JPS6131805B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a workpiece size measuring device that displays the measured value of the workpiece size together with the dimensional tolerance range on the same display.

To be able to determine at a glance whether the workpiece whose dimensions have been set is within the dimensional tolerance range and where the workpiece dimensions are located relative to the tolerance range. In the past, a pair of movable pointers were placed around the outer periphery of the dial gauge, and these points were used to display the upper and lower limits of the tolerance range. Because of this, it is not only impossible to determine whether the workpiece dimensions fall within the tolerance range or change the display of the tolerance range unless you go to the measurement position, but it is also difficult to measure the workpiece dimensions. The master, which has been machined to the standard dimensions, must be measured in advance, and the movable pointer must be set at a distance corresponding to the positive and negative tolerances from the set pointer, so the standard dimensions may vary depending on the workpiece. Setting the tolerance range was extremely troublesome if the values were different.

In view of these conventional drawbacks, the present invention has made it possible to identify the relationship between the workpiece dimensions and the tolerance range at a position away from the measurement position, and to set the tolerance range regardless of the reference dimensions of the workpiece. The present invention provides a workpiece dimension measuring device, and examples thereof will be described below based on the drawings.

Figure 1 shows the workpiece W being converted from air pressure into an electrical signal.
1 is a block diagram showing the configuration of an air/electric air micrometer for measuring the dimensions of a workpiece W. Reference numeral 1 indicates a measuring head having a jet nozzle 1a that opens on the outer peripheral surface of a workpiece W. It is connected to an air source via a throttle valve 1b. 2
3 is a pressure detector that detects the back pressure of the jet nozzle 1a and outputs an analog signal according to the outer diameter dimension Dw of the workpiece W, and 3 converts the analog signal output from this pressure detector 2 into a digital signal. A signal output from the AD converter 3 is given to a master diameter storage circuit 4 and an arithmetic circuit 5.

The master diameter memory circuit 4 memorizes the diameter dimension of the master M that has been machined to the standard dimension, and after engaging the measuring head 1 with the outer periphery of the master M prior to measuring the dimensions of the workpiece, press the pushbutton SW. When you press
A digital signal output from the AD converter 3 is stored in an internal register as data representing the dimension value Dm of the master M. The master diameter storage circuit 4 may be a digital switch that sets and stores the diameter value of the master M. The arithmetic circuit 5 receives master diameter data Dm output from the master diameter memory circuit 4.
The deviation ΔD between the data Dw and the workpiece size data Dw output from the AD converter 3 is calculated, and data representing this deviation ΔD is output to the display section 6.

As shown in FIG. 2, this display section 6 is a display device 20 having a predetermined number of rows and rows of vertically elongated flashing elements PE each having a predetermined width, such as a commercially available multi-digit fluorescent display tube.
FG202SA2 is provided, and this display 20 displays measured dimensions and dimensional tolerances.
Therefore, the display unit 6 has a digital switch DS for setting the upper limit value U and lower limit value L of the dimensional tolerance.
1 and DS2 are provided.

FIG. 3 is a block diagram showing an example of the display section 6.
Arithmetic circuit 21 that calculates which range is to be displayed as the tolerance range from data U and L of the upper and lower limit values set in digital switches DS1 and DS2.
and the deviation △D output from the arithmetic circuit 5 are inputted to the arithmetic circuit 22 which calculates at which position the flashing element PE should be lit to display the dimensions, and the output from these arithmetic circuits 21 and 22. The display control circuit 23 displays the tolerance range and dimensional values on the display tube 20 based on the data.

The data U and L of the upper and lower limit values set in the digital switches DS1 and DS2 are given to a subtracter 24 in the arithmetic circuit 21, and the width LW of the tolerance range is calculated from the difference between the two. The half-divider 25 is the width of the tolerance range.
This is to determine whether LW is larger than the number N of flashing elements PE of the display 20. If the tolerance range width LW is larger than N, the data of the tolerance range width LW is sent to the divider 26. For example, if the width LW of the tolerance range is smaller than N, the data of the tolerance range width LW is output to the divider 27 as is. Divider 27 and arithmetic unit 2
8 and 29 are for calculating the display positions of the lower and upper limits so that even if the upper tolerance range and the lower tolerance range with respect to the reference dimension are different, the tolerance range is located at the center of the display 20. The data of the width LW is divided by 2 by the divider 27 to obtain LW/2, and the data of the width LW is divided by 2 by the divider 27, and then by the calculators 28 and 29, N/2−LW/2 and N/2+
Calculate LW/2 to calculate the lower and upper limit display positions.

