CN102697277A - Noise-reducing and energy-saving device for hair dryer - Google Patents

Abstract

The invention is a noise reduction and energy saving device for a hair dryer. It includes an outer layer (1) and an inner layer (2). The outer layer (1) is a non-porous sound-absorbing metal plate, and the inner layer (2) is a sound-absorbing metal plate with several through holes (21). The outer layer (1) and the inner layer (2) are arranged in parallel, and the two parallel A resonant cavity is formed between the sound-absorbing metal plates. The air in the cavity is elastic, which is equivalent to a spring. The air column in the aperture reciprocates like a piston. Due to the damping effect of the neck wall on the air, part of the sound energy is converted into heat energy. In the present invention, when the frequency of the incident sound wave is consistent with the natural frequency of the resonant cavity, the resonance phenomenon will occur. At this time, the air column in the aperture has the largest movement range on the aperture wall of the small hole, and the sound energy can be maximized in this case. converted into heat energy. To achieve a certain effect of noise reduction and energy saving. The invention is balanced in cost and effect, can have the same sound-absorbing effect under the condition of lower cost, and has simple structure, convenient use, low cost and good economic benefit.

Description

Noise reduction and energy saving device for hair dryer

technical field

The invention relates to a noise reduction and energy-saving device for a hair dryer, which belongs to the transformation technology of the energy-saving device used for noise reduction of the hair dryer.

Background technique

Hair dryers are widely used in households, hairdressing and beauty, etc., but the noise generated by hair dryers has always troubled people. The hair dryers on the market reduce their noise from the design of the cavity and the selection of materials, but considering the noise reduction effect and cost performance, it is difficult to achieve the ideal noise reduction effect.

Contents of the invention

The purpose of the present invention is to consider the above problems and provide a noise reduction and energy saving device for a hair dryer that can achieve a balance between cost and effect, and can also have a better noise reduction effect at a lower cost. The invention has the advantages of simple structure, convenient use, low cost and good economic benefit.

The technical solution of the present invention is: the hair dryer noise reduction and energy-saving device of the present invention includes an outer layer and an inner layer, the outer layer is a non-porous sound-absorbing metal plate, and the inner layer is a sound-absorbing metal plate provided with several through holes, The outer layer and the inner layer are arranged in parallel, and a resonant cavity is formed between the two parallel sound-absorbing metal plates.

。 The distance between the through holes in the above-mentioned inner layer is b , the hole diameter is d , the thickness of the inner layer is t , the distance between the outer layer and the inner layer is D , the resonant frequency f ₀ and the anechoic frequency band f ₁ — The relationship between f ₂ is:

.

The shape of the outer layer and the inner layer corresponds to the shape of the hair dryer shell, and the outer layer and the inner layer are set on the shell of the hair dryer, or the outer layer and the inner layer are directly the shell of the hair dryer.

The outer layer and the inner layer are combined to form a truncated cone, and the outer layer and the inner layer are set on the casing of the hair dryer.

When the noise frequency band of the incident sound wave is 1-5.5 kHz; when the center frequency f ₀ =3114.5Hz, the above hole distance b = 2.57mm; cavity depth D = 1.19cm; plate thickness t = 0.20mm; aperture d = 0.50 mm.

Because the present invention adopts the structure of the noise reduction device added to the shell of the hair dryer, the internal structure of the noise reduction device is divided into inner and outer layers. A resonant cavity with a certain natural frequency is formed between two parallel sound-absorbing plates. The air in the cavity is elastic, which is equivalent to a spring. The air column in the aperture reciprocates like a piston. Due to the damping effect of the neck wall on the air, part of the sound energy is converted into heat energy. In the present invention, when the frequency of the incident sound wave is consistent with the natural frequency of the resonant cavity, the resonance phenomenon will occur. At this time, the air column in the aperture has the largest movement range on the aperture wall of the small hole, and the sound energy can be maximized in this case. The ground is converted into heat energy to achieve a certain effect of noise reduction. For the HP905 hair dryer, in its frequency band of 1.0-5.5 kHz, the noise reduction range is about 20-25dB. The present invention is balanced in cost and effect, so that it can have the same noise reduction effect at a lower cost, and has the characteristics of simple structure, convenient use, low cost, and good economic benefits. The present invention is a design Ingenious, excellent performance, convenient and practical noise reduction and energy saving device for hair dryer.

Description of drawings

Fig. 1 is a schematic structural view of installing the device of the present invention on a hair dryer.

Fig. 2 is an internal structure diagram of the muffler of the present invention.

Fig. 3 is a cross-section of the internal structure of the present invention.

Fig. 4 is a perspective view of the present invention in the form of a truncated cone.

