The present invention relates to the technical field of supercharged engines, and particularly, relates to a noise reduction structure of a supercharger.
With increasingly high requirements of customers on vehicle fuel economy and dynamic property, vehicles adopting supercharged engines are developed increasingly fast at present. However, with the use of a supercharged engine, bad noise such as supercharger gas relief noise (when an accelerator is released, a throttle is closed but the supercharger still works, the pressure between the supercharger and the throttle is increased sharply, the high pressure needs to be relieved in order to ensure drivability, and gas relief noise is produced with the relief of the high pressure gas, particularly under the working condition that the accelerator is released urgently), supercharger howling, supercharger surge and the like may be produced, thus influencing the subjective feeling of customers.
Currently, universal methods for solving the problem of supercharger gas relief noise include: 1, enlarging a relief channel in the supercharger; 2, adding silencers to the inlet and outlet of the supercharger; 3, adjusting ECU (Electronic Control Unit) calibration data, and controlling the pressure relief time (to control the pressure value during pressure relief and eliminate the gas relief noise); 4, changing the internal pressure relief manner of the supercharger into an external one (relative to the supercharger), which is realized by a three-way electromagnetic valve (controlled by an ECU and negative pressure of a manifold), a mechanical relief valve (controlled by an electromagnetic valve) and connecting pipelines thereof; and 5, changing the internal pressure relief manner of the supercharger into an external one, which is realized by a relief valve electromagnetic valve, a silencer and a connecting pipeline thereof.
The above five methods eliminate the gas relief noise to a certain extent, but the effect of eliminating the gas relief noise is still poor, and some improvement methods are high in cost, e.g., the method 4.
One aim of the present invention is to provide a noise reduction structure of a supercharger with good effect of eliminating gas relief noise at low cost.
The present invention provides a noise reduction structure of a supercharger, including a relief channel of the supercharger and a silencing assembly, wherein the relief channel is provided with a high pressure pipeline and a low pressure pipeline; the silencing assembly is arranged at a gas circulation position between the high pressure pipeline and the low pressure pipeline, provided with a plurality of vent holes having the diameter of less than 20 mm, and configured in such a way that high pressure gas only enters the low pressure pipeline after passing through the vent holes when the high pressure pipeline is communicated with the low pressure pipeline.
Further, the gas outlet end of the high pressure pipeline is inserted into the low pressure pipeline; the silencing assembly is sleeved at the gas outlet end of the high pressure pipeline, and is connected with the high pressure pipeline in a sealed manner.
Further, the silencing assembly is of a tubular structure, and the plurality of vent holes are formed in the tubular wall of the silencing assembly.
Further, the diameter of the vent holes ranges from 1 mm to 2 mm.
Further, the plurality of vent holes are uniformly distributed along the tubular wall of the silencing assembly, and the distance between every two vent holes is 6 to 7 times the diameter of the vent holes.
Further, the noise reduction structure also includes: a relief valve, arranged at the connector between the high pressure pipeline and the low pressure pipeline which are isolated or communicated by controlling the opening and closing of the relief valve.
Further, a valve seat of the relief valve is integrated on the supercharger, the inner cavity of the valve seat forms a part of the low pressure pipeline, and the gas outlet end of the high pressure pipeline is arranged in the inner cavity of the valve seat; a gate of the relief valve presses against the gas outlet end of the high pressure pipeline, and the gate closes the gas outlet end of the high pressure pipeline when the relief valve is closed; and when the relief valve is opened, a gas outlet channel is formed between the gate and the gas outlet end of the high pressure pipeline.
Further, the silencing assembly is arranged in the inner cavity of the valve seat and sleeved outside the gas outlet end of the high pressure pipeline, one end of the silencing assembly is connected with the inner wall of the inner cavity of the valve seat in a sealed manner, and the other end of the silencing assembly is connected with the outer wall of the high pressure pipeline in a sealed manner.
Further, the silencing assembly is a silencing plate with vent holes, the silencing plate is arranged at the gas outlet end of the high pressure pipeline, and the circumference of the silencing plate is connected to the inner wall of the high pressure pipeline in a sealed manner.
The silencing principle of the silencing assembly is established on the basis that air can reduce audible jet noise when passing through small-diameter vent holes; when gas in the high pressure pipeline enters the low pressure pipeline, the gas can only enter the low pressure pipeline from the plurality of vent holes having the diameter of less than 20 mm, and the jet noise is reduced when the gas passes through the vent holes, so that the voiced frequency of gas relief noise in the pressure relief process is reduced, the frequency of the gas relief noise is turned to an ear-insensitive range, and the effect of reducing noise is thus achieved. The silencing assembly is arranged in the relief channel of the supercharger and is easy to install and add without excessive complex structures, and compared with the silencer in the prior art, unexpected silencing effect can be achieved only by the structural assembly with a plurality of vent holes having the diameter of less than 20 mm, and the cost is lower.
Described below are specific embodiments of the present invention, the technical solution of the present invention will be further described in combination with the specific embodiments and the accompanying drawings, but the present invention is not limited to these embodiments.
A noise reduction structure of a supercharger in this embodiment is used in the field of automobiles. For a relief structure of a supercharger in the prior art, reference may be made to
The silencing principle of the silencing assembly 20 in this embodiment is established on the basis that air can reduce audible jet noise when passing through small-diameter vent holes. In the pressure relief process, high pressure gas enters the low pressure pipeline from the high pressure pipeline 11, the gas can only enter the low pressure pipeline 12 from the plurality of vent holes 21 having the diameter of less than 20 mm, and the jet noise is reduced when the gas passes through the vent holes 21, so that the voiced frequency of gas relief noise in the pressure relief process is reduced, the frequency of the gas relief noise is turned to an ear-insensitive range, and the effect of reducing noise is thus achieved. The silencing assembly in this embodiment is arranged in the relief channel of the supercharger and is easy to install and add without excessive complex structures, and compared with the silencer in the prior art, an unexpected silencing effect can be achieved only by the structural assembly with a plurality of vent holes having the diameter of less than 20 mm, and the cost is lower.
