JPH04190815A - On-vehicle air purifier - Google Patents

Abstract

PURPOSE:To reduce an exhaust sound by eliminating a sound before the sound is emitted from an exhaust port by arranging a distributing body having a large number of exhaust passages different in length in the exhaust cylinder provided on the emitting side of a casing. CONSTITUTION:An impeller 26 is connected to the motor 25 provided in a main body 27. A suction cylinder 29 is provided to the suction part of a casing 24 having the impeller 26 built therein and guiding air and an exhaust cylinder 23 is provided on the emitting side of the casing 24. A distributing body 22 having a large number of exhaust passages 31 different in length is arranged in the exhaust cylinder 23. As a result, a sound is eliminated before emitted from the exhaust port to make it possible to reduce an exhaust sound.

Description

[Detailed description of the invention] Industrial applications TECHNICAL FIELD The present invention relates to a vehicle-mounted air cleaner equipped with a noise reduction function.

BACKGROUND OF THE INVENTION In recent years, air purifiers have been used to improve the indoor environment of automobiles.

As shown in FIG. 5, a conventional air purifier for a vehicle of this type has a main body that includes an intake port 1 and an exhaust port 2 in a tray (not shown) inside the vehicle, and an impeller 7 in a casing 5. 4 in the trunk, and the main body 4 and the intake port 1.
The exhaust port 2 was configured to be connected by an intake pipe 8 and an exhaust pipe 3.

With the above configuration, air taken from inside the vehicle through the intake port 1 passes through the intake pipe 8, passes through the filter 6, is purified, and then passes through the casing 5 containing the impeller 7 attached to the motor (not shown). Exhaust port 2 through exhaust pipe 3
It is designed to be sent into the car from the inside.

Problems to be Solved by the Invention In such conventional car air purifiers, a high air volume is required to quickly clean the air in the bad environment inside the car, and in this case, the impeller 7 is rotated at high speed. The most effective method is to drive at low speeds, but the exhaust noise also increases proportionally. In particular, in-vehicle air purifiers have intake and exhaust ports in the rear tray due to their structure, and when a person sits in the back seat, the sound can be heard directly to the ears, which can cause air disturbance from the in-vehicle air purifier. The present invention solves the above-mentioned problems, such as the low-frequency sound generated by the impeller, the NZ sound generated when the impeller cuts the air, and the high-frequency noise such as the high frequency. To provide an on-vehicle air cleaner capable of reducing exhaust noise by muffling the noise before it comes out from an exhaust port.

Means for Solving the Problems In order to achieve the above objectives, the air purifier of the present invention includes a main body, a motor provided in the main body, an impeller connected to the motor, and an air purifier that accommodates the impeller. A casing that guides the air, an intake pipe provided at the suction part of the casing, and an exhaust pipe provided at the discharge side of the casing, and a flow regulator having a large number of exhaust passages of different lengths is arranged in the exhaust pipe. The structure is as follows.

Effect In the above-mentioned configuration, the exhaust flow discharged from the casing is rectified in response to sounds in the low frequency range by passing through a rectifier whose cross section is divided into a grid pattern and provided with a large number of exhaust passages. The sound is muted. In addition, N noise and N noise caused by the motor
For sounds in a high frequency range such as Z sound, the length of the exhaust passage of the fluid regulator is set to the length of that wavelength and 1/2 wavelength, or 1/2 wavelength and 1.4 wavelengths. The sound is muted by mutual interference. This is because the sound emitted from the casing is in the same phase until it passes through the exhaust passage of the fluid regulator, but for sounds in a certain high frequency range, the sound that has passed through the exhaust passage of the same length as that wavelength and the sound that has a wavelength of 172 wavelengths. If the sound passes through an exhaust passage of the same length, the phase will be shifted by 00 degrees. The sounds exiting the exhaust passages spread concentrically inside the exhaust pipe from the exhaust passage openings due to diffraction, and are muted because they interfere and cancel each other out.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to FIGS. 1 and 2. As shown in the figure, an intake port 30 and an exhaust port 21 are installed in a car tray (not shown).
Further, a main body 27 in which an impeller 26 directly connected to a motor 25 is provided in a casing 24 is arranged in the trunk, and the main body 27 and an intake port 30. The exhaust port 21 is connected to the intake cylinder 29. They are connected by an exhaust pipe 23, and within the exhaust pipe, the flat surface of the rectifier pair 22 is placed on the casing 24 side, and the obliquely cut side is installed on the exhaust port 21 side. Regarding the configuration of the flow regulator 22, its cross section has a honeycomb structure in addition to the lattice shape in order to reduce pressure loss. and 172 wavelengths and 1/'2 wavelength and 1/'4
The exhaust passage 31 is set to the length of the wavelength. The rectifying fluid 22 has a cross section obliquely inclined toward the exhaust passage exit side, thereby continuously changing the length of the exhaust passage 31 through which the airflow passes, and is configured to be able to handle a wide range of frequencies.

