JP2024051853A - Fault diagnosis device - Google Patents

Abstract

[Problem] To easily perform fault diagnosis. [Solution] The system includes a storage unit 22 in which fault causes 34 corresponding to fault codes 31 and cause information 25 relating to fault diagnosis methods 35 corresponding to the fault causes 34 are stored, a code receiving unit 14 for receiving input fault codes 27, a cause display unit 18 for displaying the fault causes 34 corresponding to the received input fault codes 27 in order of priority based on the cause information 25, and a diagnosis execution unit 19 for acquiring the fault diagnosis method 35 corresponding to the selected fault cause 34 based on the cause information 25 and displaying the acquired fault diagnosis method 35, where the cause information 25 has a cause weighting coefficient 36 corresponding to the priority for each fault cause 34, and the cause weighting coefficient 36 includes a coefficient representing the frequency of past faults that have occurred in the market for the target device for each combination of the fault code 31 and the fault cause 34. [Selected Figure] Figure 1

Description

This relates to a fault diagnosis device that performs fault diagnosis on a target device by referencing fault codes.

As shown in Patent Document 1, a conventional fault diagnosis device displays, in response to the input of a fault code, an overview of the fault corresponding to the fault code, a circuit diagram, the main points of the measurement work (test contents), judgment criteria, etc. An operator performs fault diagnosis by referring to the contents displayed on the fault diagnosis device.

JP 2017-198526 A

However, as the target devices become more complex, the diagnostic items (test contents, repair contents, etc.) corresponding to the fault codes become more diverse, making it difficult to diagnose faults through testing and repair. In addition, there may be multiple fault codes corresponding to a fault that has occurred in the corresponding device, and it may not be easy to input the fault codes.

The purpose of this invention is to make fault diagnosis easy.

The fault diagnosis device according to one embodiment of the present invention is a fault diagnosis device that performs fault diagnosis of a target device based on a fault code, and includes an input receiving unit that receives input of various information, a display unit that displays various information, a memory unit that stores cause information on faults corresponding to the fault codes and fault diagnosis methods corresponding to the fault causes, a code receiving unit that receives one or more of the fault codes input from the input receiving unit as input fault codes, a cause display unit that displays the fault causes corresponding to the received input fault codes on the display unit in order of priority based on the cause information, and a diagnosis execution unit that acquires the fault diagnosis method corresponding to the fault cause selected from the displayed fault causes based on the cause information and displays the acquired fault diagnosis method on the display unit, and the cause information has a cause weighting coefficient corresponding to the priority for each of the fault causes, and the cause weighting coefficient includes a coefficient representing the frequency of past faults collected in the market for the target device for each combination of the fault code and the fault cause.

With this configuration, the operator performing the fault diagnosis can select the fault causes in the order in which they are displayed and execute the fault diagnosis method corresponding to the fault cause. The fault causes corresponding to the input (selected) fault code (input fault code) are displayed in order of priority, allowing for efficient and easy fault diagnosis.

In particular, the priority of fault causes is determined based on a cause weighting coefficient that includes the frequency with which faults have occurred in the past, allowing for accurate prioritization. This allows for more efficient and easier fault diagnosis.

In addition, multiple input fault codes may be accepted, and the cause display unit may increase the cause weighting coefficient of the fault cause that is common to the multiple input fault codes.

When a common fault cause corresponds to multiple received input fault codes, the common fault cause is highly likely to be the cause of the fault. Therefore, as in the above configuration, by increasing the priority of the fault cause common to the received input fault codes and executing a fault diagnosis method corresponding to the fault cause with the high priority, fault diagnosis can be performed efficiently and easily.

The cause weighting coefficient may also reflect past fault diagnosis results.

With this configuration, the causes of failures are displayed in a priority order that takes into account past failure diagnosis results, and the failure diagnosis methods can be executed in order of the likelihood of identifying the cause of failure, allowing for efficient and easy failure diagnosis.

The cause display unit may also display on the display unit the causes of failures for which the cause weighting coefficient is equal to or greater than a predetermined value.

This configuration prevents more causes of failure than necessary from being displayed, and displays the causes of failure in order of the likelihood of identifying the cause of the failure. This simplifies the display while displaying only the necessary and sufficient information, allowing for efficient and easy failure diagnosis.

The cause display unit may also display a predetermined number of causes of the failure on the display unit.

This configuration simplifies the display by preventing more causes of failure than necessary from being displayed, while still displaying just the necessary information, allowing for efficient and easy fault diagnosis.

The cause display unit may also display questions corresponding to the displayed cause of the failure on the display unit, and change the cause weighting coefficient according to the content of the answer entered to the question.

With this configuration, the displayed causes of faults can be prioritized more appropriately based on the questions and their answers, making fault diagnosis more efficient and easy.

The diagnosis execution unit may also cause the display unit to display a display that accepts input of the fault diagnosis result of the fault diagnosis performed according to the displayed fault diagnosis method, and may repeatedly display another fault cause according to the input fault diagnosis result until the fault diagnosis is completed.

