JPS5846687B2 - Shijikei Kiyomi Torisouchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a reading device that automatically and accurately reads numerical values from an indicating instrument in digitized form.
This is particularly effective when the dynamic characteristics of a meter such as an indicating sound level meter or a VU meter have an important meaning for the reading device.

Conventionally, when measuring the level of a signal that fluctuates greatly over time, such as voice or noise, the standard for displaying this is as follows:
VU meters, sound level meters (Japanese Industrial Standards JIS-C-1502), etc. were established as indicating instruments with certain dynamic characteristics, and the standard for level measurement was established based on the motion of this pointer.

This is due to the fact that conventionally, the main function of measurement was to be read by the human eye.

However, when a computer collects and processes data or transmits data to a remote location, it is necessary to obtain measured values as electrical signals.

Conventionally, for this purpose, the electrical signal at the input end of the indicating instrument has been used as a substitute for the above electrical signal, but apart from the fidelity of the numbers, the numerical value that is the evaluation standard originally does not reflect the dynamic characteristics of the pointer of the indicating instrument. However, this electrical signal did not include it, so it was inappropriate as a numerical value.

The present invention eliminates the above-mentioned drawbacks of the conventional technology.The present invention is capable of reading data manually and conforms to standards and regulations (for example, International Electrotechnical Standard No. 179). This makes the same evaluation method possible.

That is, the present invention optically detects and measures the pointer of an indicating instrument that rotates around a pivot.

One embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows an example of the configuration. In Figures 1 and 2, 1
~4 are the parts that make up a normal indicator, 1 is the housing, 2
3 is a scale plate, 3 is a rotatable pointer, and 4 is a pointer drive unit, which is separated from, for example, a permanent magnet and a moving coil.

Further, 5 is a light-shielding plate installed above the scale plate 2, 6 is an arc-shaped slit provided in the light-shielding plate 50, 7 is a semi-conical mirror whose inner surface is a mirror surface, and 8 is a linear photo It is an array of diodes.

Now, let me explain the operation.

In a conventional normal indicating instrument, the pointer 3 is moved by an input signal from somewhere.

Accordingly, a portion of the pointer 3 becomes an image that passes through the slit 6 and is projected onto the photodiode array 8 by the semi-conical mirror 7.

Since the movement of the pointer 3 is a rotational movement, if the photodiode array 8 is installed on a straight line, the rotational movement must be converted into a linear movement.

The semi-conical mirror 7 serves this purpose.

In this case, if the semi-conical mirror 7 whose inner surface is a mirror surface has an ridgeline of 45°, the above object is achieved.

On the other hand, in the photodiode array 8, minute segments are arranged, and a pointer 3 is projected onto this.
The image is obtained with segments corresponding to the rotation angle.

The output of each segment is fed into a matrix-forming network according to the required digital code and is digitally converted in the process.

For example, FIG. 3 is an example.

In FIG. 3, 11 is a clock pulse generator, and 12 is an example of a photodiode array, which is a combination of an 8-bit serial shift register and a photodiode.

13 is a binary counter having outputs of 12, 4, and 8, respectively.

14 is the intersection of the circles at the IJ Lux path (which has an AND circuit).

Now, when the image of the pointer 3 is located at the fourth position of the photodiode array 12, an output is obtained by the fourth clock pulse, and a digital output is obtained by ANDing with the output (4th position) of the binary counter 13.

Of course, in other cases there is no output.

In this way, with this configuration, direct analog-to-digital conversion can be performed.

Note that, depending on the method of coupling the matrix circuits, any code format, logarithmic conversion, etc. can be performed at the same time.

As explained above, according to the present invention, since the rotational movement of the pointer is detected and displayed optically, it is possible to perform the same evaluation as the conventional visual reading of numerical values, while direct analog-to-digital conversion is possible, which is very practical. It becomes convenient.

Further, in the present invention, since the image of the pointer is reflected by the semi-conical mirror, there is an advantage that the projected image of the pointer is not distorted.

In addition, in the present invention, the indicating instrument only needs to be provided with a light-shielding plate having a slit, a semi-conical mirror, and a linear photodiode array, which simplifies the structure and has the advantage of being able to continuously detect the displacement of the pointer. It has the following.

[Brief explanation of the drawing]

Fig. 1 shows an indicator reading device according to an embodiment of the present invention, in which a is a sectional view, b is a partially cutaway plan view, Fig. 2 is a perspective view of the device, and Fig. 3 is an electrical diagram of the device. It is a system diagram. 3... pointer, 5... light shielding plate, 6...
...Slit, 7...Semi-conical mirror, 8.
...Photodiode array 13...
Counter, 14... Matrix circuit.

Claims (1)

[Claims] 1. An indicating instrument having certain dynamic characteristics, a light shielding plate provided on the front side of this indicating instrument, and an arc-shaped slit 1 formed on the light shielding plate, fixed on the light shielding plate and passing through the slit. a semi-conical mirror that reflects an image of the pointer of the indicating instrument obtained by the method; and a linear photodiode 1 that receives the image of the pointer reflected by the semi-conical mirror.
An indicator reading device comprising a digital converter and a digital converter for converting the output of the photodiode array into a digital quantity G.