Moreover, the method of installing the fluid regulator 22 is such that the flat lower surface of the fluid regulator 22 partially enters into the casing 24. Note that the shape of the outlet of the exhaust passage 31 of the fluid regulating fluid 22 may be any shape as long as the length of the exhaust passage 31 is changed by slanting the discharge side as shown in FIGS. 3 and 4.

To explain the operation in the above configuration, as the impeller 26 attached to the motor 25 rotates, air inside the vehicle is taken in from the intake port 30 and passes through the intake pipe 29.
A large number of exhaust passages 3 of the fluid regulator 22 are cleaned by the filter 28, passed through the casing 24, and installed in the exhaust pipe.
1, and the sounds exiting the exhaust passage 31 spread concentrically inside the exhaust pipe 23 from the exit of the exhaust passage due to a diffraction phenomenon, cause interference, cancel each other out, and are muffled. It is circulated throughout the car. By installing the rectifier 22 in the exhaust stack 23, the exhaust flow can be rectified in response to sounds in the low frequency range by passing through the rectifier pair 22 in which a large number of exhaust passages 31 are provided in a lattice shape. The sound is muted. Furthermore, for high-frequency sounds such as NZ sounds caused by motors, if the frequency is 20001-1x, the length of the exhaust passage is set to the wavelength (1x).
9C) and 1/2 wavelength (9.5cm) or 1/2 wavelength (9.5c+++) and 1/4 wavelength (4.75cm), the NZ sound will be emitted from the exhaust passage 31 of the rectifying fluid 22. Until they pass through, they are in the same phase, but when the sound passes through the 19cm exhaust passage 31 and the 9.5cm exhaust passage 31, or the 9.5cm exhaust passage 31 and the 4.75c+n exhaust passage 31, the phase shifts by 90 degrees. Become. The sounds exiting the exhaust passage 31 spread concentrically inside the exhaust pipe 23 from the exit of the exhaust passage due to the diffraction phenomenon, and are muted because they interfere and cancel each other out. In addition, by slanting the cross section on the exhaust passage exit side, the length of the exhaust passage 31 through which the airflow passes is continuously changed, so a similar effect can be obtained in the frequency range around 2000 Hz. Become.

Effects of the Invention As is clear from the above description of the embodiments, the air purifier of the present invention includes a main body, a motor provided in the main body, an impeller connected to the motor, and a wind impeller that is housed in the air purifier. The exhaust pipe includes a casing, an intake pipe provided at the suction part of the casing, and an exhaust pipe provided at the discharge side of the casing, and a flow regulator having a large number of exhaust passages of different lengths is arranged in the exhaust pipe. By using a structure that consists of a slit-shaped flow rectifier, the exhaust flow is rectified in the low frequency range that occurs when the air is turbulent, and when the impeller cuts the air, the exhaust flow is rectified. High frequency ranges such as NZ sound and its high frequencies can be efficiently muffled by selecting the length of the rectifier pipe passage according to the frequency to be muffled due to phase interference caused by the sound diffraction phenomenon. It can exhibit a silencing effect on the entire frequency range of exhaust noise emitted from the exhaust port.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a car air cleaner showing an embodiment of the present invention, Figs. 2, 3, and 4 are perspective views of a flow regulator, and Fig. 5 is a cross-sectional view of a conventional car air cleaner. FIG. 22...Fluid regulator, 23...Exhaust pipe, 2
4... Casing, 25... Motor,
26... Impeller, 27... Body, 2
9...Intake cylinder, 32...Exhaust port. Name of agent: Patent attorney Haruaki Ogata and 2 others ZZ --ＥL
23-2 Darkness 24- Casing-Motor 26-Inmara 27-Full intake zq-Intake accommodation Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] A main body, a motor provided in the main body, an impeller connected to the motor, a casing that houses the impeller and guides wind, an intake cylinder provided in the suction part of the casing, and an intake cylinder provided on the discharge side of the casing. A vehicle-mounted air cleaner comprising an exhaust pipe, and a flow regulator having a large number of exhaust passages of different lengths disposed within the exhaust pipe.