KR-20260063672-A - Duct type active noise control device

Abstract

The present invention relates to a duct-type active noise control device capable of reducing noise emitted into the air by using a duct to induce noise to be emitted to the outside in range hoods, heating and cooling ventilation equipment, etc., and by using active noise control technology to eliminate noise while the noise passes through the duct. To this end, the duct-type active noise control device according to the present invention includes a reference microphone for collecting a noise signal generated from a motor fan in a range hood, heating and cooling ventilation equipment, etc., a noise control signal generation unit for generating a noise control signal having the same magnitude as the noise signal and a 180-degree phase difference and outputting it to a speaker, an error microphone for collecting a residual noise signal remaining after the noise signal and the noise control signal are superimposed, and a control unit for controlling the noise control signal generation unit to continuously generate a noise control signal until the magnitude of the residual noise signal becomes less than or equal to a preset value.

Inventors

• 민훈

Assignees

• 민훈

Dates

Publication Date

20260507

Application Date

20241030

Claims (6)

1. A duct through which an analog noise signal generated from a range hood or a motor fan of a heating, cooling, and ventilation system propagates, and A reference microphone installed at the inlet of the duct above, which collects the analog noise signal and outputs it as an electrical signal, and A first signal processing unit that amplifies and digitally converts the electrical signal of the above-mentioned reference microphone to output a digital noise signal, and A noise control signal generation unit that generates a digital noise control signal having the same magnitude as the digital noise signal and a 180-degree phase difference, and A second signal processing unit that outputs an electrical signal by converting and amplifying the digital noise control signal of the noise control signal generation unit above into analog, and A speaker installed at the duct outlet and outputting the electrical signal of the second signal processing unit as an analog noise control signal, and An error microphone installed at the duct outlet, which collects the remaining analog residual noise signal after the analog noise signal and the analog noise control signal overlap and outputs it as an electrical signal, and A third signal processing unit that amplifies and digitally converts the electrical signal of the above error microphone to output a digital residual noise signal, and A duct-type active noise control device comprising a control unit that controls the noise control signal generator to continuously generate a digital noise control signal corresponding to the digital residual noise signal until the magnitude of the digital residual noise signal becomes less than or equal to a preset value.
2. A reference microphone for collecting noise signals generated from a range hood or a motor fan of a heating, cooling, and ventilation system, and A noise control signal generation unit that generates a noise control signal having the same magnitude as the above noise signal and a 180-degree phase difference, and outputs it to a speaker; An error microphone that collects the residual noise signal remaining after the above noise signal and the above noise control signal are superimposed, and A duct-type active noise control device comprising a control unit that controls the noise control signal generator to continuously generate a noise control signal until the magnitude of the residual noise signal becomes less than or equal to a preset value.
3. A duct composed of an outer tube and an inner tube, with sound-absorbing material filled between the outer tube and the inner tube, through which a noise signal travels along the inside of the inner tube, and A reference microphone installed on the duct inlet side to collect noise signals generated from a range hood or a motor fan of a heating, cooling, and ventilation system, and A speaker installed in a first noise control area on the duct outlet side and outputting a noise control signal to eliminate a noise signal, and A duct-type active noise control device including an error microphone installed in a first noise control area on the duct outlet side to collect residual noise signals remaining after the noise signal and the noise control signal are superimposed.
4. A duct composed of an outer tube and an inner tube, with sound-absorbing material filled between the outer tube and the inner tube, through which a noise signal travels along the inside of the inner tube, and A microphone module installed inside the inner tube and having its interior filled with sound-absorbing material, and A reference microphone installed inside the microphone module located at the duct inlet side to collect noise signals generated from a range hood or a motor fan of a heating and cooling ventilation system, and A speaker installed in the noise control area on the duct outlet side and outputting a noise control signal to eliminate a noise signal, and A duct-type active noise control device comprising an error microphone installed inside the microphone module located in the noise control area on the duct outlet side, which collects the residual noise signal remaining after the noise signal and the noise control signal are superimposed.
5. A duct composed of an outer tube and an inner tube, with sound-absorbing material filled between the outer tube and the inner tube, through which a noise signal travels along the inside of the inner tube, and A first reference microphone installed on the duct inlet side to collect noise signals generated from a range hood or a motor fan of a heating, cooling, and ventilation system, and A first speaker installed in a first noise control area between the duct inlet and the duct outlet and outputting a first noise control signal for removing a noise signal, and A first error microphone installed in a first noise control area between the duct inlet and the duct outlet, which collects the first residual noise signal remaining after the noise signal and the first noise control signal overlap. A second reference microphone installed after the first noise control area to collect a first residual noise signal, and A second speaker installed in a second noise control area on the duct outlet side and outputting a second noise control signal to remove a first residual noise signal, and A duct-type active noise control device comprising a second error microphone installed in a second noise control area on the duct outlet side, which collects the second residual noise signal remaining after the first residual noise signal and the second noise control signal are superimposed.
6. In any one of paragraphs 3 through 5, A duct-type active noise control device characterized by having a connection formed between the outer duct and the inner duct, and a resonator installed on the outer duct along the connection.