With this configuration, the fault diagnosis method corresponding to the fault cause with the highest priority is executed, and even if the fault cause is not identified, the fault diagnosis method corresponding to the fault cause with the next highest priority is executed repeatedly, thereby enabling fault diagnosis to be performed efficiently and easily.

The cause display unit may also change the cause weighting coefficient depending on the contents of the input fault diagnosis result.

This configuration allows the priority of the displayed fault causes to be more appropriately determined according to the fault diagnosis results, making fault diagnosis more efficient and easy.

The system further includes a code selection unit that stores code information related to the fault code in the storage unit, acquires the fault code related to the received input fault code as a fault code candidate that is a candidate for the input fault code based on the code information, and a code display unit that displays the fault code candidate on the display unit so that it can be selected as the input fault code, and the code display unit may display the received input fault code separately from the fault code candidate.

With this configuration, when an operator inputs an input fault code, fault codes that are possible fault codes to be input can be displayed as fault code candidates based on the fault code previously input as the input fault code. As a result, an operator can input an input fault code simply by selecting a fault code from the fault code candidates, making it easy to input the input fault code and enabling fault diagnosis to be performed efficiently and easily.

The code information may have a code weighting coefficient corresponding to a priority for each of the fault codes, and the code display unit may display the fault code candidates on the display unit in order of priority based on the code information, and the code display unit may increase the code weighting coefficient of the fault code that is highly related to the input fault code in response to the received input fault code.

This configuration allows fault code candidates to be displayed in order of relevance to the fault code already entered, simplifying the display content while facilitating the input of the fault code, allowing for efficient and easy fault diagnosis.

The association between the input fault code and the fault code may be determined based on at least one of the probability that the fault codes occur simultaneously, which is determined from data that compiles past faults that have occurred in the market for the same or similar target device, and the commonality of the causes of the fault between the input fault code and the fault code.

This configuration allows the relevance between the input fault code and the fault code to be determined with high accuracy, and fault code candidates can be displayed more accurately in order of relevance to the fault code already input.

The fault diagnosis method may be a test content or repair content for the fault diagnosis, and the diagnosis execution unit may display a test tab corresponding to the test content, a repair tab corresponding to the repair content, and a tab corresponding to a selected one of the test content or the repair content as the fault diagnosis method.

This configuration allows the display of the fault diagnosis method in a necessary and sufficient format while suppressing the amount of content displayed, making it possible to perform fault diagnosis efficiently and easily.

The causes of failures and the methods of diagnosing failures may be displayed on the display unit simultaneously and in a differentiated manner.

With this configuration, the cause of the failure and the corresponding failure diagnosis method are displayed in a manner that allows the contents to be easily confirmed, allowing for efficient and easy failure diagnosis.

FIG. 1 illustrates an example of the configuration of a fault diagnosis device. FIG. 11 is a diagram illustrating a processing flow of fault diagnosis. FIG. 13 is a diagram showing an example of a code input screen displayed on a PC. FIG. 13 is a diagram showing an example of a code input screen displayed on a mobile terminal. FIG. 13 is a diagram showing an example of a cause display screen displayed on a PC. FIG. 13 is a diagram showing an example of a cause display screen displayed on a mobile terminal.

Agricultural machinery, construction machinery, and other work vehicles, as well as various other devices, are made up of mechanical and electronic components. Even if these devices are manufactured to ensure sufficient durability and reliability, breakdowns can occur. When a breakdown occurs, a breakdown diagnosis is performed to identify the location of the breakdown and analyze the failure mechanism, after which the breakdown is repaired and design changes are considered to prevent future breakdowns.

[Outline of fault diagnosis device]
First, a fault diagnosis device 1 for diagnosing faults occurring in a tractor, which is an example of such a device (target device) such as a work vehicle, will be described with reference to FIG.

When a malfunction occurs in the tractor, the malfunction detection unit 4 detects the malfunction and a malfunction code 31 (DTC: Diagnostic Trouble Code) corresponding to the detected malfunction is displayed on the monitor 2. The malfunction code 31 is linked to the details of the malfunction and stored in advance in a code list 8 stored in the memory unit 6 of the tractor. The malfunction detection unit 4 selects the malfunction code 31 corresponding to the detected malfunction from the code list 8 and displays it on the monitor 2.

When a fault occurs in the tractor and a fault code 31 is displayed on the monitor 2, the worker performing the fault diagnosis inputs the fault code 31 into the fault diagnosis device 1 to perform the fault diagnosis. Specifically, when the fault code 31 is input, the fault diagnosis device 1 displays the fault cause 34 (PC: Possible Causes), fault diagnosis method 35, workshop manual (electronic manual) 41, circuit diagram 42, etc. The worker refers to the displayed contents and performs the fault diagnosis, such as identifying the fault location and cause and repairing the fault.

