CN201340001Y - Smoke exhaust ventilator capable of automatically adjusting air exhaust speed according to oil smoke concentration - Google Patents

Abstract

The utility model relates to a range hood which automatically adjusts the exhaust speed according to the concentration of oil fume, which comprises a range hood main body and a oil fume detection control device. The oil fume detection control device is installed on the range hood main body. The oil fume detection control device includes photoelectric detection The unit and the control circuit, the range fume host at least includes an exhaust device; the photoelectric detection unit is connected to the control circuit, and the control circuit is connected to the exhaust device. The utility model utilizes the principle that the light intensity attenuation is caused by the absorption and reflection effect of the oil fume, adopts the photoelectric detection method to measure the oil fume concentration, and converts the change of the oil fume concentration into an electrical signal and outputs it to the control circuit, and the control circuit adjusts the ventilation device accordingly. The exhaust speed can be adjusted automatically according to the concentration of oil fume, which has the advantages of saving electricity and labor, high efficiency of oil fume removal, and low cost.

Description

Range hood that automatically adjusts the exhaust speed according to the concentration of oil fume

technical field

The utility model relates to a range hood, in particular to a range hood which can automatically adjust the exhaust speed according to the concentration of oil fumes.

Background technique

With the improvement of people's living standards, the range hood is now a very popular household appliance, which can effectively remove the oil fume produced during cooking and keep the environment in the kitchen clean. Existing range hoods are generally provided with several fixed gears on the casing panel, and the wind speed generated by the fan blades of the range hood is manually adjusted, thereby changing the suction force of the range hood on the range hood. This design brings some inconvenience to the user. When both hands of the user are occupied, the wind speed cannot be switched in time. At the same time, the user only makes limited adjustments based on subjective feelings. The fixed wind speed may not be able to clean the oil fume; and the fixed wind speed used when the oil fume concentration is small may be too high and cause power waste. In order to achieve the purpose of automatically adjusting the suction force of the range hood, the Chinese patent "A Magnetic Suspension Drum Rotor Type Full-Automatic Range Hood (ZL03206223.0)" provides a technical solution, which is equipped with physical receptors and chemical receptors. The sensor senses the rising speed of the hot air to drive the rotation of the magnetic separation rotor, and transmits the signal to the microcomputer control system to make it turn on the motor switch. If the rising air flow exceeds a certain amount, the high-speed rotation switch can be turned on; and the chemical sensor is a gas concentration sensor. Sensitive to the gas concentration, when the gas concentration reaches or exceeds a certain value, it will feel and generate an electrical signal to the microcomputer controller, and turn on the switch for pumping. In this solution, the physical sensor senses the speed of the hot air flow, and the chemical receptor senses the gas concentration, not the concentration of the oil fume itself. Therefore, there is no range hood that automatically adjusts the draft according to the oil smoke concentration in the prior art. .

Utility model content

The purpose of the utility model is to provide an intelligent range hood that can automatically adjust the exhaust speed of the range hood according to the concentration of oil fumes, thereby automatically adjusting the suction force of the range hood.

The technical scheme of the utility model is: a range hood that automatically adjusts the exhaust speed according to the concentration of oil fume, including a range hood host, an oil fume detection and control device, the oil fume detection and control device is installed on the range hood host, and the oil fume detection and control device includes A photoelectric detection unit and a control circuit, the range fume host at least includes an exhaust device; the photoelectric detection unit is connected to the control circuit, and the control circuit is connected to the exhaust device. The photoelectric detection unit uses the photoelectric effect to detect the concentration of oil fume, and outputs the signal of oil fume concentration to the control circuit. The purpose of automatically adjusting the draw force.

