, and the default operations 3 and 4 are performed on the abnormal model 200. By comparing with the bottom-side average flow rate (theoretical feature amount at the time of abnormality) of the boom cylinders 14 and 15 acquired in the above, the cause of the abnormality that the boom speed becomes slower than the normal time is three assumed factors (boom cylinder 14). , 15 bottom side oil leak, boom regenerating valve sticking, boom cylinders 14, 15 bottom side oil leak + boom regenerating valve sticking).

FIG. 17 is acquired when a hypothetical factor of an abnormality in which the pressure on the bottom side of the hydraulic cylinders 14 to 17 for driving the front device 101 becomes lower than in the normal state and a hydraulic excavator having the presumptive factor perform a predetermined operation. It is a matrix which corresponds with the tendency of the pressure on the bottom side of the hydraulic cylinders 14 to 17. In FIG. 17, the default operation 5 is the boom raising independent operation, the default operation 6 is the arm pulling independent operation, and the default operation 7 is the bucket cloud independent operation.

According to the matrix M3 shown in FIG. 17, the bottom pressures of the boom cylinders 14 and 15 when the hydraulic excavator 100 performed the default operation 5 were within the range of the theoretical feature amount at the time of abnormality, and the default operation 6 was performed. When the bottom side pressure of the arm cylinder 16 at the time is within the range of the theoretical feature amount at the time of abnormality, and the bottom side pressure of the bucket cylinder 17 when the default operation 7 is performed is within the range of the theoretical feature amount at the time of abnormality. , The sticking of the main relief valve 23 is identified as the cause of the abnormality.

In the matrix M3, the theoretical feature amount at the time of abnormality in the default operations 5 to 7 is obtained by causing the model 200 at the time of abnormality assuming oil leakage of the main relief valve 23 to perform the default operations 5 to 7. In the abnormal model 200 here, a leaky oil passage for discharging a part of the hydraulic oil discharged from the hydraulic pump 21 to the tank 24 in the normal model 51 is added, and a variable throttle valve is installed in this leaky oil passage. It is assumed that the throttle amount (parameter) of the variable throttle valve is adjusted according to the degree of oil leakage. The theoretical feature amount at the time of abnormality in the default operation 5 is the bottom side pressure of the boom cylinders 14 and 15 calculated by causing the model 200 at the time of abnormality to perform the default operation 5. The theoretical feature amount at the time of abnormality in the default operation 6 is the bottom side pressure of the arm cylinder 16 calculated by causing the model 200 at the time of abnormality to perform the default operation 6. The theoretical feature amount at the time of abnormality in the default operation 7 is the bottom side pressure of the bucket cylinder 17 calculated by causing the model 200 at the time of abnormality to perform the default operation 7.

In order to identify the cause of the abnormality that the pressure on the bottom side of the hydraulic cylinders 14 to 17 for driving the front device 101 is lower than that in the normal state as a defect of the main relief valve 23, the hydraulic excavator 100 performs the default operations 5 to 7. It is necessary to measure the bottom pressure of the hydraulic cylinders 14 to 17 at the time, but the default operations 5 to 7 (boom raising independent operation, arm pulling independent operation, bucket cloud independent operation) are frequently performed in normal work. Therefore, the operator does not need to additionally perform the default operation at the time of abnormality diagnosis. In this way, by setting the operation frequently performed in the normal work as the default operation, it is possible to reduce the man-hours related to the abnormality diagnosis.

In the present embodiment, the hydraulic pump 21, the hydraulic actuators 11 to 17 driven by the hydraulic pump 21, the controller 50 having a calculation function, the notification device 62 for outputting the calculation result of the controller 50, and the hydraulic actuators 11 to 11 Hydraulic pressure provided with sensors 31 to 36, 41, 42 for acquiring information output from an operation instruction device for instructing the operation of 17 or attitude information of the hydraulic excavator 100 and feature quantities indicating the operating state of the hydraulic excavator 100. In the excavator 100, the controller 50 stores the normal model 51, which is a simulation model for simulating the normal operation of the hydraulic excavator 100, and information on factors for the abnormality of the feature amount, and operates the hydraulic excavator 100. By inputting the attitude information acquired by the sensor or the information output from the operation instruction device into the normal model 51, the theoretical feature amount, which is the theoretical value of the feature amount, is calculated and detected by the sensor. Based on the result of comparison between the measured feature amount, which is the measured feature amount, and the theoretical feature amount, it is determined whether or not the measured feature amount is abnormal, and when it is determined that the measured feature amount is abnormal, An instruction for prompting a default operation necessary for identifying the cause of the abnormality is output to the notification device 62.

Further, the controller 50 calculates the deviation rate of the actually measured feature amount with respect to the theoretical feature amount, and when the deviation rate exceeds a predetermined threshold value, determines that the actually measured feature amount is abnormal.

Further, the controller 50 acquires a factor for the abnormality and an abnormality model 200, which is a simulation model for simulating the operation of the hydraulic excavator 100 having the factor, for each type of abnormality of the feature amount to perform a default operation. A plurality of matrices M1 to M3 corresponding to the tendency of the theoretical feature amount are stored, and when it is determined that the actually measured feature amount is abnormal, the measured feature amount of the plurality of matrices M1 to M3 When a specific matrix corresponding to the anomaly is selected and the tendency of the actually measured features acquired by causing the hydraulic excavator 100 to perform a predetermined operation and the tendency of the theoretical features for a specific factor in the specific matrix match. The information on the specific factor is output to the notification device 62.