The fault diagnosis device 1 may be mounted on a management computer such as a PC (personal computer), tablet, mobile terminal (smartphone), etc. that is provided independently of the tractor, or may be a dedicated device. The fault diagnosis device 1 may also be implemented as an application on a PC, tablet, mobile terminal (smartphone), etc. Furthermore, the fault diagnosis device 1 may be mounted on the tractor.

The fault diagnosis device 1 includes a control unit 10, a display unit 11, an input reception unit 12, a code reception unit 14, a code selection unit 15, a code display unit 16, a cause display unit 18, a diagnosis execution unit 19, and a memory unit 22.

The control unit 10 includes a processor such as a CPU, and controls the operation of each functional block of the fault diagnosis device 1. The display unit 11 displays various information related to fault diagnosis. The input reception unit 12 receives input of various information from an operator or the like. The input reception unit 12 may include software switches, etc., that are displayed on the display unit 11.

The code reception unit 14 receives the fault code 31 input via the input reception unit 12 as the input fault code 27. The code selection unit 15 selects (acquires) the fault code 31 related to the fault code 31 (input fault code 27) received by the code reception unit 14 as a fault code candidate 28 that is a candidate for the input fault code 27. The code display unit 16 displays the fault code candidate 28 acquired by the code selection unit 15 on the display unit 11. Note that the code selection unit 15 and the code display unit 16 do not necessarily need to be provided, and in that case, the code reception unit 14 receives the input fault code 27 only via the input reception unit 12.

The cause display unit 18 causes the display unit 11 to display the fault cause 34 corresponding to the input fault code 27. The diagnosis execution unit 19 selects the fault diagnosis method 35 corresponding to the fault cause 34 and causes the display unit 11 to display it. The operator proceeds with the fault diagnosis according to the fault diagnosis method 35 displayed on the display unit 11.

The memory unit 22 stores code information 24, cause information 25, input fault code 27, fault code candidates 28, workshop manual 41, circuit diagram 42, etc.

The code information 24 is a collection of various information related to the fault codes 31 that has been stored in advance, and a code weighting coefficient 32 is associated with each fault code 31. The code weighting coefficient 32 is a coefficient for determining the priority of the fault codes 31.

The cause information 25 accumulates various information related to the pre-stored fault cause 34 corresponding to the fault code 31 and the fault diagnosis method 35 corresponding to the fault cause 34. In addition, the cause information 25 associates the fault diagnosis method 35 and the cause weighting coefficient 36 with each fault cause 34. The cause weighting coefficient 36 is a coefficient for determining the priority order of the fault cause 34. The priority order of the fault cause 34 is set based on the likelihood that the actual fault cause can be efficiently identified. The order in which the fault cause can be efficiently identified can be, for example, the order in which the fault cause 34 is highly likely to correspond to the actual fault cause. In addition, in fault diagnosis, there are cases in which the fault diagnosis methods 35 corresponding to multiple fault causes 34 need to be executed in a predetermined order. Therefore, the priority order of the fault cause 34 may take into consideration the procedure required to identify the cause of the fault. Furthermore, the priority order of the fault cause 34 may be adjusted so that the fault causes 34 are displayed in the order in which at least one of the work time and the work man-hours required to execute the fault diagnosis method 35 becomes smallest.

The workshop manual 41 is a pre-stored electronic manual for the tractor, and records information about the tractor's structure, such as information about tractor parts, wiring information, assembly information, and repair methods and procedures. For example, part information includes information about the part's structure and specifications, and information about where and how the part is attached to the tractor. The circuit diagram 42 is pre-stored information in the form of a drawing showing the circuit configuration, such as the relationship between each part and the wiring.

[Fault diagnosis]
Next, fault diagnosis using the fault diagnosis device 1 will be described with reference to Figures 1 and 2. Figures 3 to 6 are examples of screens displayed on the display unit 11, and in the following description, will be referred to as display screens displayed on a PC and a mobile terminal, as appropriate.

[Enter fault code]
When a fault occurs in the tractor and one or more fault codes 31 are displayed on the monitor 2, the operator performing the fault diagnosis starts the fault diagnosis by inputting the displayed fault code 31 into the fault diagnosis device 1. At this time, identification information of the target device, such as the make, model, version number (region), and type of the tractor (target device) to be diagnosed, is input from the initial screen displayed on the display unit 11 of the fault diagnosis device 1 (step #1 in FIG. 2).

Once the necessary identification information has been input, a Next button for moving to the next screen is displayed on the display unit 11. If the Next button is displayed before the necessary identification information is input, the Next button may be operated before all of the identification information required for fault diagnosis has been input, making it necessary to prompt the user to input the necessary identification information again. In this embodiment, the Next button is not displayed until all of the necessary identification information has been input, which is efficient as it avoids the display of unnecessary error messages and transitions between display screens. Note that the Next button may not be displayed, and the display screen may automatically transition to the next screen once all of the necessary identification information has been input.

