CN114763754A - Silencer - Google Patents

Abstract

The invention discloses a silencer which comprises a shell, an inner cylinder and an air inlet pipe. The shell is provided with an outlet end and a closed end which are opposite to each other, and the outlet end is provided with an air outlet. An inner barrel is disposed within the housing and spaced apart from the inner wall of the housing, the inner barrel including an expansion chamber. The air inlet pipe is communicated to the expansion cavity. The space between the side wall of the inner cylinder and the side wall of the shell is a backflow air channel, and the backflow air channel is communicated to the space between the expansion cavity and the outlet end of the shell and the end part of the inner cylinder close to the outlet end. The silencer disclosed by the invention has the advantages of compact structure, light weight, simplicity in maintenance, wide silencing frequency band, excellent silencing performance, good cooling effect, high stability and the like, and has good economic benefits.

Description

a muffler

technical field

The invention relates to the technical field of vibration reduction and noise reduction, in particular to a muffler.

Background technique

Mufflers are mainly divided into three categories according to their structural principles, namely resistive mufflers, resistive mufflers and composite mufflers. Among them, the resistive muffler has a good effect on medium and low frequency noise, but its muffler frequency band is narrow, and the effect on high frequency noise is poor. Resistive mufflers are the opposite. The composite muffler is a combination of resistive and resistive structures to obtain a wide-band noise reduction effect from low frequency to high frequency. However, the design of the muffler should not only meet the requirements of the two main performance indicators of aerodynamic performance and acoustic performance, but also consider the requirements of its structure, material, use environment and installation space.

At present, in addition to reducing exhaust noise, marine internal combustion engines also need to reduce exhaust temperature. This necessitates compounding cooling capacity into the exhaust muffler. However, the aerodynamic performance, acoustic performance and structural size of the muffler are both interrelated and contradictory. This contradiction is further exacerbated by the increased cooling capacity of the exhaust cooling muffler compared to the exhaust muffler.

Therefore, the current common exhaust cooling mufflers are often unable to balance the above contradictions, and have many disadvantages such as large size, heavy weight, poor muffling performance, narrow muffling frequency band, and large pressure drop.

Accordingly, there is a need for a muffler that at least partially addresses the above problems.

SUMMARY OF THE INVENTION

A series of concepts in simplified form have been introduced in the Summary section, which are described in further detail in the Detailed Description section. The Summary of the Invention section of the present invention is not meant to attempt to limit the key features and essential technical features of the claimed technical solution, nor does it mean to attempt to determine the protection scope of the claimed technical solution.

In order to at least partially solve the above problems, the present invention provides a muffler, comprising:

a casing, the casing has an opposite outlet end and a closed end, the outlet end is provided with an air outlet;

an inner cylinder, the inner cylinder is disposed inside the casing and is spaced apart from the inner wall of the casing, the inner cylinder includes an expansion chamber;

an air intake pipe, the air intake pipe is communicated with the expansion chamber;

Wherein, the space between the side wall of the inner cylinder and the side wall of the casing is configured as a return air passage, and the return air passage is connected to the expansion chamber and the outlet end of the casing and the The space between the ends of the inner cylinder close to the outlet end.

Further, the inner cylinder includes a first inflation chamber and a second inflation chamber that communicate with each other, wherein the first inflation chamber is closer to the air outlet than the second inflation chamber, and the air intake pipe is communicated to the air outlet. first expansion chamber.

Further, the inner cylinder is provided with a baffle plate, the baffle plate is provided with a first opening, and the baffle plate divides the inner cylinder into the first expansion chamber and the second expansion chamber.

Further, the inner cylinder is also provided with a counter cylinder, one end of the counter cylinder is connected to the baffle, and the counter cylinder is spaced apart from the inner cylinder to form an inner air channel, the inner air The channel is communicated with at least two of the air inlet pipes, and the side wall of the hedging cylinder has a plurality of hedging holes, so that the gas entering the first expansion chamber can be hedged.

Further, the plurality of punching holes are evenly arranged along the axial and circumferential directions of the punching cylinder.

Further, the inner cylinder includes a transition air passage, the transition air passage is located between the intake pipe and the inner air passage, and the transition air passage is opposite to the intake pipe and the inner air passage. Tilt setting.

Further, the transition air passage is configured as a cone, and the cone top of the transition air passage faces the outlet end;

The air intake pipes are arranged along the radial direction of the casing, at least two of the air intake pipes are connected to the cone top of the transition air passage, and at least two of the air intake pipes are crossed with the connection of the transition air passage form a cone.

