JPS6253776B2 - - Google Patents

Description

[Detailed Description of the Invention] This invention applies to continuous and intermittent measurements using an air micrometer or an electric micrometer. This relates to a method of automatically performing master measurement and zero adjustment.

Regarding the method of automatically performing master alignment, the applicant of the present application previously applied for patent application No. 1976-66971, but if a sudden minute abnormality occurs in the measurement system during master alignment, the reference value suddenly went crazy,
Subsequent measurements will be incorrect. Since master alignment is performed automatically, there is a danger that this may go unnoticed.

Therefore, it was considered to compare the new measured value from the master adjustment with the previous measured value and stop the measurement when it exceeds the set range and make adjustments, but readjustment takes time and effort. During this time, measurement is interrupted, resulting in a decrease in efficiency. Therefore, as a result of examining this sudden abnormality in master alignment, we found that the abnormality is caused by the adhesion of fine dust at the point to be measured on the master or the movement mechanism of the probe, or by a slight abnormal play in the movement mechanism of the probe. It was found that by repeating the master measurement several times in succession, the normal state could be returned in most cases. Therefore, this invention measures the master repeatedly when the master measurement value exceeds a predetermined range compared to the previous measurement value, thereby avoiding wasteful operations such as stopping and readjusting the measurement due to sudden abnormalities. It is an attempt to rationalize it.

In Fig. 1, the object to be measured 1,
2, 3, . Then, the probe 4 is pulled up every certain period of measurement, and the probe 4 is brought into contact with the master 5, thereby correcting the measurement reference value (hereinafter referred to as zero point correction).

Then, measurements are continued based on this corrected value. The first stored master measurement value is now a, the next master measurement value is b, and Δl is a predetermined permissible variation value. Here, Δl is the maximum value that is considered to change during the time required for a certain period of measurement when the master is affected by external influences, such as temperature changes. In the range of ba<Δl, the correction is normally performed and measurement is continued, but when ba>Δl, the master measurement operation is repeated. Only when ba>Δl occurs n times in a row, an abnormality warning is given and the measurement is stopped. Here, n is a preset number of times, and when repeating the master measurement, the probe is moved up and down each time.
Operate the probe moving mechanism. In other words, measurements are not made n times in succession while keeping the probe in contact with the master.

The above is shown in the flowchart in Figure 2, in which the master is first measured, its value a is memorized, and then the workpiece is continuously and intermittently measured using a as a reference, and measurements are performed a predetermined number of times. After that, the second
Perform the master measurement for the second time, and let the value be b. And if b-a<△l, the memory of a is b
and the measurement cycle continues. Also b
If -a<△l, count the number of times, enter the master measurement operation again, and set the new master value.
Check whether b' - a < △l for b', and if b' - a < △l, update the memory with b' as the new master value, thereby starting the measurement cycle. . If b′-a<△l, then count the number of times, repeat the above operation, continue master measurement, and when master measurement reaches n times in a row, an abnormality will be alerted. to stop the measurement.

As is clear from the above explanation, the present invention can prevent errors in master alignment from entering measurements due to unexpected causes, and can identify true accidents, greatly improving measurement efficiency. can be done.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of automatic master matching, which is the object of the present invention, and FIG. 2 is a flowchart explaining the operation of the present invention. 1, 2, 3... Workpiece, 4... Gauge, 5
...Master.

Claims (1)

[Claims] 1. In a comparison measurement in which automatic master adjustment is performed every certain period of continuous intermittent measurement, the next master value b is compared to the currently stored master value a.
is relative to the allowable value Δl, and if b-a<△l, the stored master value is changed to b and the normal measurement cycle begins; if b-a<△l, the master measurement operation is automatically performed. A master adjustment method in which a master measurement error is reported when the master measurement is repeated a set number of times.