It is also preferable that the identification information can be selectively input, and in this case, it is preferable that another option is determined depending on the content that has been previously input. For example, when a model is selected, only the version numbers that correspond to the selected model are displayed as options for the version number.

When all the necessary identification information has been entered, a code input screen 44 for inputting the fault code 31 is displayed, as shown in Figures 3 and 4. Here, Figure 3 shows the code input screen 44 displayed on a PC or the like, and Figure 4 shows the code input screen 44 displayed on a mobile terminal such as a smartphone.

The operator inputs one or more fault codes 31 based on the code input screen 44 (step #2 in FIG. 2). The input reception unit 12 displays the input fault code 31 as an input fault code 27 on the code input screen 44 and stores it in the memory unit 22.

At this time, the fault code 31 may be directly input into the input area 44a of the code input screen 44 of the display unit 11, which functions as the input receiving unit 12, or a part of the fault code 31 may be input into the input area 44a, whereby partially matching fault codes 31 are displayed in the code selection list 44A, and the fault code 31 may be input (received) by selecting an appropriate fault code 31 from the fault codes 31 displayed in the code selection list 44A.

When the fault diagnosis device 1 includes a code selection unit 15 and a code display unit 16, the code selection unit 15 selects (acquires) a fault code 31 that is highly related to the input fault code 27 based on the code information 24 as a fault code candidate 28 that is a candidate for the input fault code 27, and stores it in the memory unit 22. The code display unit 16 displays the acquired fault code candidate 28 in the code candidate list 44B of the display unit 11 in a form that allows selection as the input fault code 27. Then, the operator selects (accepts) the fault code 31 to be input as the input fault code 27 from the fault code candidate 28 in the code candidate list 44B as necessary. The input acceptance unit 12 displays the selected fault code 31 as the input fault code 27 on the code input screen 44 in addition to the directly input input fault code 27, and stores it in the memory unit 22.

In the code candidate list 44B, the code display unit 16 may display the fault code candidates 28 in descending order of priority. The code display unit 16 determines the priority based on the code weighting coefficient 32 of the code information 24. The code display unit 16 increases the code weighting coefficient 32 of the fault code 31 that is highly related to the input fault code 27 in response to the received input fault code 27. In other words, the code weighting coefficient 32 is assigned so as to be higher for fault codes 31 that are likely to be displayed simultaneously in a similar fault or fault codes 31 that are linked to the same fault cause 34. Specifically, the correlation between the input fault code 27 and the fault code 31 can be the probability that the fault codes 31 occur simultaneously as the fault codes 31 corresponding to the fault in a fault that occurred in the past. The probability of simultaneous occurrence is calculated as the probability that the fault codes 31 occur simultaneously based on data of faults that have occurred in the market in the past for the tractor to be diagnosed, and the higher the probability of simultaneous occurrence of the fault code 31, the higher the code weighting coefficient 32 is compared to other fault codes 31. The tractors to be diagnosed may include only the same model, but may also include models of the same type (different only in model, series, version, type, etc.). The association between the input fault code 27 and the fault code 31 may be the commonality of the fault cause 34 between the input fault code 27 and the fault code 31. In other words, when there are multiple fault causes 34 linked to the fault code 31, the more fault codes 31 are linked to the same (common) fault causes 34, the higher the commonality is determined, and the code weighting coefficient 32 of the fault code 31 with more common fault causes 34 is increased compared to other fault codes 31. As a result, the fault code candidates 28 that are likely to be displayed simultaneously with the previously input fault code 31 (input fault code 27), that is, the fault code candidates 28 that are likely to occur simultaneously, are displayed in order, making it easy to find the fault code 31 to be input. As a result, it becomes easier to input the fault code 31 to be input, and fault diagnosis can be easily performed.

As shown in FIG. 3, the input failure code 27, the code selection list 44A, and the code candidate list 44B may be displayed simultaneously on one screen on the code input screen 44. This allows the input of the input failure code 27 to be easily performed. Conversely, as shown in FIG. 4, in the case of a mobile terminal or the like with a small display screen, the input failure code 27, the code selection list 44A, and the code candidate list 44B may be displayed on separate screens. For example, on the screen on which the input failure code 27 is displayed, a predetermined operation such as operating a predetermined button displayed may be performed to transition from the screen on which the input failure code 27 is displayed to a screen on which the code selection list 44A and the code candidate list 44B are displayed. This allows information to be displayed with good operability even on a mobile terminal or the like with a small display screen, and allows the input of the input failure code 27 to be easily performed.

In the code input screen 44, when one of the displayed input fault codes 27, the fault codes 31 displayed in the code selection list 44A, or the fault code candidates 28 (fault codes 31) displayed in the code candidate list 44B is selected, detailed information of the fault code 31 (input fault code 27/fault code candidate 28) may be displayed by performing a predetermined operation such as clicking the details display button 44c. In addition, the detailed information may be displayed by clicking the fault code 31. By displaying the detailed information, the input fault code 27 can be input while checking various information, and the input fault code 27 can be input easily and accurately.