On the other hand, the data of the deviation ΔD between the master dimension and the measured dimension given to the arithmetic circuit 22 is given to the arithmetic unit 30, and the deviation amount ΔD with respect to the median of the tolerance range is given to the arithmetic unit 30.
Dd is determined by the calculation ΔD-(U+L)/2. The data for this deviation amount △Dd is the tolerance width LW
When LW is smaller than N, the signal is fed directly to the arithmetic unit 32, and when the tolerance width LW is larger than N, it is divided by 1/5 by the divider 31 and fed to the arithmetic unit 32. This calculator 32 calculates the display position of the measured dimension by N/2+△Dd, and the data of the display position of the measured dimension calculated by this calculator 32 is the lower limit output from the calculation circuit 21. The display control circuit 23 along with the data of the upper limit display position
given to.

The display control circuit 23 alternately performs an operation for displaying the lower limit and upper limit and an operation for displaying the measured dimension at a predetermined cycle. In the cycle to display the lower limit and upper limit, N/2- from the first (left end) of the display 20
LW/up to the second blinking element PE and N/2+LW/
Control is performed to sequentially light up the blinking elements PE from the second to the Nth (right end), and in the cycle to display the measured dimensions, the N/2+ output from the calculator 32 is performed.
Control is performed to light up the blinking element PE at the position corresponding to △Dd.

For example, the number of flashing elements PE of the display 20 is 100.
If the tolerance is -10 to +40, the width LW of the tolerance range is 50, which is less than 100, so the lower and upper limit display points are 25 and 75, respectively, and the display surface of the display 20 is As shown in FIG. 4a, the 25th blinking element on the left and the 75th blinking element on the right are all lit. In addition, to display the measured dimension, calculate the deviation amount △Dd of the measured dimension with respect to the median value of the tolerance range from the deviation △D from the standard dimension, and then calculate the display point of the measured dimension by calculating 50 + △Dd. Since the measured dimension matches the median value of the tolerance, the indicator 20
The 50th flashing element PE, which is located approximately in the center of
The flashing element PE at a position offset from the center lights up.

On the other hand, if the measured dimension is outside the tolerance range, for example, if the tolerance is -10 to +40, but the measured dimension value has a deviation of +50 from the reference dimension, the median value of the tolerance range Since the deviation amount △Dd of the measured dimension is +35, the display point of the measured dimension shifts to the 85th flashing element PE. In this case, the 85th flashing element PE will be lit in both the tolerance range display cycle and the measurement dimension display cycle, so it will be compared to the other flashing elements as shown in Figure 4b. brightness increases,
This indicates that the measured dimension exceeds the tolerance range.

Furthermore, if the width LW of the tolerance range exceeds 100, for example, if the tolerance is between -100 and +200, the width LW of the tolerance range is reduced to 1/5 and the lower and upper boundary points are calculated. Therefore, the lower and upper boundary points are 20 and 80, respectively, as shown in Figure 4c.
Even if the tolerance range exceeds 100, the tolerance range can be displayed on the display 20. In this case, the deviation amount △ of the deviation △D from the median value of the tolerance range
Since the value of Dd is also reduced to 1/5 and the measured dimension is displayed, the display point of the measured dimension correctly represents the position of the measured dimension with respect to the lower and upper limits of the tolerance range.

FIG. 5 is a block diagram showing another embodiment of the display section 6, in which display points of measured dimensions are calculated based on the lower limit of the tolerance range. That is, the digital switch DS2 is calculated from the deviation value △D output from the computing unit 5 by the computing unit 30'.
The deviation amount ΔDl from the lower limit value of the measurement dimension is calculated by subtracting the lower limit value L set in /2-
The display position of the measured dimension is calculated by adding the amount of deviation ΔDl to LW/2. This method also allows the measured dimensions to be displayed in the correct position. Also,
The measurement points of the measurement dimensions may be determined using the upper limit value as a reference using a similar method.

