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CN-121977833-A - Diagnostic device

CN121977833ACN 121977833 ACN121977833 ACN 121977833ACN-121977833-A

Abstract

The present invention relates to a diagnostic device. The reference number of times is the number of times when stress is applied to the target member until the target member fails when stress is repeatedly applied to the target member by a predetermined amount. The real number of times means the number of times of applying a specific amount of stress to the target member. A damage rate is calculated for a faulty vehicle in which a fault occurs in the target member, the damage rate being a total value of a ratio of the calculated real number of times to the reference number of times for each stress applied to the target member. A histogram is created with the damage rate as a class and the number of faulty vehicles as a frequency based on the damage rates calculated for each of the faulty vehicles. The diagnostic device diagnoses that the target vehicle is highly likely to fail when the damage rate of the target vehicle is within the range of the peak zone RP, as compared with a case where the damage rate is smaller than the lower limit value of the peak zone RP.

Inventors

  • Shoya Okamoto, Kobayashi
  • An Huyangjie

Assignees

  • 丰田自动车株式会社

Dates

Publication Date
20260505
Application Date
20251027
Priority Date
20241030

Claims (5)

  1. 1. A diagnostic device for diagnosing the occurrence probability of a failure due to each characteristic at the time of manufacture of a target member which is a member to be diagnosed, characterized in that, Calculating a damage rate, which is a total value of a ratio of the calculated actual number of the stress applied to the target member provided to the vehicle to the reference number, for a faulty vehicle, which is a vehicle in which the fault occurs, based on a reference number, which is a number of times the stress is applied to the target member until the fault occurs in the target member and a real number, which is a number of times the stress is applied to the target member provided to the vehicle, measured based on a travel history of the vehicle, which is a number of times the stress is applied to the target member provided to the vehicle, which is a number of times the stress is applied to the target member in a predetermined amount, Creating a histogram having the damage rate as a rank and the number of the faulty vehicles as a frequency based on the damage rates calculated for the faulty vehicles respectively, The diagnostic device is provided with a processing circuit and a storage device, The storage means stores information relating to the histogram, The processing circuit determines that the possibility of occurrence of the failure in the target component in the target vehicle is higher than in the case where the damage rate of the target vehicle, which is a vehicle to be diagnosed, is within a range including a peak band, which is a range of the damage rate of the level having the largest frequency in the histogram, than in the case where the damage rate of the target vehicle is smaller than a lower limit value of the peak band.
  2. 2. The diagnostic device of claim 1, wherein the diagnostic device is configured to, The processing circuit determines that the possibility of occurrence of the failure on the target component in the target vehicle is lower than in a case where the damage rate of the target vehicle is greater than an upper limit value in the peak zone, than in a case where the damage rate of the target vehicle is less than a lower limit value in the peak zone.
  3. 3. The diagnostic device of claim 2, wherein the diagnostic device comprises, The processing circuit may be configured to reduce a frequency of recommending inspection of the target component to a user of the target vehicle, when the damage rate of the target vehicle is greater than an upper limit value in the peak zone, as compared to when the damage rate of the target vehicle is less than a lower limit value in the peak zone.
  4. 4. A diagnostic device as claimed in any one of claims 1 to 3, characterized in that, The target member is a bearing mounted on a crankshaft of an engine of the target vehicle.
  5. 5. The diagnostic device of claim 4, wherein the diagnostic device comprises, The amount of stress applied to the bearing is the face pressure value applied to the bearing, In a state where foreign matter is mixed in the bearing, a reference number of times of the bearing is measured in advance for each of the face pressure values, For each combination of the engine load in the engine and the rotational speed of the engine per unit time, the face pressure value applied to the bearing is measured in advance, The number of times the stress is applied to the bearing for each of the face pressure values corresponding to the combinations is observed as the real number of times according to the operation time of the engine in the vehicle measured for each of the combinations, The storage means stores information about the histogram created using the reference number and the real number.

Description

Diagnostic device Technical Field The present invention relates to a diagnostic device. Background Japanese patent application laid-open No. 2023-139965 describes a diagnostic device. The diagnostic device acquires, from a plurality of vehicles, running parameters that are information indicating the running state of the vehicle. The diagnostic device calculates a similarity of a running parameter in a certain vehicle with running parameters in a plurality of other vehicles. The diagnostic device calculates the similarity for all the vehicles for which the running parameters are acquired. The diagnostic device diagnoses that the target vehicle is at risk of failure when the degree of similarity in the vehicle to be diagnosed is a value close to the degree of similarity of the vehicle having the failure history. Disclosure of Invention As described above, in the diagnosis based on the similarity with the failed vehicle, the failure risk of each component cannot be diagnosed. The diagnostic device for solving the above-described problems is a diagnostic device for diagnosing the occurrence probability of a failure due to each characteristic at the time of manufacture with respect to a target member which is a member to be diagnosed. The reference number of times is the number of times the stress is applied until the failure occurs in the target member when a predetermined amount of stress is repeatedly applied to the target member, which is measured in advance. The actual number is the number of times the stress of the specific amount is applied to the target member provided in the vehicle, based on the travel history measurement of the vehicle. And calculating a damage rate, which is a total value of a ratio of the real number of times to the reference number of times calculated for each of the stresses applied to the target member provided to the vehicle, for a faulty vehicle, which is a vehicle in which the fault occurs in the target member, based on the reference number of times and the real number of times. Creating a histogram having the damage rate as a rank and the number of the faulty vehicles as a frequency, based on the damage rates calculated for the faulty vehicles, respectively. The diagnostic device includes a processing circuit and a storage device. The storage stores information related to the histogram. The peak band refers to the range of the damage rate of the class determined to be the most frequent in the histogram. The processing circuit determines that the possibility of occurrence of the failure in the target member in the target vehicle is higher than in the case where the damage rate of the target vehicle, which is a vehicle to be diagnosed, is within the range of the peak zone, as compared with the case where the damage rate of the target vehicle is smaller than the lower limit value of the peak zone. The diagnostic device can diagnose whether or not there is a risk of failure for each component. Drawings Features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, in which like reference numerals denote like elements, and in which: Fig. 1 is a schematic diagram showing a configuration of a diagnostic system including a diagnostic device according to an embodiment. Fig. 2 is a table showing an operation time of the engine according to a combination of the rotation speed and the load factor of the engine provided in the vehicle. Fig. 3 is a histogram of the diagnostic apparatus of fig. 1 for diagnosis. Fig. 4 is a table showing the surface pressure acting on the bearing provided in the engine according to the combination of the rotational speed and the load factor of the engine provided in the vehicle. Fig. 5 is an S-N diagram of a bearing provided in an engine. Fig. 6 is a flowchart showing a process performed by the diagnostic apparatus of fig. 1. Detailed Description Structure of diagnostic system 100 An embodiment of the diagnostic device will be described below with reference to fig. 1 to 6. As shown in fig. 1, the diagnostic system 100 is constituted by a diagnostic device 10 and a subject vehicle 20. As shown in fig. 1, the diagnostic device 10 includes a processing circuit 11 and a storage device 12. The processing circuit 11 executes various processes by executing programs stored in the storage device 12. The processing circuit 11 includes a processor. The diagnostic device 10 can diagnose a plurality of subject vehicles. The subject vehicle 20 is a vehicle to be diagnosed by the diagnostic apparatus 10. As shown in fig. 1, in a diagnostic system 100, each subject vehicle 20 includes a processing circuit 21, a storage device 22, and a communication device 23. The processing circuit 21 executes various processes by executing programs stored in the storage device 22. The processing circuit 21 includes a processor. Each subject vehicle 20 is communicably con