[Display of cause of failure]
When the input of all input fault codes 27 has been completed, a fault cause 34 corresponding to the input fault codes 27 is displayed. Specifically, when all input fault codes 27 have been input, a predetermined operation such as operating a diagnosis start button 44b displayed on the code input screen 44 is performed, whereby the fault cause 34 is displayed (step #3 in FIG. 2).

As shown in FIG. 5 and FIG. 6, when the diagnosis start button 44b displayed on the code input screen 44 is operated, the cause display unit 18 causes the display unit 11 to display a cause display screen 45. The cause display unit 18 causes the display unit 11 to display, on the cause display screen 45, one or more fault causes 34 corresponding to the input fault code 27 and a diagnosis content screen 45A.

The fault causes 34 are candidate fault causes, and are displayed in order of priority. The cause display unit 18 determines the priority according to the cause weighting coefficient 36 of the cause information 25. The priority is determined in order of the likelihood that the fault location and fault content can be found by fault diagnosis.

When displaying the fault cause 34, the cause display unit 18 may display questions on the display unit 11. The questions are displayed corresponding to at least one of the fault code 31 and the fault cause 34. The worker inputs answers to the questions, and the cause display unit 18 changes the cause weighting coefficient 36 of the corresponding fault cause 34 according to the answers. In other words, if there is a possibility that the priority of the fault cause 34 may change by performing a simple check, the questions are displayed, and the cause weighting coefficient 36 is changed according to the answers to reflect the priority. Therefore, the order of the displayed fault causes 34 may change depending on the answers to the questions. This makes it possible to perform fault diagnosis in order of the highest possibility of finding the fault location and the fault content, making it easier for the worker to select the fault cause 34, and making it possible to perform fault diagnosis efficiently.

It is effective to display the questions when multiple failure causes 34 are linked to one failure code 31 (input failure code 27). The questions include confirmation of the failure symptoms, past repair history, etc. These questions and their answers can narrow down the failure causes 34, and the cause weighting coefficient 36 is changed accordingly.

In addition, the questions may also be assigned a priority, and the questions may be displayed in order of priority. The priority of the questions may be assigned in accordance with the priority of the failure causes 34. Furthermore, the priority of the questions may take into account the ease of checking the questions, etc.

The operator selects one of the fault causes 34 displayed on the cause display screen 45 (step #4 in FIG. 2). At this time, since the fault causes 34 are displayed in order of priority, it is preferable for the operator to select the fault cause 34 displayed at the top (first). The diagnosis execution unit 19 obtains the fault diagnosis method 35, which is the content of the fault diagnosis corresponding to the selected fault cause 34, from the cause information 25, and displays it on the display unit 11 as a diagnosis content screen 45A (step #5 in FIG. 2).

The diagnosis content screen 45A includes a test tab 45a and a repair tab 45b. When either the test tab 45a or the repair tab 45b is selected, the cause display unit 18 displays the test or repair content corresponding to the selected test tab 45a or repair tab 45b on the diagnosis content screen 45A. The diagnosis content screen 45A also includes a manual display button 45c and a circuit diagram display button 45d. Furthermore, the diagnosis content screen 45A may display one or more reference screens 45E as necessary. The reference screens 45E are images of the parts to be tested (repaired), parts to be operated during testing (repair), and their surroundings.

When the test tab 45a is selected, the cause display unit 18 causes the display unit 11 to display the test content display 45B, the reference value display 45C, and the result input screen 45D as the test content 38 displayed on the diagnosis content screen 45A. The test content display 45B is the content of the test performed to determine whether the selected fault cause 34 is the cause of the fault. The reference value display 45C displays the input value in this test and the reference value that is the range of normal values to be output. Note that depending on the test content, there may be no reference value, and the reference value display 45C may not be displayed. The result input screen 45D is a screen for inputting the results (output values) of the test performed according to the fault diagnosis method 35.

When the repair tab 45b is selected, the cause display unit 18 displays the contents of the repair to be performed to confirm the cause of the failure as the repair contents 39 displayed on the diagnosis contents screen 45A. The repair contents may include a method of confirming how the corresponding part will operate if it becomes normal as a result of the repair.

In this way, the diagnosis content screen 45A is provided with a test tab 45a and a repair tab 45b, and the fault diagnosis method 35 corresponding to the selected tab is displayed, resulting in a simple display that allows the operator to easily understand the contents of the fault diagnosis to be performed.

As shown in FIG. 5, in the diagnosis content screen 45A, the fault cause 34 and the diagnosis content screen 45A may be displayed simultaneously on one screen. This allows the selected fault cause 34 and the fault diagnosis method 35 corresponding to the fault cause 34 to be easily understood. Conversely, as shown in FIG. 6, in the case of a mobile terminal or the like with a small display screen, the fault cause 34 and the diagnosis content screen 45A may be displayed on separate screens. For example, on the screen displaying the fault cause 34, a predetermined operation such as operating a displayed predetermined button may be performed to transition from the screen displaying the fault cause 34 to the screen displaying the diagnosis content screen 45A. This allows information to be displayed with good operability even on a mobile terminal or the like with a small display screen, and fault diagnosis can be easily performed.