Further, the space between the outlet end of the casing and the end of the inner cylinder close to the outlet end is configured as a third expansion chamber, and the inner cylinder further includes an outlet end close to the casing The Helmholtz resonant cavity at the location, and the second opening communicated to the Helmholtz resonant cavity and the third expansion cavity.

Further, the housing has an inner wall, an outer wall, and a water cooling cavity formed between the inner wall and the outer wall, the outer wall has a water inlet and a water outlet, the water inlet is located at the closed end, so The water outlet is close to the outlet end.

Further, cooling water pipes spirally arranged along the circumference of the housing are provided in the water cooling cavity; or

The water-cooling cavity is provided with spacer ribs arranged spirally along the circumference of the casing, and the spacer ribs are connected between the interior and the outer wall to divide the water-cooling cavity into a spiral cooling water channel .

Further, the inner cylinder is connected to the side wall of the housing via a support rib, the support rib is configured as a heat dissipation fin, the number of the heat dissipation fin is at least two, and the heat dissipation fin is in the The return air passage extends along the axial direction of the casing, and at least two of the heat dissipation fins are evenly arranged along the circumferential direction of the casing.

Further, the inner tube includes a bent portion, the bent portion is located at the end of the inner tube close to the closed end, and is configured to protrude radially inward, so that the The inner diameter of the bent portion first decreases and then increases along the direction close to the closed end.

The muffler according to the present invention has the advantages of compact structure, light weight, simple maintenance, wide silencing frequency band, excellent silencing performance, good cooling effect and high stability, and has good economic benefits.

Description of drawings

The following drawings of the present invention are incorporated herein as a part of the present invention for understanding of the present invention. The accompanying drawings illustrate embodiments of the present invention and their description, which serve to explain the principles of the present invention.

In the attached picture:

Fig. 1 is the axial structure schematic diagram of the muffler according to the present invention;

FIG. 2 is a schematic view of a radially sectioned structure of the muffler in FIG. 1; and

FIG. 3 is a schematic diagram of a water cooling cavity of the muffler in FIG. 1 .

Description of reference numbers:

110: Housing 111: Outlet end 112: Closed end

113: Air outlet 114: Return air passage 115: Third expansion chamber

116: Inner wall 117: Outer wall 118: Water cooling cavity

119: Water inlet 120: Water outlet 121: Barrier

122: Cooling water channel 130: Inner cylinder 131: Helmholtz resonant cavity

132: First inflation chamber 133: Second inflation chamber 134: Bending part

135: Partition 136: First opening 137: Second opening

140: Hedge Cylinder 141: Inner Airway 142: Hedge Hole

144: Transition air duct 150: Support rib 160: Air intake pipe

100: Muffler

Detailed ways

In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. It will be apparent, however, to one skilled in the art that the present invention may be practiced without one or more of these details. In other instances, some technical features known in the art have not been described in order to avoid obscuring the present invention.

For a thorough understanding of the present invention, a detailed description will be set forth in the following description. It should be understood that these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of these exemplary embodiments to those skilled in the art. Obviously, the implementation of the embodiments of the present invention is not limited to the specific details familiar to those skilled in the art. Preferred embodiments of the present invention are described in detail below, however, the present invention may have other embodiments in addition to these detailed descriptions.

It should be noted that the terminology used herein is for the purpose of describing specific embodiments only, and is not intended to limit the exemplary embodiments in accordance with the present invention. As used herein, the singular forms are also intended to include the plural forms unless the context clearly dictates otherwise. Furthermore, it should also be understood that when the terms "comprising" and/or "comprising" are used in this specification, they indicate the presence of stated features, integers, steps, operations, elements and/or components, but do not exclude the presence or Addition of one or more other features, integers, steps, operations, elements, components and/or combinations thereof.

Ordinal numbers such as "first" and "second" referenced in the present invention are merely identifications, and do not have any other meanings, such as a specific order and the like. Also, for example, the term "first element" does not by itself imply the presence of a "second element," nor does the term "second element" by itself imply the presence of a "first element." It should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "inner", "outer" and similar expressions used herein are for illustrative purposes only , not a limitation.

Now, exemplary embodiments according to the present invention will be described in more detail with reference to the accompanying drawings.

Referring to Figure 1, a muffler of a preferred embodiment of the present invention is shown. It is generally composed of a casing 110 , an inner cylinder 130 and an air intake pipe 160 . One intake pipe 160 may be provided, or a plurality of them may be provided. Exemplarily, since diesel engines are often provided with two exhaust ports, the number of intake pipes 160 is preferably two. In this way, the pressure loss caused by the exhaust pipe connecting the two exhaust ports of the diesel engine entering the muffler after the muffler is conjoined can be reduced.