As described above, in the workpiece size measuring device of the present invention, the tolerance range is displayed on the display according to the upper and lower limits of the tolerance range set in the digital switch, and the Since the deviation of the output measured dimension from the reference dimension is displayed on the display as the measured dimension,
Not only can you determine whether the workpiece dimensions are within the tolerance range and how far the workpiece dimensions deviate from the median value of the tolerance range, but you can also determine whether the workpiece dimensions are within the tolerance range or not. It has the advantage of being able to set tolerance ranges regardless of reference dimensions.

In addition, in the workpiece size measuring device of the present invention, the digital switch is set at two points located away from the center of the display by 1/2 of the width of the set tolerance range. In addition to displaying the tolerance range as a point, the dimensions are displayed by lighting up a flashing element located away from the center according to the amount of deviation between the median value of the tolerance range and the deviation of the measured dimension from the reference dimension. Because I did it like this,
Even if the size of the positive tolerance range and the size of the negative tolerance range with respect to the standard dimension are different, the tolerance range can be placed in the center of the display, and it can be determined whether the workpiece dimension is within the tolerance range. Not only is it easy to use, but it also has the advantage of being able to display the tolerance range on the display even if the tolerance range is only positive or negative and its width spans more than half of the display range of the display.

Furthermore, in the case where the display position of the upper and lower limits and the dimension display position are changed depending on the size of the width between the upper and lower limits as in the above embodiment, even if the width between the upper and lower limits changes. Since the dimensions are displayed while the display width of the tolerance range is maintained at an appropriate width, there is an advantage that the tolerance range and dimensions can be displayed on a common display device regardless of the width of the tolerance range.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the workpiece size measuring device according to the present invention, FIG. 2 is a front view of a display device provided in the display section 6 in FIG. 1, and FIG. 4a to 4c are diagrams showing the display mode of the display 20 in FIG. 3, and FIG. 5 is a block diagram showing the specific configuration of the display section 6. FIG. FIG. 2 is a block diagram showing an embodiment of the invention. 1...Measuring head, 2...Pressure detector, 3...
AD converter, 4... Master diameter memory circuit, 5... Arithmetic circuit, 6... Display unit, 20... Display unit, 21,
22... Arithmetic circuit, 23... Display control circuit, 24
...Subtractor, 25 ...Discriminator, 26, 27, 31
... Arithmetic unit, 28, 29, 30, 30', 32,
32'...Arithmetic unit, DS1, DS2...Digital switch.

Claims (1)

[Scope of Claims] 1. A workpiece dimension measuring device that measures the dimensions of the workpiece and displays the measured value together with the upper and lower limit values of the dimensional tolerance on the same display, comprising:
A display device in which a predetermined number of flashing elements are arranged in a row, a setting device for setting upper and lower limit values representing the allowable tolerance of the workpiece dimensions with respect to the standard dimensions, and a deviation of the upper and lower limit values set in this setting device. a tolerance range display control means for displaying a tolerance range by setting blinking elements on both sides located apart from the center of the display device into a specific blinking state according to 1/2; and a measuring means for measuring workpiece dimensions. , a deviation calculating means for calculating the deviation of the workpiece dimension measured by the measuring means from the reference dimension, and a deviation output from the upper and lower limit values set in the setting device or an intermediate value thereof and the deviation output from the calculating means. A dimension for displaying the workpiece dimensions by calculating the amount of deviation between the two and setting the blinking element located at a position offset from the upper and lower limits of the display point or the center of the display by the amount of deviation according to the amount of deviation to a specific blinking state. A workpiece size measuring device comprising: display control means. 2. The limit value display control means and the dimension display control means determine the positions of the upper and lower limit display points and the dimension display points with respect to the center of the display according to the magnitude of the deviation between the upper and lower limit values set in the setting device. 2. The workpiece dimension measuring device according to claim 1, wherein the workpiece dimension measuring device has a function of maintaining the display width between the upper and lower limits within an appropriate range regardless of the size of the dimensional tolerance range that changes at the same ratio.