[Performing fault diagnosis]
When the fault diagnosis method 35 is displayed, the operator performs fault diagnosis in accordance with the displayed fault diagnosis method 35 (step #6 in FIG. 2).

First, the operator selects the test tab 45a on the cause display screen 45. When the test tab 45a is selected, the diagnosis execution unit 19 displays the test contents 38 on the diagnosis contents screen 45A. The operator then performs the test by referring to the displayed test contents 38 (step #7 in FIG. 2). The test includes measuring the current value of a specified component when a specified operation is performed. During the test, the operator can operate the manual display button 45c to display the workshop manual 41 as a reference for the test, and the circuit diagram display button 45d to display the circuit diagram 42. The workshop manual 41 and the circuit diagram 42 may be displayed as sub-screens on the cause display screen 45, or may be displayed on a screen transitioned to from the cause display screen 45.

When the test is performed, the operator inputs the test results as a response to the medical interview into the diagnosis content screen 45A (step #8 in FIG. 2). For example, if the test results are to be used as a reference value, the operator inputs the output value, which is the test result, into the result input screen 45D. The diagnosis execution unit 19 determines whether the input value meets the reference value, and indicates whether the test results are good or not by using the color, etc., of the result input screen 45D.

The diagnosis execution unit 19 displays a Yes button 45e and a No button 45f on the diagnosis content screen 45A as a question. If the test results are good, the worker operates the Yes button 45e on the diagnosis content screen 45A, and if the test results are not good, the worker operates the No button 45f on the diagnosis content screen 45A to input the test results as a response to the question. If the test results 38 do not have a reference value, the worker refers to the test contents 38 to determine whether the test results are good or not. If the test results are good, the worker operates the Yes button 45e on the diagnosis content screen 45A, and if the test results are not good, the worker operates the No button 45f on the diagnosis content screen 45A to input the test results.

The diagnosis execution unit 19 judges whether each of the fault causes 34 displayed on the cause display screen 45 is the cause of the fault, depending on the test results. In other words, if the test results are not good, it can be judged that the selected fault cause 34 is one of the causes of the fault that occurred in the tractor. It can also be judged from the test results whether other fault causes 34 may be the cause of the fault. If the test results are good, it can be judged that the selected fault cause 34 is not the cause of the fault. Then, depending on the result of the judgment, the diagnosis execution unit 19 performs a diagnostic display (status display) for each fault cause 34 displayed on the cause display screen 45, identifying whether it is the cause of the fault or is unrelated to the fault. The diagnostic display may include information on whether a repair has been performed. Furthermore, the fault cause 34 judged to be unrelated to the fault may be deleted from the diagnosis content screen 45A.

If the test results are not good (step #8 No in FIG. 2), the diagnosis execution unit 19 displays repair details 39 on the diagnosis details screen 45A, either automatically or in response to the operator's operation of the repair tab 45b. The operator then refers to the displayed repair details 39 and repairs the relevant parts, etc. (step #9 in FIG. 2). Repairs include replacing or cleaning the parts, etc.

The worker refers to the repair details 39 and checks whether the repair results are satisfactory. If the repair results are satisfactory, the worker operates the Yes button 45e on the diagnosis details screen 45A, and if the repair results are not satisfactory, the worker operates the No button 45f on the diagnosis details screen 45A to input the repair results. Alternatively, the diagnosis execution unit 19 may display buttons on the diagnosis details screen 45A for inputting whether all of the failure causes 34 have been resolved, whether some of the failure causes 34 have been resolved, or whether none of the failure causes 34 have been resolved, as a medical question, and the worker may operate the corresponding one of these buttons as a response to the medical question.

The diagnosis execution unit 19 judges whether each of the failure causes 34 displayed on the cause display screen 45 is the cause of the failure according to the repair result. Then, as in the case of testing, the diagnosis execution unit 19 performs a diagnostic display (status display) for each of the failure causes 34 displayed on the cause display screen 45 according to the result of the judgment, to identify whether the cause may be the cause of the failure or is unrelated to the failure. The diagnostic display may include information on whether repair has been performed. Furthermore, the failure cause 34 judged to be unrelated to the failure may be deleted from the diagnosis content screen 45A. The cause display unit 18 may also change the cause weighting coefficient 36 according to the contents of the input failure diagnosis result. As a result, the failure causes 34 are arranged based on the priority order reflecting the results of the already performed failure diagnosis, and the failure diagnosis can be performed more efficiently and accurately.

When making repairs, just as during testing, the manual display button 45c can be operated to display the workshop manual 41 as a reference for the repair, and the circuit diagram display button 45d can be operated to display the circuit diagram 42.

