JPS614923A - Quality deciding method of unit for vehicle - Google Patents

Abstract

PURPOSE:To decide accurately on the border of a normalcy range by testing one objective body plural times and providing a conditional normalcy range for every normalcy range, and deciding whether the tested body is normal or not according to a combination of plural measurement data. CONSTITUTION:When factors (a)-(d) are taken as to plural measurement items, e.g. A, B, and C, normalcy ranges 1 of the factors (a)-(d) and conditional normalcy ranges 3 near the border are determined as to the item A; and the overlap range of the ranges 1 is determined as a total normalcy range 2 and th overlap range of the ranges 3 is determined as a total conditional normalcy range 4. Then, ranges 3 and 4 are determined similarly as to the items B and C; it is decided that the tested body is nomal when data on the items A-C are all within the range in the 1st measurement or defective when >=2 of the data A-C are within the range 2 and there is no data without the range 4. Then, it is considered that the data A is within the range 2 when the data A is within the range 4 and the data B is within the range 2.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a method for determining the quality of a vehicle unit, and more particularly, to a method for determining the quality of a vehicle unit, and more specifically, a method for performing a shipping inspection on a line of assembled finished products of an engine or transmission unit by measurement using a sensor. This invention relates to improvements in methods for determining the quality of products.

[Prior art]

Conventionally, this type of vehicle unit quality determination method has been carried out as shown in FIG. In Figure 1,
A, B, and C are measurement items.

Parts (a), (c), (ii) and (ii) are based on various factors, and (e) is the case when these various factors are combined. The horizontal line represents the measured data value from 0 to 100%, where 1 indicates the normal range for various factors, and 2 indicates the normal range when they are combined.

Next, the conventional pass/fail determination method described above will be explained.

For measurement item A, the normal range l is determined for each of various factors (a), (b) and (b). Next, the range where these overlap, ie, the total normal range 2, is determined. If the data of measurement item A is within the overall normal range, it is determined to be normal, that is, good. In this way, each measurement item A, B, C
Determine the overall normal range for each item. At the time of determination, when all measurement data of each measurement item A, B, and C are within the overall normal range 2, the product is determined to be non-defective.

The conventional judgment method is performed as described above, but in reality it is difficult to clearly determine the boundaries of the normal range for any measurement item, and there are ranges that are difficult to judge depending on the condition of the test object or sensor. There are many things to do. In reality, from the viewpoint of quality control safety, there is a tendency to narrow the normal range, and the quality level is made higher than necessary, resulting in a high defect rate.

[Summary of the invention]

The present invention aims to eliminate the drawbacks of the conventional ones as described above, and has been made to obtain a necessary and sufficient quality level. The present invention provides a method for determining the quality of a vehicle unit, which is characterized in that the final quality determination is performed by combining the determinations of each measurement item.

[Embodiments of the invention]

Hereinafter, one embodiment of the method for determining the quality of a vehicle unit according to the present invention will be described in more detail.

FIG. 2 shows a determination method according to an embodiment of the present invention. In Figure 2, A, B, and C indicate measurement items in the same way as in Figure 1, A, B, and H represent various factors, and E represents a combination of various factors A, B, and H. It shows the case. The horizontal line represents the measured data value from 0 to 100 (%), where 1 is the normal range for various factors and 2 is the normal range for various factors.
indicates the normal range when these are combined, 3 indicates the conditional normal range in the case of various factors, and 4 indicates the conditional normal range when they are combined.

Next, the method of determination in the determination method of the present invention will be explained.

For measurement item A, a normal range l is determined for each of various factors (a), (b) and (b), and an unclear part near the boundary is determined as a conditional normal range (3). Next, the overlapping range of normal range 1, that is, the overall normal range 2, and the overlapping range of conditional normal range 3, that is, the overall conditional normal range 4.
Determine. In this way, for all measurement items A, B, and C, the total normal range 2 and the total conditional normal range 4 are obtained, respectively.
Establish. Then, when making a judgment, the judgment is made based on the combination of the range of measurement data in each case of A, B, and C, and the judgment criteria are, for example: 1) All measurement items of A, B, and C 2) If the measurement data for any two or more of the measurement items A, B, and C are within the overall normal range 2, the product is considered good. 3) If the data for the measurement item A is within the comprehensive conditional normal range 4, and the data for the measurement item B is within the overall normal range 2, the product is good. The data is assumed to be within the overall normal range 2, and the judgment is made based on the criteria in items 1) and 2) above. This criterion is determined on a case-by-case basis depending on the content and number of measurement items.

〔Effect of the invention〕

As explained above, according to the present invention, the judgment criteria are expanded to include unclear parts near the boundaries of the conventional normal range as conditional normal ranges, and the optimum combination judgment criteria are provided for various types of monitors. Since the quality of a vehicle unit, such as an engine, is judged based on this, delicate test results can be utilized for judgment, and the accuracy of judgment can be improved.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram illustrating a conventional method for determining the quality of a vehicle unit, and FIG. 2 is an explanatory diagram illustrating a method for determining the quality of a vehicle unit according to an embodiment of the present invention. 1... Normal range, 2... Overall normal range, 3... Conditional normal range °, 4... i conditional normal range. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Claims] In vehicle unit testing, multiple tests are conducted on a single specimen, a new conditional normal range is established for each normal range, and the quality of the test is determined by combining multiple measurement data. How to judge the quality of vehicle units.