Silencer for single cylinder diesel capable of reducing noise and emission and manufacturing method of silencer

[0041] Example 1

[0042] Such as figure 1 As shown, it is a single-cylinder diesel engine muffler for noise reduction and emission reduction according to the present invention, including: pipe joint 1, upper casing 2, lower casing 3, upper silencer net 4, lower silencer net 5, filter body 6, Vibration isolation pad 7, exhaust pipe 8 and sound-absorbing material layer 9, wherein one end of the pipe joint 1 is screwed to the exhaust elbow on the engine cylinder head, and the other end is fixedly connected to the lower housing 3. A groove body is provided between the lower shell 3 and the upper shell 2, and the exhaust pipe 8 is connected to the mouth of the upper shell 2 by a necking; the upper end of the filter body 6 is provided with the upper silencer Net 4, the lower end is provided with the lower noise-absorbing net 5, the two ends of the filter body 6 are respectively provided with outwardly extending vibration isolation pads 7; the filter body 6, the upper noise-absorbing net 4 and the lower noise-absorbing net The nets 5 are all arranged in the grooves between the upper shell 2, the lower shell 3; the inner walls of the upper shell 2, the lower shell 3 and the exhaust pipe 8 are filled with a layer of sound-absorbing material Layer 9; the cavity between the lower silencer net 5 and the lower shell 3 forms a first silencer cavity 10, and the cavity between the upper silencer net 4 and the upper shell 2 forms a second silencer Cavity 11, the space from the nozzle of the upper casing 2 to the exhaust pipe 8 forms a third silencing cavity 12; and the net ventilating cross-sectional area of ​​the first silencing cavity 10 is larger than that in the pipe joint 1 The net cross-sectional area of ​​the passage.

[0043] Preferably, a plurality of small holes of 3-5 mm are arranged on the upper noise-absorbing net 4 and the lower noise-absorbing net 5.

[0044] Preferably, the vibration isolation pad 7 is fixed between the upper housing 2 and the lower housing 3 by a bolt assembly 13.

[0045] Preferably, the filter body 6 is made of a high temperature resistant material, and is provided with a plurality of fine holes for passing and filtering exhaust gas.

[0046] Preferably, the sound-absorbing material layer is bonded to the inner wall of the upper casing 2, the lower casing 3 and the exhaust pipe 8 by an adhesive.

[0047] Preferably, the sound-absorbing material layer is one or more of temperature-resistant asbestos material, ceramic fiber paper, ordinary aluminum silicate fiber paper, and high-aluminum silicate fiber paper; the adhesive is high temperature resistant Metal adhesive. The high temperature resistant metal adhesive can withstand temperatures of 1500°C or higher, and the high temperature resistant sound-absorbing material can withstand temperatures of 1260°C or higher. Since the muffler described in this embodiment needs to be used with an engine, it is well known that the engine will generate a high temperature during use. Reasonable selection of high temperature resistant sound-absorbing materials and high temperature resistant metal adhesives can make the entire muffler use Better performance and longer service life. Those skilled in the art should know that the selection of the above-mentioned sound-absorbing material is only an illustration for the full implementation of this embodiment, and any other obvious changes and replacements fall within the protection scope of this embodiment.

[0048] Preferably, the upper casing 2, the lower casing 3, and the exhaust pipe 8 are made of steel plates with a thickness of 1 mm; the upper sound-absorbing net 4 and the lower sound-absorbing net 5 are made of 0.5 mm Made of steel plate.

[0049] Preferably, the filter body 6 is made of stainless steel wire mesh; the vibration isolation pad 7 is a high temperature resistant asbestos board.

[0050] Preferably, the vibration isolation pad 7 is fixed between the upper housing 2 and the lower housing 3 by 6-8 sets of bolt assemblies 13 of M4-6 mm.