Repairs may be performed if the test results are not satisfactory, but repairs may be performed starting from the repair corresponding to the selected cause of failure 34 without testing. When repairs are performed without testing, a confirmation screen may be displayed on the display unit 11, and repair details 39 may be displayed without testing by performing an operation to perform repairs without testing.

If the test results are good (step #8 Yes in FIG. 2) and repairs have been performed, the worker checks whether all of the causes of failure 34 have been eliminated (step #10 in FIG. 2). Specifically, the worker checks the diagnostic display (status) of the causes of failure 34 displayed on the cause display screen 45, and checks whether there are any causes of failure 34 that are displayed as possibly being the cause of the failure, thereby checking whether all of the causes of failure 34 have been eliminated.

If all the fault causes 34 have not been eliminated (step #10 No in FIG. 2), the operator selects the next fault cause 34 to be tested or repaired from among the fault causes 34 displayed as possible fault causes (step #11 in FIG. 2). Since the fault causes 34 are displayed in order of priority, it is preferable to select the fault cause 34 displayed as the most likely fault cause. At this time, the cause display unit 18 may change the cause weighting coefficient 36 of the cause information 25 according to the results of the test or repair, and correct the display order of the fault causes 34. Then, the diagnosis execution unit 19 displays the fault diagnosis method 35 corresponding to the selected fault cause 34 on the diagnosis content screen 45A, and repeats the process from step #5 onwards until all the fault causes 34 are eliminated (trouble diagnosis is completed).

If all fault causes 34 have been eliminated (step #10 in Figure 2: Yes), the fault diagnosis is terminated.

When the fault diagnosis is completed, the diagnosis execution unit 19 displays a summary report on the display unit 11. The summary report organizes and displays the history entered by the worker during testing and repair, as well as the order, summary, and results of the tests and repairs performed. By displaying such a summary report, the worker can easily check the history of the fault diagnosis, which can be used as a reference for diagnosing another fault in the future, and the fault and its cause can be easily analyzed.

As described above, by displaying the fault causes 34 corresponding to the input fault code 31 in order of their likelihood of causing the fault, the operator can easily select the fault cause 34 for which the fault diagnosis is to be performed.

In addition, the fault diagnosis method 35 corresponding to the selected fault cause 34 is displayed on a single screen with only the test tab 45a, repair tab 45b, and the content corresponding to the selected tab, so that the operator can check the necessary information on a single screen and perform fault diagnosis easily and efficiently.

[Another embodiment]
(1) In the above embodiment, the cause weighting coefficient 36 may include a coefficient representing the frequency of past failures collected in the market for the target device for each combination of the failure code 31 and the failure cause 34. A history of past failures is kept as a report when inspection and repair are performed. This report contains information such as symptoms, the location of the failure, the state of the failure, the method of diagnosis, and the contents of the repair. The weighting coefficient is generated by quantifying the contents of these reports.

There may be a high possibility that a fault that has occurred in the past will occur again. In addition, a fault cause 34 that is diagnosed as the cause of a fault in a fault diagnosis when a certain fault code 31 is displayed can be considered to have a high possibility of becoming the cause of a fault when that fault code 31 is subsequently displayed. Therefore, as described above, by determining the priority taking into account the frequency of past faults collected in the market, it is possible to more accurately display the fault causes 34 in order of priority. As a result, fault diagnosis can be performed easily and efficiently.

(2) In each of the above embodiments, the cause display unit 18 may display only the failure causes 34 whose cause weighting coefficient 36 is equal to or greater than a predetermined value. In addition, the cause display unit 18 may display a predetermined number of failure causes 34, for example, five or less, on the cause display screen 45.

This prevents the fault cause 34 from being displayed more than necessary, allowing fault diagnosis to be performed easily and efficiently.

(3) In each of the above embodiments, the cause weighting coefficient 36 may include a coefficient that takes into account the history of past fault diagnoses (medical interview history). This makes it possible to more accurately display the fault causes 34 in order of priority, and to perform fault diagnosis easily and efficiently.

The medical interview history is a history of collected interview contents and results for each fault diagnosis. The relationship between the symptoms of a fault, the fault code 31, and the fault cause 34 is likely to be similar not only between the same model, but also between models of the same type that have commonalities. Therefore, the medical interview history may be collected for each group consisting of the same model and models that have commonalities, and the weighting coefficient may be generated taking into account the medical interview history collected for each group.

(4) In each of the above embodiments, the diagnosis execution unit 19 may display fault code candidates 28 that take into account the results of testing and repairs on the cause display screen 45, in consideration of cases where it may become necessary to input a new fault code 31 depending on the results of testing and repairs. In this case, the diagnosis execution unit 19 may display a search and input field for the fault code 31 on the cause display screen 45.