As shown in
More specifically, a valve seat of the relief valve 30 is integrated on the supercharger 40, the inner cavity 31 of the valve seat forms a part of the low pressure pipeline 12, and the gas outlet end 13 of the high pressure pipeline 11 is arranged in the inner cavity 31 of the valve seat. The silencing assembly 20 is arranged in the inner cavity 31 of the valve seat and sleeved outside the gas outlet end 13 of the high pressure pipeline 11, one end of the silencing assembly 20 is connected with the inner wall of the inner cavity 31 of the valve seat in a sealed manner, and the other end of the silencing assembly 20 is connected with the outer wall of the high pressure pipeline 11 in a sealed manner.
The gate 32 of the relief valve 30 presses against the gas outlet end 13 of the high pressure pipeline 11, and the gate 32 closes the gas outlet end 13 of the high pressure pipeline 11 when the relief valve 30 is closed; and when the relief valve 30 is opened, a gas outlet channel is formed between the gate 32 and the gas outlet end 13 of the high pressure pipeline 11, and the silencing assembly 20 is just arranged on the gas outlet channel, so that circulated gas is circulated from the vent holes to the low pressure pipeline 12 to complete silencing.
The gas outlet end 13 of the high pressure pipeline 11 is inserted into the low pressure pipeline 12. The silencing assembly 20 is sleeved at the gas outlet end 13 of the high pressure pipeline 11, and is connected with the high pressure pipeline 11 in a sealed manner.
It can be seen according to
Besides, the gate 32 of the relief valve 30 penetrates through the inner side of the silencing assembly 20 and presses against the gas outlet end 13 of the high pressure pipeline 11, and one end, matched with the gate 32, of the silencing assembly 20 is connected with the relief valve 30 in a sealed manner and simultaneously connected with the side wall of the inner cavity 31 of the valve seat in a sealed manner too, so that gas in the high pressure pipeline 11 can only flow to the low pressure pipeline 12 via the vent holes of the silencing assembly 20, and noise is reduced in this process.
Further, preferably, the silencing assembly 20 is of a tubular structure, the plurality of vent holes 21 are formed in the tubular wall of the silencing assembly 20, and the plurality of vent holes 21 are uniformly distributed along the tubular wall of the silencing assembly 20, referring to the silencing assembly shown in
Under the condition of silencing via the silencing assembly, the diameter of the vent holes 21 can be changed, so that the acoustical power behind each octave band measuring plate is reduced, and the octave band is pushed to a higher ear-insensitive range. When the hole diameter is large (11.8-20.08 mm), about 9 dB can be reduced. When the hole diameter is relatively small, e.g., the diameter of the vent holes 21 is 1-2 mm, each octave band of small-hole noise and A acoustical power can be reduced by about 15 dB; when the diameter of the vent holes is reduced, not only can the acoustical power of noise produced in unit area be reduced, but also the central band of the highest acoustic pressure level can be pushed upwardly to 1 octave band. Thus, if the hole diameter is smaller, the band occupying the principal component is higher; when the central band is over 8000 Hz, human ears are insensitive to noise, so that the subjective feeling of human ears on noise can also be reduced; under equal flow rate, a large hole can be replaced by a lot of small holes, which not only can reduce the A acoustic level, but also can eliminate jet impulsive noise. In the practical manufacturing and using process, the diameter of the vent holes 21 ranges from 1 mm to 2 mm, and when the distance between every two vent holes 21 is 6 to 7 times the diameter of the vent holes 21, the gas passing quantity and silencing effect of the silencing assembly are optimal.
In one embodiment not shown, the silencing assembly 20 is different from the tubular silencing assembly in the above embodiment and is a silencing plate with vent holes 21, the silencing plate is arranged at the gas outlet end 13 of the high pressure pipeline 11, and the circumference of the silencing plate is connected to the inner wall of the high pressure pipeline 11 in a sealed manner. In other embodiments not shown, the diameter and distance of the vent holes 21 of the silencing assembly can be determined according to actual noise reduction needs, or the tubular silencing assembly is replaced by using a netlike object with vent holes, and the size, shape and distance of meshes can be determined according to actual noise reduction needs.
In other embodiments, the relief channel of the supercharger is arranged outside the supercharger, the relief channel is not integrated with the supercharger and is independent from the supercharger, this structure is not the same as the external structure of the above embodiment but is still the one in which the high pressure pipeline is connected with the low pressure pipeline and pressure relief is controlled by a relief valve, and its principle is consistent with the principle of the supercharger integrated with the relief channel. The silencing assembly is arranged at the gas circulation position between the high pressure pipeline and the low pressure pipeline, provided with a plurality of vent holes having the diameter of less than 20 mm, and configured in such a way that high pressure gas only enters the low pressure pipeline after passing through the vent holes when the high pressure pipeline is communicated with the low pressure pipeline, so that this noise reduction structure still can achieve the above technical effects and thus is not redundantly described herein.
The specific embodiments described in the present invention are merely exemplary for the spirit of the present invention. Various modifications or supplements or similar substitutions can be made to the described specific embodiments by those skilled in the art without departing from the spirit of the present invention or exceeding the scope of the appended claims.
Filing Document | Filing Date | Country | Kind |
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PCT/CN2014/092204 | 11/25/2014 | WO | 00 |