JPH0570114B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is applied to a windmill-type anemometer installed in a cold region.

The present invention relates to a mechanism for preventing rotation failure due to ice and snow adhering to an anemometer.

〔overview〕

The present invention is an anemometer for use in cold regions equipped with a wind turbine, which prevents rotational failure due to icing when the wind turbine is stationary by rotating the rotating shaft of the wind turbine at a very low speed with an electric motor through means that connect it loosely even when there is no wind. It is something to do.

[Conventional technology]

Windmill-type anemometers are often used to measure weather data because the windmill can accurately track the direction of the wind and accurately measure wind speed. In addition, this type of windmill has a small rotating weight, and the number of rotations can be easily converted into an electrical signal and transmitted or recorded over a long period of time. For this reason, it is used as an anemometer that can be installed in uninhabited areas or even in manned areas that are often difficult for workers to patrol.

However, in a cold region, as shown in FIG. 5, if an icing point A occurs between the wind turbine 1 and the fuselage 3 where the wind direction tracking blade 2 is installed in a no-wind condition, the wind turbine 1 and the fuselage 3
It sticks to me.

Also, even if the wind turbine and the body do not stick together, the sixth
As shown in Figure a, each propeller blade 1A to 1 of the wind turbine 1
The amount of ice accretion in each of the points D becomes unbalanced and fluctuates from side to side as shown in Figure 6b, making the measurement of wind speed uncertain.

Conventionally, as a countermeasure against this problem, heaters R1 to R3 were installed inside the wind turbine 1 and its propeller blades, as shown in FIG.
4 to R6 are mounted, and a power source 5 supplies heat generation current to the heaters R1 to R6 from a support 4 connected via a rotating joint 3A of the body 3. This supply circuit includes a slip ring 7A,
7B and 7C were provided.

[Problem to be solved by the invention]

However, as mentioned above, in order to maintain the temperature of the wind turbine and the fuselage so that icing does not occur using the heater,
The heat output of the heater needs to be around 1KW.
Further, if a large number of slip rings as described above are provided in a circuit through which such a large current flows, the structure becomes complicated.

SUMMARY OF THE INVENTION An object of the present invention is to solve these problems and provide an anemometer for cold regions that requires less electric power, has a simple configuration, and can prevent poor measurements due to icing on the wind turbine.

[Means to solve the problem]

The present invention provides an anemometer equipped with a windmill and a rotation detection circuit that detects the rotation of the windmill and generates an electric signal, in which an electric motor is coupled through means loosely coupled to the rotating shaft of the windmill, and when there is no wind. This windmill is characterized by rotating at a very slow speed.

A means for recording or transmitting an electrical signal as a numerical value corresponding to the number of rotations per unit time is provided, and this means includes means for processing the forcibly applied slow speed as a value corresponding to the number of rotations of zero. I can do it.

The loose coupling means may include a permanent magnet attached to one rotating shaft and a magnetic plate attached to the other rotating shaft and positioned opposite the permanent magnet.

Preferably, the power supply circuit of the motor is provided with a temperature switch that automatically closes the circuit at a temperature below a predetermined temperature.

[Effect]

Rotating windmills makes it difficult for snow and ice to accumulate.

The rotational speed of the electric motor is extremely small and can be set below the error range when measuring wind speed.
Since the electric motor is coupled through a loose coupling force, when the windmill rotates due to the wind, the windmill rotates by shaking off this force and has virtually no effect on measurement accuracy.

If the coupling force with the electric motor is strong and measurement precision needs to be increased, calculations can be made to exclude this influence when processing the output signal.

When the windmill is rotated only by the electric motor, processing can be performed so that the rotation speed measured thereby becomes zero.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a cutaway view of essential parts of a first embodiment of the present invention. In this figure, a wind turbine 1 equipped with propeller blades 1A and 1C is connected to a fuselage 3 via a rotating shaft 6. The output of the rotation speed detection unit 8, which is composed of a slit disk 8A fixed to the rotating shaft 6 and a photo interrupter 8B surrounding the peripheral end of the slit disk 8A, is converted into a pulse signal by a pulse generator 8C.
The wind speed is inputted to the recording device 9 via a slip ring 7D provided between the rotating joint 3A of the fuselage 3 and the strut 4, and the wind speed is recorded. FIG. 2 shows a block diagram of this recording device 9. As shown in FIG.

Here, the feature of the present invention is that the rotating shaft 6
A magnetic body 6A fixed to the opposite end of the wind turbine 1
and a permanent magnet 10 provided opposite thereto are loosely coupled by magnetic force, and the rotating shaft 6 is connected to the electric motor 11.
Rotate it more slowly.

Furthermore, a power source 5 that supplies a driving current to the electric motor 11
The supply circuit is equipped with a temperature switch 5A that automatically closes the circuit when the air temperature near the anemometer falls below a predetermined temperature. Furthermore, in Figure 2,
In order to convert the pulse signal sent out by the pulse generator 8C into a numerical value corresponding to the number of revolutions per unit time, a counter 21 and a register 22 each input the clock 20A, and the output of the register 22 is recorded in a recording section 25. In order to process the rotation speed to a value relative to the rotation speed when the wind turbine is rotated only by the electric motor 11, a comparator 23 to which the reference value signal 20B is input and a selector 24 to which the zero value signal 20C is input is provided. That's true.