Detailed ways

Example:

Schematic diagrams of the present invention are shown in Figures 1, 2, 3, and 4. The hair dryer noise reduction and energy-saving device of the present invention includes an outer layer 1 and an inner layer 2. The outer layer 1 is a non-porous sound-absorbing metal plate, and the inner layer Layer 2 is a sound-absorbing metal plate provided with several through holes 21, the outer layer 1 and the inner layer 2 are arranged in parallel, and a resonant cavity is formed between the two parallel sound-absorbing metal plates.

。本发明的消声频率范围为500～6000Hz，即入射声波的噪声频带范围为500～6000Hz，间距D =0.5～1.5cm ，孔距b=1～3.5mm ，孔径d= 0.15～0.5mm，内层（2）的板厚t= 0.20～0.7mm。本实施例中，当入射声波的噪声频带为1～5.5 kHz；共振频率f ₀=3114.5Hz时，上述孔距b = 2.5761mm；空腔深度D =1.19cm；板厚t= 0.20mm；孔径d = 0.5mm。   The hole distance of the through holes 21 set in the above-mentioned inner layer 2 is b , the hole diameter is d , the plate thickness of the inner layer 2 is t , the distance between the outer layer 1 and the inner layer 2 is D , and the resonance frequency f ₀ is related to the disappearance The relationship between the audio frequency bands f ₁ — f ₂ is:

. The noise reduction frequency range of the present invention is 500-6000 Hz, that is, the noise frequency range of the incident sound wave is 500-6000 Hz, the distance D=0.5-1.5 cm, the hole distance b=1-3.5 mm, the hole diameter d=0.15-0.5 mm, and the inner The plate thickness t=0.20～0.7mm of layer (2). In this embodiment, when the noise frequency band of the incident sound wave is 1-5.5 kHz; when the resonance frequency f ₀ =3114.5Hz, the above-mentioned hole distance b = 2.5761mm; cavity depth D = 1.19cm; plate thickness t = 0.20mm; aperture d = 0.5mm.

The shape of the outer layer 1 and the inner layer 2 corresponds to the shape of the hair dryer shell, and the outer layer 1 and the inner layer 2 are set on the shell of the hair dryer, or the outer layer 1 and the inner layer 2 are directly the shell of the hair dryer.

The outer layer 1 and the inner layer 2 are combined into a truncated circular shape, and the outer layer 1 and the inner layer 2 are set on the casing of the hair dryer.

The present invention can be made into a structure similar in shape to the shell of the hair dryer, and is directly set on the shell of the hair dryer. The two sound-absorbing plates of the present invention form a resonance cavity with a certain natural frequency. When the incident noise sound wave of the hair dryer and the resonance cavity When the natural frequency is close to the same, due to resonance, the elastic air column formed between the through hole 21 set in the inner layer 2 and the outer layer 1 is like a piston, making the most violent back and forth at the through hole 21 set in the inner layer 2. The reciprocating motion makes the neck wall on the through hole 21 play the largest damping effect on the air column, thereby converting the sound energy into heat energy to the maximum extent, which not only makes reasonable use of energy, but also effectively reduces the noise of the hair dryer, which is energy-saving. Dual effects of environmental protection and noise reduction. For the HP905 hair dryer, in its frequency band of 1.0-5.5kHz, the noise reduction range is about 20-25dB.

Claims (5)

1. A noise-reduction and energy-saving device for a hair dryer, characterized in that it includes an outer layer (1) and an inner layer (2), the outer layer (1) is a non-porous sound-absorbing metal plate, and the inner layer (2) It is a sound-absorbing metal plate provided with several through holes (21), the outer layer (1) and the inner layer (2) are arranged in parallel, and a resonant cavity is formed between the two parallel sound-absorbing metal plates. 2. The noise reduction and energy-saving device for hair dryer according to claim 1, characterized in that the hole distance of the through holes (21) in the inner layer (2) is b , the hole diameter is d , and the inner layer ( 2) The plate thickness is t , the distance between the outer layer (1) and the inner layer (2) is D , the relationship between the resonant frequency f ₀ of the resonant cavity and the anechoic frequency band f ₁ - f ₂ is :

. 3. The noise reduction and energy-saving device for hair dryer according to claim 1, characterized in that the shapes of the outer layer (1) and the inner layer (2) correspond to the shape of the hair dryer shell, and the outer layer (1) and the inner layer (2) are set on the shell of the hair dryer, or the outer layer (1) and the inner layer (2) are directly the shell of the hair dryer. 4. The noise reduction and energy saving device for hair dryer according to claim 1, characterized in that the outer layer (1) and the inner layer (2) are combined into a truncated circular shape, and the outer layer (1) and the inner layer (2) Set on the casing of the hair dryer. 5. The noise reduction and energy-saving device for hair dryer according to claim 1, characterized in that when the noise frequency band of the incident sound wave is 1-5.5 kHz; when the resonance frequency f ₀ =3114.5 Hz, the above-mentioned hole distance b = 2.57 mm ; Cavity depth D = 1.19cm; Plate thickness t = 0.20mm; Hole diameter d = 0.50 mm.

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