One end of the housing 110 is configured as an outlet end 111 , and an air outlet 113 is provided at the outlet end 111 . The other end is configured as a closed end 112 , and the closed end 112 is opposite to the outlet end 111 . The inner cylinder 130 is disposed inside the housing 110 and is spaced apart from the inner wall 116 of the housing 110 .

Preferably, at least two support ribs 150 are connected between the inner cylinder 130 and the side wall of the housing 110 to support the above-mentioned inner cylinder 130 . In the embodiment shown in FIG. 2 , four support ribs 150 are provided, and the four support ribs 150 are evenly arranged along the circumferential direction of the inner cylinder 130 . It is easy to understand that three, five, six or more supporting ribs 150 may also be provided, which is not limited herein.

The inner barrel 130 has an expansion chamber that preferably has an opening toward the closed end 112 . And the intake pipe 160 communicates with the expansion chamber.

In addition, the space between the side wall of the inner cylinder 130 and the side wall of the casing 110 forms a return air passage 114, and the return air passage 114 is connected to the expansion chamber and the outlet end 111 of the casing 110 and the outlet end 111 of the inner cylinder 130 close to the outlet. the space between the ends.

Preferably, the end of the inner barrel 130 near the closed end 112 is provided with a bent portion 134 configured to protrude radially inward. Specifically, it is configured to be bent radially inward and abut against the inner wall surface of the inner cylinder 130 . So that the inner diameter of the bending part 134 of the inner cylinder 130 first decreases and then increases along the direction close to the closed end 112 . Alternatively, the end of the inner cylinder 130 close to the closed end 112 may be configured as a constriction with a substantially arc-shaped top. This facilitates the gas to flow back into the above-mentioned return air passage 114 at an angle of 180°, thereby reducing the resistance loss.

Thereby, the gas enters the expansion cavity of the inner cylinder 130 from the air inlet pipe 160 for noise reduction, and then flows toward the closed end 112 of the housing 110 , and then enters the return air passage 114 and returns to the outlet end 111 to be discharged through the air outlet 113 . Such a backflow structure relieves the limitation of the size of the muffler in the length direction, increases the muffler stroke of the sound wave, and wins the cooling space. Compared with the existing muffler, the muffler 100 of the present invention has better muffler performance and cooling performance under the same length and dimension.

Further, two expansion chambers may be provided in the muffler, namely a first expansion chamber 132 and a second expansion chamber 133 that communicate with each other. The two are preferably separated by a partition 135 having a first opening 136 . The baffle 135 is located in the inner barrel 130 and is connected to the side wall of the inner barrel 130 .

The second inflation cavity 133 is close to the closed end 112 , and the first inflation cavity 132 is further away from the closed end 112 than the second inflation cavity 133 . The intake pipe 160 is connected to the first expansion chamber 132 .

The space between the outlet end 111 of the casing 110 and the end of the inner cylinder 130 close to the outlet end 111 can form the third expansion chamber 115 . The third expansion chamber 115 communicates with the return air passage 114 .

Thus, the gas enters the inner cylinder 130 from the air inlet pipe 160 and flows through the first expansion chamber 132 and the second expansion chamber 133 in sequence, then enters the return air passage 114 , passes through the third expansion chamber 115 and then is discharged through the air outlet 113 . The effects of multiple expansion cavities are superimposed, which further improves the muffler performance of the muffler 100 of the present invention.

Please continue to refer to Figure 1 below. Since the above-mentioned expansion cavity is mainly used for the elimination of middle and low frequency noises, in order to widen the noise reduction frequency band of the present invention, it is preferable to install the countersinking cylinder 140 in the inner cylinder 130 . Specifically, the hedging barrel 140 is disposed in the first expansion chamber 132 . One end thereof is connected to the partition plate 135 , and the other end is spaced apart from the bottom wall and the side wall of the first inflation chamber 132 to form the inner air passage 141 . At this time, the intake pipe 160 is communicated with the inner air passage 141 . A plurality of punching holes 142 are formed on the side wall of the punching cylinder 140 so that the gas entering the first expansion chamber 132 can be punched. Preferably, the above-mentioned plurality of punching holes 142 may be uniformly arranged along the axial and circumferential directions of the punching cylinder 140 .

