JPS5816878Y2 - protractor - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a protractor for analyzing a graph 2 drawn on a recording paper 1 as shown in FIG. 1 using a pen recorder or the like.

A conventional protractor of this type has a circular shape like a protractor generally available on the market, and is, for example, as shown in FIG. 2.

3 is a protractor made of transparent plastic, etc. To use it, place the protractor on recording paper, align the reference line 4 of the protractor with the reference line on the recording paper, and draw a graph in the same way as a normal protractor. This means reading the slope of .

However, this method has the disadvantage that the reference line has to be aligned each time, which is cumbersome.

The purpose of this invention is to provide a protractor that eliminates the drawbacks of the conventional example described above.

An embodiment of this invention will be described with reference to the drawings.

In each figure, the same numbers are used to represent similar items.

Figure 3 shows the first embodiment of this invention, where 3 is a protractor;
5 is a scale plate made of transparent plastic, 6 is a guide plate, a spacer having a 7-digit reference plane AA', and 10 is a minute scale provided on the scale plate 5.

To use this, sandwich the recording paper 1 between the scale plate 5 and the guide plate 6, and move the recording paper while aligning the bottom edge of the recording paper with the reference plane A-A' until it is on top of the desired graph. Position the minute scale 10 on the scale plate 5 and read the slope value.

For example, when measuring reverberation time, the vertical axis of the graph is the sound pressure (dB), the horizontal axis is the time (seconds), and the reverberation time is determined from the slope of the graph. If you make time directly correspond to multiple degree scales (write them down), you can visually determine the reverberation time.

In this embodiment, the protractor 3 is obtained by bonding the scale plate 5 and the guide plate 6 via the spacer 7, but it may also be integrally molded from plastic or the like.

□・,,' Fig. 4 shows the second embodiment of this invention, and the first embodiment shown in Fig.
The difference from the embodiment shown in FIG. 3 is that the guide plate 6 shown in FIG. 3 is made approximately the same size as the scale plate 5.

Further, this guide plate 6 may be made of transparent plastic or the like and provided with a second minute scale to form a second scale plate 5'.

In this case, measurements can be made using the scale plate 5 as in the first embodiment, and two types of measurements can be made by turning the protractor over and using the second scale plate 5'.

FIG. 5 shows a third embodiment of this invention, and the first embodiment shown in FIG.
This embodiment differs from the embodiment in that a second reference plane BB' is provided by a spacer 7'.

As for how to use this, as in the first embodiment, the reference plane A-
A' can be used for measurement, and other measurements can also be made by shifting the recording paper upward and aligning the upper end of the recording paper with the reference plane BB'.

Further, the combination of the two reference planes and the upper and lower edges of the recording paper along these planes may be any combination according to the degree scale 10 on the scale plate 5.

Also, similar to the second embodiment, a second guide plate 6 is used instead of the guide plate 6.
By using the scale plate 5', for example, it is possible to measure using the reference plane A-A' and the scale plate 5, and further to make other measurements using the reference plane B-B' and the scale plate 5'. .

In this way, the protractor of this invention can read the slope of the graph simply by moving the recording paper along the reference plane, so the reference line of the protractor can be aligned with the vertical or horizontal axis of the graph every time a measurement is made. This has the practical effect of eliminating the need for it.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a recording paper to be measured, FIG. 2 is a front view of a conventional protractor, and FIGS. 3 to 5 are perspective views showing embodiments of the protractor of this invention. In the diagram: 1... Recording paper, 2... Graph,
3...Protractor, 5...Scale plate,
6...Guide plate, 7...Spacer, A
-A'...Reference plane, 10...Minute scale.

Claims (1)

[Scope of utility model registration request] A scale plate made of a transparent member and having a minute scale arranged at a constant distance from a reference surface against which one side of the recording paper is brought into contact, and a reference provided near the end of the back surface of the scale plate. The graph is composed of a spacer forming a surface and a guide plate provided on the back side of the scale plate so as to sandwich the spacer, and the graph is drawn on the recording paper by moving the recording paper along the reference plane. 1. A protractor characterized in that the slope of the protractor is configured such that the gradient of the slope can be read by a degree scale drawn on the scale plate.