The photoelectric detection unit at least includes a light emitter and a photodetector. There is a space between the light emitter and the photodetector, and gas, liquid droplets, dust, and smoke from the surrounding environment can enter the space. The light transmitter emits a light beam of a certain intensity, and the light beam passes through the oil fume to reach the photodetector. Due to the absorption and reflection of the light beam by the oil fume, the change of the optical signal intensity received by the photodetector corresponds to the change of the oil smoke concentration. When the oil smoke concentration When the light is low or there is no oil smoke, the attenuation of the light beam is small or even no attenuation, and the light signal detected by the photodetector is strong; otherwise, the light signal of the photodetector is weak, and the photodetector works according to the principle of photoelectric effect. A device that converts the detected light intensity signal into an electrical signal. The positions of the light emitter and the photodetector are preferably installed on both sides of the ventilation device, and the photosensitive surface of the light detector faces the light emitter, so as to ensure the accuracy of detection.

The light beam generated by the light emitter is spectrally matched to the light detector. The frequency of the light used can be selected within a wide range, such as infrared light of a certain frequency, visible light of a certain color, or ultraviolet light of a certain frequency. It is only required that the light source and the photodetector must match. For example, if the infrared band is used, then the light source should use an infrared lamp, and the photodetector should use an infrared detector. Other bands are similar.

Optical transmitters can be continuous output or pulsed output optical transmitters. That is to say, the light emitted by the light transmitter can be output continuously or in pulse form. If pulse output is used, the output frequency should not be too low, otherwise it may affect the speed of wind speed regulation.

The photoelectric detection unit may also include an amplifying circuit, one end of the amplifying circuit is connected to the photodetector, and the other end is connected to the control circuit. The amplifying circuit can amplify the electrical signal output by the photodetector, so that the amplitude of the detection signal is compatible with the subsequent control circuit. The amplification circuit can be fully selected in the prior art, but it should match the photodetector, and the amplification factor should also be adjusted to be suitable for the subsequent control circuit.

The control circuit controls the ventilation speed of the ventilation equipment according to the signal strength output by the photoelectric detection unit. When the oil fume concentration is high and the signal strength output by the photoelectric detection unit is weak, the control circuit should increase the current or voltage output to the ventilation equipment. , so that the ventilation speed of the ventilation equipment is accelerated and the suction force is increased; when the concentration of oil fume is small and the signal strength output by the photoelectric detection unit is strong, the control circuit should reduce the current or voltage output to the ventilation equipment, so that the ventilation of the ventilation equipment The speed is reduced and the draw is reduced. Therefore, the control circuit should maintain a monotone decreasing function relationship between the operating power of the ventilation device and the output value of the photoelectric detection unit.

Described monotone decreasing function relationship has many types to choose from, but adopting the form of P=b-af(v) is a better choice, and P is the operating power of exhaust fan in the formula, and v is the output of photoelectric detection unit Value, a and b are positive constant coefficients, f(v) represents a monotonically increasing function about v; wherein the representative function form of f(v) is: f(v)=v or f(v)=lnv. The initial values of a and b are determined by the maximum and minimum output values of the photoelectric detection unit and the rated power of the ventilation equipment. There are many solutions in the prior art for the control circuit to realize the above-mentioned monotonically decreasing function relationship, which can be selected according to the actual situation.

The above-mentioned exhaust equipment may be a motor-driven exhaust fan or an exhaust fan.

In order to make the range hood more convenient to use, the control circuit may also include a manual adjustment device, the manual adjustment device includes at least two adjustment devices to adjust the monotone decreasing function relation P=b-af(v) The size of the constant coefficients a and b in is used to change the current or voltage intensity input to the ventilation equipment to obtain the ventilation speed required by the user. For example, the user feels that the ventilation speed is normal when the concentration of oil fume is low, but the ventilation speed is low when the concentration of oil fume is high, it can be corrected by appropriately reducing a and/or increasing b; When the oil fume concentration is low, the ventilation speed is normal, but when the concentration of oil fume is low, the ventilation speed is too high, which can be corrected by appropriately increasing a and/or reducing b; the user feels that the ventilation speed is low when the concentration of oil fume is low or high , it can be corrected by increasing b; if the user feels that the exhaust speed is high when the oil fume concentration is low or high, it can be corrected by decreasing b.