Thus, the gas enters the inner air passage 141 from the intake pipe 160 , enters the first expansion chamber 132 through the punching hole 142 for hedging, and then enters the subsequent second expansion chamber 133 and the return air passage 114 . The hedging of the gas further reduces the resistance loss, so that the anechoic frequency band of the first expansion chamber 132 becomes a middle and high frequency band. Furthermore, the hedging structure widens the muffling frequency band of muffler performance of the muffler 100 of the present invention.

Continuing to refer to FIG. 1 , in order to further control the pressure loss, the inner cylinder 130 is further provided with a transition air passage 144 . It is located between the intake pipe 160 and the inner air passage 141 , and the transition air passage 144 is inclined with respect to the intake pipe 160 and the inner air passage 141 . In the illustrated embodiment, the transition air passage 144 is preferably configured as a conical shape with an apex of the conical shape facing the outlet end 111 . In addition, the air intake pipes 160 are arranged along the radial direction of the housing 110 , and at least two air intake pipes 160 are connected to the cone tops of the transition air passages 144 and form a crossed cone shape.

Further, a Helmholtz resonant cavity 131 is also provided in the casing 110 . In order to improve the compactness and further reduce the size, it is preferably provided at the outlet end 111 of the inner cylinder 130 close to the casing 110 . The Helmholtz resonant cavity 131 has a second opening 137 , and the second opening 137 communicates with the third expansion cavity 115 . Of course, the Helmholtz resonant cavity 131 can also be arranged in other positions. Since the Helmholtz resonant cavity 131 has a good silencing effect on low-frequency noise, it further widens the silencing frequency band of the muffler 100 of the present invention, so that it has good silencing performance at low frequencies, medium low frequencies and medium high frequencies. .

To sum up, the inner cylinder 130 is preferably constructed as a whole. It is a Helmholtz resonance cavity 131 , a first expansion cavity 132 and a second expansion cavity 133 in order from the end close to the outlet end 111 to the end close to the closed end 112 . The bottom wall of the first expansion cavity 132 separates the Helmholtz resonant cavity 131 from the first expansion cavity 132 , and the bottom wall is configured as a cone, that is, it can form a cone with the counter tube 140 whose bottom wall is also configured as a cone. A shaped transitional airway 144. In the illustrated embodiment, the two air intake pipes 160 pass through the inner cylinder 130 and enter the Helmholtz resonance cavity 131 , and are then connected to the cone top of the bottom wall of the first expansion cavity 132 . The return air passage 114 surrounds the Helmholtz resonance cavity 131 , the first expansion cavity 132 and the second expansion cavity 133 . The third expansion cavity 115 communicated with the return air passage 114 is located between the gas outlet and the Helmholtz resonance cavity 131 .

In addition, please refer to Figure 1 and Figure 3. The shell wall of the housing 110 is preferably configured as a water wall to compound cooling performance. The water cooling wall is preferably a double-walled structure, ie, configured to have an inner wall 116 , an outer wall 117 , and a water cooling cavity 118 formed between the inner wall 116 and the outer wall 117 . Specifically, the outer wall 117 is provided with a water inlet 119 and a water outlet 120 , the water inlet 119 is preferably located at the closed end 112 , and the water outlet 120 is preferably arranged near the outlet end 111 . In this way, water is injected into the water cooling cavity 118 from the water inlet 119, so that the muffler of the present invention can be given basic cooling performance.

In order to improve the cooling efficiency, cooling water pipes spirally arranged along the circumferential direction of the housing 110 may be provided in the water cooling cavity 118 . Alternatively, a spacer 121 connected between the inner wall and the outer wall 117 is provided in the water cooling cavity 118 . The partition ribs 121 are spirally arranged along the circumferential direction of the casing 110 , thereby dividing the water cooling cavity 118 into spiral cooling water channels 122 .

Further, the support ribs shown in FIG. 2 may be configured as cooling fins to enhance the cooling performance again. The heat dissipation fins extend along the axial direction of the casing 110 in the return air passage 114, so that the gas fully contacts the heat dissipation fins in the return air passage 114 for heat exchange, and the heat can be carried out by the cooling water, which strengthens the water cooling structure. cooling efficiency.

After testing, the muffler of the present invention has a high muffling amplitude in the whole frequency band, and the transmission loss in 220Hz-3200Hz is basically above 20dB, so it has a good muffling effect in the low frequency frequency below 500Hz.

According to the muffler 100 of the present invention, a plurality of expansion cavities are integrated, the length and size limitation is improved by using the backflow structure, the muffler frequency band covers low frequency, medium low frequency and medium high frequency, and the cooling structure such as water cooling is combined, and the structure is compact and light in weight. , Simple maintenance, wide silencing frequency, excellent silencing performance, good cooling effect and high stability, and have good economic benefits.