(5) In each of the above embodiments, the fault diagnosis device 1 is not limited to being composed of the above-mentioned functional blocks, and may be composed of any functional blocks. For example, each functional block of the fault diagnosis device 1 may be further subdivided, or conversely, some or all of the functional blocks may be combined. Furthermore, the functions of the fault diagnosis device 1 are not limited to the above-mentioned functional blocks, and may be realized by a method executed by any functional block. Furthermore, some or all of the functions of the fault diagnosis device 1 may be composed of software. A program related to the software is stored in any storage device such as the storage unit 22, and is executed by a processor such as a CPU provided in the fault diagnosis device 1, or a processor provided separately.

(6) In each of the above embodiments, the fault diagnosis device 1 can be applied to fault diagnosis of various target devices, not limited to tractors, such as various agricultural vehicles such as combines and rice transplanters, various agricultural work machines, and other work vehicles and work machines that perform other tasks.

This invention can be applied to fault diagnosis of the target device.

REFERENCE SIGNS LIST 1 Fault diagnosis device 11 Display unit 12 Input reception unit 14 Code reception unit 15 Code selection unit 16 Code display unit 18 Cause display unit 19 Diagnosis execution unit 22 Memory unit 24 Code information 25 Cause information 27 Input fault code 28 Fault code candidate 31 Fault code 32 Code weighting coefficient 34 Fault cause 35 Fault diagnosis method 36 Cause weighting coefficient 38 Test content 39 Repair content

Claims (13)

A fault diagnosis device that performs fault diagnosis on a target device based on a fault code,
an input receiving unit that receives input of various information;
A display unit that displays various information;
a storage unit for storing cause information relating to a fault cause corresponding to the fault code and a fault diagnosis method corresponding to the fault cause;
a code receiving unit that receives the one or more fault codes input from the input receiving unit as input fault codes;
a cause display unit that displays, on the display unit, the causes of the failure corresponding to the received input failure code in order of priority based on the cause information;
a diagnosis execution unit that acquires, based on the cause information, a fault diagnosis method corresponding to the fault cause selected from the displayed fault causes, and causes the display unit to display the acquired fault diagnosis method;
the cause information has a cause weighting coefficient corresponding to a priority order for each of the failure causes,
The cause weighting coefficient includes a coefficient representing a frequency of occurrence of a failure in the past collected in the market for the target device for each combination of the failure code and the failure cause. A plurality of said input fault codes are accepted;
2. The fault diagnosis device according to claim 1, wherein the cause display unit increases the cause weighting coefficient of the fault cause that is common to a plurality of the input fault codes. The fault diagnosis device according to claim 1, in which the cause weighting coefficient reflects past fault diagnosis results. The fault diagnosis device according to claim 1, wherein the cause display unit displays the fault causes whose cause weighting coefficient is equal to or greater than a predetermined value on the display unit. The fault diagnosis device according to claim 1, wherein the cause display unit displays a predetermined number of fault causes on the display unit. The fault diagnosis device according to claim 1, wherein the cause display unit displays questions corresponding to the displayed fault cause on the display unit, and changes the cause weighting coefficient according to the content of the answer entered to the question. The fault diagnosis device according to any one of claims 1 to 6, wherein the diagnosis execution unit causes the display unit to display a display for accepting input of the fault diagnosis result of the fault diagnosis performed according to the displayed fault diagnosis method, and repeats displaying another fault cause according to the input fault diagnosis result until the fault diagnosis is completed. The fault diagnosis device according to claim 7, wherein the cause display unit changes the cause weighting coefficient according to the contents of the input fault diagnosis result. Code information relating to the fault code is stored in the storage unit,
a code selection unit that acquires the fault code related to the received input fault code as a fault code candidate that is a candidate of the input fault code based on the code information;
a code display unit that displays the fault code candidates on the display unit so that the fault code candidates can be selected as the input fault code,
2. The fault diagnosis device according to claim 1, wherein the code display unit displays the received input fault code in a manner distinguished from the fault code candidates. the code information has a code weighting coefficient corresponding to a priority for each of the fault codes,
The code display unit displays the fault code candidates on the display unit in order of priority based on the code information,
10. The fault diagnosis device according to claim 9, wherein the code display unit increases the code weighting coefficient of the fault code having a high degree of relevance to the received input fault code in response to the received input fault code. The fault diagnosis device according to claim 10, wherein the correlation between the input fault code and the fault code is determined based on at least one of the probability that the fault codes occur simultaneously, which is obtained from data that compiles past faults that have occurred in the market for the same or similar target device, and the commonality of the fault causes between the input fault code and the fault code. the fault diagnosis method is a test content or repair content for the fault diagnosis,
2. The fault diagnosis device according to claim 1, wherein the diagnosis execution unit displays, as the fault diagnosis method, a test tab corresponding to the test content and a repair tab corresponding to the repair content, and a tab corresponding to a selected one of the test content or the repair content. The fault diagnosis device according to claim 12, wherein the fault causes and the fault diagnosis methods arranged in sequence are displayed on the display unit simultaneously while being distinguished from each other.

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