The cooker hood of the utility model can use the principle of attenuation of light intensity caused by the absorption and reflection effect of lampblack on light by adding a photoelectric detection unit and a control circuit on the basis of no major change in the structure of the existing range hood. The photoelectric detection method measures the oil fume concentration, and converts the change of the oil fume concentration into an electrical signal and outputs it to the control circuit. A manual adjustment device can be added, and the user can choose to manually adjust the exhaust speed, which has the advantages of saving electricity and labor, high oil fume removal efficiency, and low cost.

Description of drawings

Fig. 1 is the structural representation of embodiment 1 of the present utility model;

Fig. 2 is a structural schematic diagram of Embodiment 2 of the present utility model.

Detailed ways

Example 1

A range hood capable of automatically adjusting the ventilation speed of the range hood according to the density of the range hood, comprising a range hood main unit 1, and an oil fume detection and control device, the oil fume detection and control device being installed on the range hood main unit 1, the oil fume detection and control device including a photoelectric detection Unit 2 and control circuit 3 , range hood main unit 1 at least includes a motor-driven exhaust fan 11 ; photoelectric detection unit 2 is connected to control circuit 3 , and control circuit 3 is connected to exhaust fan 11 .

Wherein the photodetection unit 2 includes a light emitter 21, a photodetector 22, and an amplifying circuit 23 whose magnification is matched with the photodetector 22, and there is a space 4 between the light emitter 21 and the photodetector 22, through which oil smoke 5 passes. The space 4 reaches the exhaust fan 11, and the light beam A produced by the light emitter 21 matches the photodetector 22 in spectral characteristics; the photodetector 22 is connected with the amplifier circuit 23, and the light beam A produced by the light emitter 21 passes through the smoke 5 Reaching the photodetector 22, the photodetector 22 converts the light intensity into an electrical signal according to the photoelectric effect, and then amplifies it by the amplifying circuit 23 to obtain the output value v of the photodetection unit 2.

The control circuit 3 should keep the operating power P of the exhaust fan 11 and the output value v of the photoelectric detection unit 2 maintaining a monotone decreasing function relationship P=b-av or P=b-alnv, and a and b are positive constant coefficients.

Example 2

Embodiment 2 has basically the same structure as Embodiment 1, except that a manual adjustment device 6 is added to the control circuit 3 , and the manual adjustment device 6 and other components 7 of the control circuit together form a new control circuit 3 .

The manual adjustment device 6 includes at least two adjustment devices, one of which adjusts the constant coefficient a, and the other adjusts the constant coefficient b, and the user can adjust the suction speed of the exhaust fan 11 as required.

The above embodiments are for describing the utility model in more detail, but the protection scope of the utility model is not limited thereto.

Claims (4)

1. A range hood that automatically adjusts the exhaust speed according to the concentration of oil fume, comprising a range hood host, characterized in that it also includes an oil fume detection and control device, the oil fume detection and control device is installed on the range hood host, and the oil fume detection and control device includes a photoelectric The detection unit and the control circuit, the range fume host at least includes an exhaust device; the photoelectric detection unit is connected to the control circuit, and the control circuit is connected to the exhaust device. 2. The range hood according to claim 1, characterized in that the photoelectric detection unit at least includes a light emitter and a photodetector, there is a space between the light emitter and the photodetector, and the gas and liquid from the surrounding environment Drops and dust, fumes can enter the space. 3. The range hood according to claim 2, wherein the photoelectric detection unit further comprises an amplifier circuit, one end of the amplifier circuit is connected to the photodetector, and the other end is connected to the control circuit. 4. The range hood according to any one of claims 1 to 3, characterized in that the control circuit further includes a manual adjustment device.

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