In the device of this embodiment, when the temperature falls below a predetermined temperature (for example, -3 DEG C.), the temperature switch 5A is activated and the electric motor 11 drives the permanent magnet 10 to rotate using the drive current from the power source 5. Therefore, the magnetic body 6A is magnetically loosely coupled to the permanent magnet 10, and the wind turbine 1 rotates at a slow speed even in a windless state.
Therefore, wind turbines do not freeze due to icing. In such a state, when the wind blows and the wind turbine 1 rotates faster, the electromagnetic coupling between the magnetic body 6A and the permanent magnet 10 is broken off, and the wind turbine 1 rotates due to the wind. If the rotation direction of the wind turbine 1 caused by the electric motor 11 and the rotation direction of the wind turbine 1 caused only by the wind are made the same, the influence of the rotation caused only by the electric motor will be substantially added to the recorded wind speed. Since the rotational speed for this purpose only needs to be extremely small, this rotational speed can be set within the error range when measuring wind speed.

In an anemometer that measures normal wind speed, the constant wind speed is 2 m/sec or less, so a value indicating an allowable error range, for example, a reference value, can be set to 0.5 m/sec. In addition, for light wind anemometers, the constant dynamic wind speed is
Since it is less than 0.4m/sec, the standard value is set to 0.3m/sec. Therefore, the rotation speed due to only the electric motor is
In each case, it is preferable to select a value below this reference value.

In FIG. 2, the reference value signal 20B input to the comparator 23 is not detected by a normal anemometer as described above.
0.5m/sec, and 0.3m/sec for an anemometer for measuring light winds.
sec.

Figure 3a shows a time chart of wind speed measurement records when the standard value is 0.5 m/sec using a general-purpose anemometer and the electric motor is not operating. In this figure, section L is a light wind section, and section M is a no wind section. The dashed line indicates the standard wind speed of 0.5 m/sec. When the electric motor operates here, as shown in Figure 3b, the wind is recorded as if it were generated by the rotation of the electric motor for the same amount of time in the light wind section L, and for an even longer period N in the no wind section M. be done. This waveform is output from register 22 in FIG. Therefore, the comparator 23 uses this value and the reference value signal 20B (wind speed 0.5
Corresponds to m/sec. ) is determined to be smaller than the reference value in sections L and N, so the selector 24 does not take the output of the register 22,
Select the value of the zero value signal 20C. In this way, the waveform shown in FIG. 3c is obtained.

FIG. 4 is a sectional view of a main part of a second embodiment of the present invention. This example is almost the same as the first example, but
As a means for driving a rotor 11A to which a permanent magnet 10 is fixed, an electric motor 12 having a vertical rotating shaft 12C arranged substantially vertically via bevel gears 12A and 12B is provided. This electric motor 1
2 is also supplied with a driving current from the power supply 5 via the temperature switch 5A. With this structure, the weight of the anemometer body can be reduced. Further, the power supply path for the electric motor can be fixed.

As explained above, in the two embodiments,
Although the wind speed values have been described as being recorded on the recording device 9 over a long period of time, this data can be automatically transmitted to the base using a known transmission means.

Since the rotational speed of the electric motor that forcibly drives the wind turbine is low, the capacity of the electric motor can be reduced by providing an appropriate speed reduction device. Its power supply also requires a small capacity one. Therefore, this anemometer can be easily installed in uninhabited cold regions.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to realize an anemometer that can maintain a predetermined measurement accuracy even in a cold region and that does not cause rotation failure due to icing or snow accumulation.

[Brief explanation of the drawing]

FIG. 1 is a cutaway view of the main parts of the first embodiment of the present invention. FIG. 2 is a block diagram of the recording apparatus according to the first embodiment. FIG. 3 is an explanatory diagram of a time chart of wind speed recording in the first embodiment. FIG. 4 is a cutaway view of essential parts of a second embodiment of the present invention. FIG. 5 is a diagram of icing conditions in a conventional example.
FIG. 6 is a diagram showing the state of icing on a conventional wind turbine. FIG. 7 is a diagram of a conventional heat retention device. 1...Windmill, 1A-1D...Propeller blade, 2...
... Wind tracking wing, 3 ... Fuselage, 3A ... Rotating joint, 4 ... Strut, 5 ... Power supply, 5A ... Temperature switch, 6 ... Rotating shaft, 6A ... Magnetic material, 7A ~ 7
D... Slip ring, 8... Rotation speed detection section, 8
A... Slit disk, 8B... Photo interrupter, 8C... Pulse generator, 9... Recording device, 1
0... Permanent magnet, 11, 12... Electric motor, 11A
...Rotor, 12A, 12B...Bevel gear, 1
2C... Rotating shaft of electric motor, 20A... Clock,
20B...Reference value signal, 20C...Zero value signal, 2
1... Counter, 22... Register, 23... Comparator, 24... Selector, 25... Recording section, A...
…Icing location, L, M, N… Section, R1 to R6…
…heater.

Claims (1)

[Scope of Claims] 1. An anemometer equipped with a wind turbine and a rotation detection circuit that detects the rotation of the wind turbine and generates an electric signal, comprising: an electric motor, and each rotating shaft of the electric motor and the wind turbine is connected to the An anemometer for use in cold regions, characterized in that it is provided with a coupling means that connects the windmill loosely enough to rotate the windmill at a very slow speed. 2. Means for recording or transmitting the electrical signal as a numerical value corresponding to the number of revolutions per unit time, the means including means for processing the slow speed as a numerical value corresponding to the number of revolutions of zero. Anemometer for cold regions. 3. The anemometer for cold regions according to claim 1, further comprising a temperature switch in the power supply circuit of the motor that automatically closes the circuit at a temperature below a predetermined temperature.