According to the present embodiment configured as described above, the measured features are based on the comparison result between the measured values (measured features) and the theoretical values (theoretical features) of the features indicating the operating state of the hydraulic excavator 100. Whether or not there is an abnormality in the amount is determined, and when it is determined that there is an abnormality in the actually measured feature amount, information on the abnormality and the cause is output to the notification device 62. As a result, the operator can grasp the abnormality of the hydraulic excavator 100 and the cause of the abnormality during the operation of the hydraulic excavator 100. In the present embodiment, the abnormality information and the factor information are notified to the operator via the monitor 62, but the service staff who is remote may be notified via the communication device.

Further, the hydraulic excavator 100 according to the present embodiment is another hydraulic excavator because the abnormality determination and the cause determination are performed using the normal model 51 and the abnormal model 200 constructed according to the model and specifications of the hydraulic excavator 100. Does not require the data acquired in. This makes it possible to apply the present invention to a small number of hydraulic excavators on the market.

Further, the controller 50 operates the unexecuted default operation when there is an unexecuted default operation that the hydraulic excavator 100 has not performed so far among the plurality of default operations defined in the specific matrix. The instruction is output to the notification device 62. As a result, the operator can perform the default operation necessary for identifying the cause of the abnormality of the feature amount without omission.

In the present embodiment, the speed of the boom 5 and the arm 6 and the pressure on the bottom side of the hydraulic cylinders 14 to 17 are measured as the feature quantities of the hydraulic excavator 100, and the abnormality diagnosis of the hydraulic excavator 100 is performed. The actuator for measuring the speed is not particularly limited, and an abnormality diagnosis may be performed by measuring, for example, the bucket 7, the turning speed, and the rotation speeds of the traveling motors 11 and 12. Further, the place where the pressure is measured is not particularly limited, and for example, a failure may be determined around the pump or the like by measuring the pump pressure or the like. Further, by adding a sensor for measuring the feature amount indicating the operating state of the traveling motors 11 and 12 and the turning motor 13, and storing a matrix corresponding to the abnormality of the feature amount in the storage unit 63, the turning operation can be performed. It is possible to detect abnormalities associated with driving operations and identify the causes.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and includes various modifications. For example, the above-described embodiment has been described in detail in order to explain the present invention in an easy-to-understand manner, and is not necessarily limited to the one including all the described configurations.

1,2 ... traveling device, 3 ... traveling body, 4 ... swivel body, 5 ... boom, 6 ... arm, 7 ... bucket, 8 ... driver's cab, 9 ... machine room, 10 ... counter weight, 11,12 ... traveling motor (Hydraulic actuator), 13 ... Swivel motor (hydraulic actuator), 14,15 ... Boom cylinder (hydraulic actuator), 16 ... Arm cylinder (hydraulic actuator), 17 ... Bucket cylinder (hydraulic actuator), 21 ... Hydraulic pump, 22 ... Discharge oil passage, 23 ... Main relief valve, 24 ... Tank, 25 ... Boom direction control valve, 26 ... Arm direction control valve, 27 ... Arm regeneration oil passage, 28 ... Arm regeneration valve, 31-36 ... Pressure sensor, 41, 42 ... Stroke sensor, 50 ... Controller, 51 ... Normal model, 52 ... Abnormality determination unit, 53 ... Storage unit, 54 ... Factor determination unit, 61 ... Mode changeover switch, 62 ... Monitor (notification device), 71 ... Oil passage , 72 ... Leakage oil passage, 73 ... Variable throttle valve, 100 ... Hydraulic excavator (construction machine), 101 ... Front device, 200 ... Abnormality model.

Claims (3)

With a hydraulic pump
The hydraulic actuator driven by the hydraulic pump and
A controller with a calculation function and
A notification device that outputs the calculation result of the controller and
In a construction machine provided with information output from an operation instruction device for instructing the operation of the hydraulic actuator, attitude information of the construction machine, and a sensor for acquiring a feature amount indicating an operating state of the construction machine.
The controller
It stores a normal model, which is a simulation model that simulates the normal operation of the construction machine, and information on factors for the abnormality of the feature amount.
The theoretical feature amount, which is the theoretical value of the feature amount, is calculated by inputting the posture information acquired by the sensor or the information output from the operation instruction device into the normal state model during the operation of the construction machine. ,
Based on the comparison result between the actually measured feature amount, which is the feature amount detected by the sensor, and the theoretical feature amount, it is determined whether or not the actually measured feature amount is abnormal.
A construction machine characterized in that when it is determined that there is an abnormality in the actually measured feature amount, an instruction for prompting a default operation necessary for identifying the cause of the abnormality is output to the notification device. In the construction machine according to claim 1,
The controller
The deviation rate of the measured feature amount with respect to the theoretical feature amount is calculated.
A construction machine characterized in that when the deviation rate exceeds a predetermined threshold value, it is determined that the measured feature amount is abnormal. In the construction machine according to claim 1,
The controller
For each type of abnormality of the feature amount, a factor for the abnormality and a tendency of the theoretical feature amount acquired by performing a default operation on an abnormality model which is a simulation model simulating the operation of the construction machine having the factor. Stores multiple matrices associated with
When it is determined that the actually measured feature amount is abnormal, a specific matrix corresponding to the abnormality of the actually measured feature amount is selected from the plurality of matrices.
When the tendency of the actually measured feature amount acquired by causing the construction machine to perform a predetermined operation and the tendency of the theoretical feature amount with respect to the specific factor in the specific matrix match, the information of the specific factor is notified. A construction machine characterized by outputting to equipment.

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