JPS62172264A - Optical type anemometer - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] "Industrial application field" The present invention relates to an optical anemometer that utilizes the photoelastic effect.

[Technology in the United States] One type of anemometer that has been extremely commonly used is a propeller type anemometer as shown in Figure 2. It is rotatably supported by a vertical rotating shaft S, rotates in the direction of the wind by vertical blades W, and is configured to measure the generated voltage based on the number of rotations of the propeller P to obtain the wind speed. When such a power generating type with a constant voltage of 1 jlll is monitored, an induced IP may be generated in the copper cable C.

[Object of the Invention] An object of the present invention is to provide an optical anemometer that can determine the wind speed by an optical system so that there is no influence of induction on the monitor as described above.

Therefore, in the present invention, an element that produces a photoelastic effect due to pressure (hereinafter referred to as a photoelastic effect element) is used in the wind speed detection section, and the bending stress received by the wind pressure sensing ball is applied to the photoelastic element to utilize the photoelastic effect. , an optical fiber is used for the human-emitted light to the photoelastic element to indicate the wind speed.

The present invention will be explained below with reference to an embodiment shown in FIG.

In the figure, reference numeral 1 denotes a wind speed detection section made of a photoelastic effect element, for example, rod-shaped glass. One end of a round rod support 8 made of, for example, FRP is fixed in the wind speed detection section 1, and the other end is connected to a support and a ball. A connecting rod 22 is connected to the wind pressure sensing bulb 24 through the connecting rod 22, and the lower end of the wind speed detector 1 is fixed to the stopper I9. It is fixed on the base 7 with screws 29 . Note that 12 is a puncture interposed between the main body case 1 and the support column 8, and 18 is a threaded portion for fixing the main body.

6 is an optical fiber, 5 is a gradient index lens (rod lens), 2 is a 174 wavelength plate, 3 is a polarizer, 4 is an analyzer, 5'
is a gradient index lens, 6' is an optical fiber, and 9.1
0 is an optical component fixing stand.

A gradient index lens 5 to which an end of an optical fiber 6 is connected and a polarizer 3.1/4 length plate 2 are housed in the fixing groove of the optical component fixing table 9, and both are fixed at an angle 16.

Similarly, a gradient index lens 5' and an analyzer 4 with the end of the optical fiber 6' connected to the fixing groove of the optical component fixing table 10 are housed, and the connection 7 is stopped]7, and the optical fiber 6.6' is , is adhesively fixed 15 at the drawer portion from the main body case 1. Optical component fixing table 9.10 that stores these optical components
are fixed on both sides with the wind speed detection section 1 in between and their optical axes aligned.

The wind pressure sensing bulb 24 has a hollow portion 27, and a plate-shaped heater tape 2 containing nichrome wire is previously adhesively fixed 30 inside. Both ends of the wire are hollow parts 20 of the round rod support 8 made of FRP.
The coated heater wire I3 is pulled out from the heater wire insertion connector at the bottom through the groove 21, and is connected to the photovoltaic cell 32 housed in the photovoltaic cell case 33 via the temperature switch 28, and at the same time the vyy of the case itself ,, The heater wire 31 is arranged in a meandering manner to avoid snow accumulation.

In order to eliminate the wind speed detection travel due to snow on the fl''L1 line during the low temperature period, the above heating system is required.

When the temperature falls below a predetermined value, the temperature switch (for example, shape memory alloy!! JJ) 28 energizes the photovoltaic cell 32 to raise the temperature of the bulb, prevent snow from forming, and The surface of the case 33 is also designed to prevent power reduction due to Q& young snow.

[Operation] As is well known, when pressure is applied to a crystal or amorphous material, the refractive index changes and the way light passes through it changes.

This is called a photoelastic effect, and the present invention uses this effect.

Although not shown, light from the light emitting element is guided through an optical fiber 6 and condensed by a gradient index lens 5. The light that exits the gradient index lens 6 is randomly polarized, but the polarizer 3 converts the random light into linearly polarized light, and the 1/4 wavelength plate 2 gives the linearly polarized light an optical bias of 1/4π. and circularly polarized light.

The wind pressure sensing bulb 24 receives wind from 360° directions with the same wind speed.
The sensing bulb 24 is displaced with the wind speed detection unit 1 to which it is fixed as a support point, and due to the reaction force against the wind pressure, the amorphous, for example, rod-shaped glass of the wind speed detection unit 1 receives bending stress due to the wind. The refractive index changes. The aforementioned circularly polarized light passes through this wind speed detection unit 1, and when it passes through, it becomes elliptically polarized light with a 1/4π phase shift, and the transmitted light undergoes a change in light intensity due to a change in wind speed. The elliptically polarized light is passed through the analyzer 4, and linearly polarized light is taken out again, condensed by a gradient index lens 5', guided to an optical fiber 6', and converted into an electrical signal by a photoelectric converter (not shown). That is, a change in wind speed is detected as a change in light intensity, and δI11 is determined.

[Effects] As is clear from the above-described configuration, in the present invention, except for the DC supply circuit to the wind pressure sensing bulb, the instruments disposed in the wind pressure detection section are optical instruments, and the optical fiber is connected to the optical fiber. Since it is used for emission, there is no risk of receiving electromagnetic induction from the outside, and a wind pressure sensing bulb is used to receive wind pressure.
It operates against wind from the 3GO@ direction and can accurately indicate wind speed.

The structure can be made extremely compact compared to the conventional propeller type.

[Brief explanation of drawings]

FIG. 1 shows an embodiment of the invention. Figure 2 shows a conventional propeller-type anemometer. 1... Wind speed detection unit, 2... 1/4 length plate, 3...
Polarizer, 4...Analyzer, 5.5'...Refractive index distribution/Z, 6°6'...Optical fiber, 7...Diameter pedestal,
8...Round bar support, 9.10...Optical component fixing pedestal,
24... Wind pressure sensing ball.

Claims (1)

[Claims] (1) Fix the wind pressure sensing bulb and the wind speed detection unit consisting of a photoelastic effect element together with a support in between, fix the wind speed detection unit at a fixed position, and place the wind speed detection unit in between on one side. to 1/4
A wavelength plate, a polarizer, and a gradient index lens are arranged in this order, an analyzer and a gradient index lens are arranged in that order on the other side, and optical fibers are connected to both gradient index lenses, and light is transmitted from one of the optical fibers. An optical anemometer, characterized in that the refractive index change due to the photoelastic effect of the photoelastic effect element, which is received by the wind pressure of the wind pressure sensing bulb, is detected as a change in wind speed.