The processes and steps described in all the above preferred embodiments are only examples. Unless adverse effects occur, the various processing operations may be performed in an order different from that of the above-described flow. The sequence of steps in the above process can also be added, combined or deleted according to actual needs.

Unless otherwise defined, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field of this invention. The terminology used herein is for the purpose of describing a particular implementation only and is not intended to limit the present invention. A feature described herein in one embodiment may be applied to another embodiment alone or in combination with other features, unless the feature is not applicable in the other embodiment or stated otherwise.

The present invention has been described by the above-mentioned embodiments, but it should be understood that the above-mentioned embodiments are only for the purpose of illustration and description, and are not intended to limit the present invention to the scope of the described embodiments. In addition, those skilled in the art can understand that the present invention is not limited to the above-mentioned embodiments, and more variations and modifications can also be made according to the teachings of the present invention, and these variations and modifications all fall within the protection claimed in the present invention. within the range. The protection scope of the present invention is defined by the appended claims and their equivalents.

Claims (12)

1. A muffler, comprising:

the device comprises a shell, a valve and a control device, wherein the shell is provided with an outlet end and a closed end which are opposite to each other;

an inner barrel disposed inside the housing and spaced apart from an inner wall of the housing, the inner barrel including an expansion chamber;

the air inlet pipe is communicated to the expansion cavity;

wherein a space between the side wall of the inner cylinder and the side wall of the housing is configured as a return air passage communicating to the expansion chamber and a space between the outlet end of the housing and an end of the inner cylinder near the outlet end.

2. The muffler of claim 1 wherein the inner barrel includes a first expansion chamber and a second expansion chamber in communication with each other, wherein the first expansion chamber is closer to the outlet port than the second expansion chamber, and wherein the inlet pipe is in communication with the first expansion chamber.

3. The muffler of claim 2 wherein a baffle is disposed within the inner barrel, the baffle being provided with a first opening, the baffle dividing the inner barrel into the first expansion chamber and the second expansion chamber.

4. The muffler of claim 3 wherein a counterpulsation cylinder is further disposed within the inner barrel, one end of the counterpulsation cylinder being connected to the partition and spaced from the inner barrel to form an inner gas duct, the inner gas duct being in communication with at least two of the inlet pipes, the sidewall of the counterpulsation cylinder having a plurality of counterpulsation holes to enable counterpulsation of gas entering the first expansion chamber.

5. The muffler of claim 4 wherein the plurality of counter punched holes are uniformly arranged in the axial and circumferential directions of the counter barrel.

6. The muffler of claim 4 wherein the inner barrel includes a transition air passage between the inlet pipe and the inner air passage, the transition air passage being obliquely disposed relative to both the inlet pipe and the inner air passage.

7. The muffler of claim 6 wherein the transition duct is configured to be conical, the apex of the transition duct being directed toward the outlet end;

the air inlet pipes are arranged along the radial direction of the shell, at least two air inlet pipes are connected to the conical top of the transition air passage, and the connecting positions of the at least two air inlet pipes and the transition air passage are crossed to form a cone.

8. The muffler of claim 1 wherein a space between the outlet end of the housing and an end of the inner barrel proximate the outlet end is configured as a third expansion chamber, the inner barrel further including a helmholtz resonator proximate the outlet end of the housing, and a second opening communicating to the helmholtz resonator and the third expansion chamber.

9. The muffler of claim 1 wherein said housing has an inner wall, an outer wall, and a water cavity formed between said inner wall and said outer wall, said outer wall having a water inlet at said closed end and a water outlet proximate said outlet end.

10. The muffler of claim 9,

a cooling water pipe spirally arranged along the circumferential direction of the shell is arranged in the water cooling cavity; or

And a separation rib spirally arranged along the circumferential direction of the shell is arranged in the water-cooling cavity, and the separation rib is connected between the inner part and the outer wall so as to divide the water-cooling cavity into spiral cooling water channels.

11. The muffler according to claim 1, wherein the inner cylinder is connected to a side wall of the housing via support ribs configured as heat dissipation ribs, the number of the heat dissipation ribs being at least two, the heat dissipation ribs extending in an axial direction of the housing within the return air duct, and at least two of the heat dissipation ribs being arranged uniformly in a circumferential direction of the housing.

12. The muffler of claim 1, wherein the inner barrel includes a bend at an end of the inner barrel proximate the closed end and configured to project radially inward such that an inner diameter at the bend of the inner barrel decreases before increasing in a direction proximate the closed end.

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