Description

Duct type active noise control device The present invention relates to a duct-type active noise control device capable of reducing noise emitted into the air through a duct by using a duct to induce noise emitted from a range hood, heating and cooling ventilation equipment, etc., to be emitted to the outside, and by using active noise control technology to eliminate the noise while it passes through the duct. The concentration of fine dust generated when grilling or stir-frying meat or fish in the kitchen generally exceeds environmental standards by more than 70 times. High concentrations of fine dust generated in kitchens are the leading cause of lung cancer among non-smoking women in Korea. However, if you install a range hood in the kitchen and operate it while cooking, the concentration of fine dust can be drastically reduced to about one-seventh. As such, range hoods are essential equipment for reducing fine dust generated in the kitchen, but the noise level generated when operating the range hood is 65 to 70 dB, which is inconvenient for daily life, so there is a problem that operating the range hood for a long time is considerably inconvenient due to such noise. FIG. 1 is a drawing showing the structure of a general range hood to which a duct-type active noise control device according to the present invention is applied. FIG. 2 is a schematic block diagram of a duct-type active noise control device according to the present invention. FIG. 3 is a drawing showing the installation of a duct-type active noise control device according to the first embodiment of the present invention. FIG. 4 is a drawing showing the installation of a duct-type active noise control device according to a second embodiment of the present invention. FIG. 5 is a drawing showing the installation of a duct-type active noise control device according to a third embodiment of the present invention. FIG. 6 is a drawing showing the installation of a duct-type active noise control device according to the fourth embodiment of the present invention. The objects, specific advantages, and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments in conjunction with the accompanying drawings. The terms used are defined with consideration of their functions in the present invention, and these may vary depending on the intent or convention of the user or a person skilled in the relevant technical field. Therefore, the definitions of these terms should be based on the content throughout this specification. Figure 1 shows the structure of a range hood to which a duct-type active noise control device according to the present invention is applied. Referring to FIG. 1, the range hood includes a canopy (10) installed above a gas range or induction cooktop to come into direct contact with smoke or fine dust generated during cooking, a first duct (20) connected to the canopy (10), a second duct (30) connected to the first duct (20) to go outside, and a motor fan (40) installed at the connection point between the first duct (20) and the second duct (30) to suck in smoke or fine dust. When the range hood is operated, the motor fan (40) rotates, and smoke or fine dust generated during cooking is sucked in through the first duct (20) connected to the hole in the canopy (10) and discharged to the outside through the second duct (30). At this time, noise is generated due to the rotation of the motor fan (40) and is discharged into the room through the first duct (20). The duct-type active noise control device according to the present invention allows a portion of the noise generated by the rotation of the motor fan (40) to exit to the outside through the second duct (30), while eliminating the noise exiting from the inlet (22) to the outlet (24) of the first duct (20), thereby enabling the overall reduction of the rotational noise of the motor fan (40) released into the air. The duct-type active noise control device according to the present invention combines a passive noise reduction technology that reduces high-frequency noise using the sound absorption characteristics of a sound-absorbing material and an active noise control technology that reduces low-frequency noise using a microphone and a speaker, with a noise signal passing through a duct (20, 30). Figure 2 shows a block diagram of a duct-type active noise control device according to the present invention. Referring to FIG. 2, the duct-type active noise control device includes a reference microphone (101) for collecting a noise signal generated by the rotation of a motor fan (40), a noise control signal generator (303) for generating a noise control signal that has the same magnitude as the noise signal and a 180-degree phase difference, a speaker (305) for outputting the noise control signal, an error microphone (307) for collecting a residual noise signal remaining after the noise signal and the noise control signal are sup