[0051] The working principle of this embodiment is: adopting the method of adopting a three-stage ventilating net cross-section to gradually amplify and mute the sound, the air flow is alternately muffled from the large and small holes, and the sound-absorbing material is combined to mute the noise, which can reduce the noise by 20-25 decibels. The fine pores of the filter body 6 can have dual functions of silencing and filtering PM in the exhaust gas. Its sound absorbing mechanism combines the principles of resistive silencing, resistive silencing, micro-perforated plate silencing, small hole silencing and porous material composite sound absorption, which significantly reduces the audible components in the audio frequency spectrum, achieving filtering and reducing PM Effect.

[0052] Compared with the existing muffler, this embodiment has the following advantages:

[0053] 1. The single-cylinder diesel engine muffler with multi-stage composite noise reduction can reduce the noise by 15-25 decibels.

[0054] 2. The noise around the ear changes from the rough bounce sound to a soft popping sound after being silenced and filtered. The high, medium and low audible components of the audio frequency spectrum are significantly reduced, thereby reducing the interference and harm to people.

[0055] 3. After the exhaust of the engine is filtered, PM particles are adsorbed on the filter body 6, and the emission of particles is significantly improved.

[0056] 4. The connection structure of the bolt assembly 13 is adopted, and the filter body 6 is easy to remove and clean regularly.

[0057] Example 2

[0058] Such as figure 2 Shown is a method for manufacturing a single-cylinder diesel engine muffler based on the noise reduction and emission reduction described in Example 1, including the following steps:

[0059] S1: Prepare parts and components, including pipe joints 1, upper shell 2, lower shell 3, upper noise-absorbing net 4, lower noise-absorbing net 5, filter body 6, vibration isolation pad 7, and exhaust pipe 8;

[0060] S2: Connect the lower shell 3 to the pipe joint 1 by seam welding;

[0061] Seam welding the two halves of the exhaust pipe 8 into a whole;

[0062] Necking and seam welding the exhaust pipe 8 and the nozzle of the upper casing 2;

[0063] Place the filter body 6 between the upper noise-absorbing net 4 and the lower noise-absorbing net 5;

[0064] Combine the filter body 6, the vibration isolation pad 7, the upper noise-absorbing net 4, and the lower noise-absorbing net 5 and place them in the tank between the upper housing 2 and the lower housing 3;

[0065] The vibration isolation pad 7 is fixed between the upper housing 2 and the lower housing 3 by a bolt assembly 13.

[0066] Preferably, the step S1 specifically includes:

[0067] The production of the pipe joint 1: Rough and semi-finished steel pipe material with a wall thickness of 3mm to size, ream the thread, and cut the riveting groove body;

[0068] The production of the upper shell 2 and the lower shell 3: use a 1mm steel plate to pass 2-3 times of deep drawing, shaping and trimming, and punching; then go through pretreatment of grease removal and rust removal; coating on the inner wall High temperature resistant metal adhesive, bonding the sound-absorbing material layer;

[0069] The production of the exhaust pipe 8: the exhaust pipe 8 is made by seam welding of the upper and lower halves, which are stamped and trimmed with a 1mm steel plate, the exhaust pipe 8 is pretreated with grease and rust removal, and then Coat high temperature resistant metal adhesive on the inner wall to bond the sound-absorbing material layer;

[0070] The production of the upper noise-absorbing net 4 and the lower noise-absorbing net 5: punch a plurality of small holes of 3-5 mm with a 0.5 mm steel plate, and then trim the edges.

[0071] The manufacturing method of the noise reduction and emission reduction single-cylinder diesel muffler described in this implementation replaces the oxyacetylene welding process with the riveting and seam welding process. The quality is reliable, the appearance quality is significantly improved, and the corresponding productivity is also improved. 1-2 times. Moreover, it adopts three-stage amplifying and silencing of the ventilating net cross-section, alternating with large and small holes to silence the air, and the method of combining sound-absorbing materials to silence the noise, which can reduce the noise by 15-25 decibels. The fine pores of the filter body 6 can have dual functions of silencing and filtering PM in the exhaust gas. Its sound absorbing mechanism combines the principles of resistive silencing, resistive silencing, micro-perforated plate silencing, small hole silencing and porous material composite sound absorption, which significantly reduces the audible components in the audio frequency spectrum, achieving filtering and reducing PM Effect.