CN2869336Y - Exhaust pipe silencer for internal combustion engine - Google Patents

Abstract

The utility model relates to a gas engine exhausting noise canceling device, comprising a casing, an air inlet pipe, an air outlet pipe, an arc baffle plate, a cross slab, a connecting pipe and a punching cylinder, wherein the cross slab divides the cavity formed by the casing into a front expansion room and a back expansion room; the cut angle of the outlet of the air inlet pipe, which heads to the front expansion room and fits the arc baffle plate, is 45 degree; the connecting pipe, on which the front end is cutting shaped and located behind the arc baffle plate and the back end is closed and located in the punching cylinder of the back expansion room, where air outlet is provided on the circle of the back end side and, is inserted into the cross slab and connected with the front and the back expansion rooms; and small holes are provided on the punching cylinder. The device adds a special structure for changing air current innovatively and has the advantages of simple structure, hot-resistance, gas corrosion resistance, shockproof and long service life. The device can not only meet the noise reduction requirement of different types of gas engines, but also control the loss power of the mounted noise canceling device under 3% (with full load).

Description

A kind of I. C. engine exhaust muffler pipe

Affiliated technical field

The utility model relates to the internal combustion engine exhaust noise cancellation element, and specifically a kind of I. C. engine exhaust muffler pipe integrates resistive, resistance, perforation noise elimination structure, mainly is loaded on the exhaust sound of eliminating motor on the outlet pipe of various internal-combustion engines.

Background technique

Along with the fast development of Domestic Automotive Industry and communications and transportation cause, the traffic noise pollution problem has become influence and has created disturbances to big public hazards of resident living, and people's work and health have been caused huge negative.Control proposes more and more stricter index request to vehicle noise one after another in countries in the world.Internal combustion engine exhaust noise is the main noise source of vehicle, and along with the raising of internal-combustion engine rotational speed and reinforcing degree, airspeed strengthens in the vent systems, and exhaust sound also increases day by day, thereby causes the car load noise to increase.The relatively effective way of controlling combustion engine exhaust sound is to use exhaust silencer.Present China some silencing apparatuss except that car, adopt the theoretical study method based on the one-dimensional plane ripple, the sonimetry and the unstable analytic method that flows of one dimension of linear acoustic in design, so can't make accurate sound deadening capacity forecasting model and pressure loss numerical calculation model to silencing apparatus, and can't set up the acoustic wave filter structure parameter optimization model of taking all factors into consideration the sound deadening capacity and the pressure loss, thereby can't in certain scope, obtain the parameters combination of particular muffler the best.This causes having two kinds of defectives in the silencing apparatus of designed manufacturing, and a kind of is the excess processes that biases toward the noise elimination effect, causes the engine exhaust back pressure very big, and it is bigger that engine power is descended; Another kind of then be the processing that the partial-band noise is arranged, can't satisfy the further requirement of society to environmental protection.In view of the situation with along with the further developing of Domestic Automotive Industry and automobile consumption market, press for a kind of new and effective silencing apparatus of design, physical dimension is moderate, is unlikely again when effectively eliminating the noise that engine power is descended is bigger.

The model utility content

The purpose of this utility model is to overcome above-mentioned the deficiencies in the prior art, and a kind of novel I. C. engine exhaust muffler pipe is provided.

The purpose of this utility model realizes by technological scheme as described below.

A kind of I. C. engine exhaust muffler pipe, comprise shell, suction tude, steam outlet pipe, shell formation one has the cavity of cavity, suction tude and steam outlet pipe are contained in respectively on the front end and back end end face of cavity, the suction tude front end stretches out cavity, cavity is stretched out in the steam outlet pipe rear end, described silencing apparatus also comprises curved baffle, dividing plate, connecting tube and perforated drum, expansion chamber and back expansion chamber before the inside cavity that described dividing plate constitutes shell is separated into, the suction tude outlet end is 45 ° of otch, and deeply preceding expansion chamber cooperates with curved baffle; Described connecting tube is inserted on the dividing plate, is connected with the back expansion chamber with preceding expansion chamber, and its front end is made wedge shape otch, be positioned at curved baffle, its rear end sealing has relief opening on the circumference of side, rear end, be positioned at the perforated drum of back expansion chamber, have aperture on the perforated drum.

For further implementing the purpose of this utility model, the described suction tude front end that stretches out shell has adpting flange.The suction tude rear end of stretching out shell has adpting flange.It on the described perforated drum aperture that has based on He Lemuhuoci resonator principle design.The punching rate of described perforated drum is not more than 30%, and the perforation field of perforated drum is equivalent to the sectional area of muffler inlet pipe.Relief opening on the circumference of side, described connecting tube rear end is 4, is symmetrically distributed.

Principle of the present utility model: on the basis of grasping noise scientific principle opinion, aerodynamics theory and their numerical analysis method, introduce the gray system notion, the mathematical method of utilization gray Analysis is come the acoustic attenuation performance and the essential sound deadening capacity frequency characteristic of analysing and processing silencing apparatus model, sets up three-dimensional sound-attenuating system sound deadening capacity forecasting model and pressure loss numerical calculation model; And set up the acoustic wave filter structure parameter optimization model of taking all factors into consideration sound deadening capacity and power loss, in certain scope, obtain the parameters combination of particular muffler the best.According to this thinking, design provides a kind of new and effective silencing apparatus.It has diffusion, head-on collision, lags behind and fill out valley noise elimination form, make pulsing airflow obtain cutting apart diffusion, form mild air-flow, eliminate pulse noise, make it on wide band, to have acoustical absorptivity, add the perforated drum noise elimination structure and utilize the principle of helmholtz resonator, the interior noise of frequency band that control is approaching with the resonant frequency of helmholtz resonant cavity, make noise be controlled at the sensuously receptible level of the person as far as possible, and don't power reduce very big because the blast air resistance increases to cause motor.

The existing relatively internal combustion engine exhaust silencer of the utility model has the following advantages:

Adopt inner connecting tube double-outspreading cell-type structure, innovation ground has increased the special construction that changes air-flow, causes that by the variation of sectional shape sound impedance does not match, and makes that flow velocity reduces, sound energy attenuation, makes it have diffusion, head-on collision, hysteresis and fills out noise elimination forms such as valley.Muffler configuration of the present utility model is simple, high temperature resistant, the gasproof body corrodes and impact, longer service life, both on each frequency band, satisfied the necessary sound deadening capacity that corresponding internal-combustion engine proposes, the loss power of installation rear muffler can be controlled at below 3% (at full capacity) again.

Description of drawings

Fig. 1 is the structural representation of the utility model silencing apparatus;

Fig. 2 is the utility model noise-cancelling theory figure, and the arrow among the figure is represented airflow direction;

The comparison diagram of Fig. 3 test result, result of calculation and essential sound deadening capacity frequency characteristic;

The power loss situation map of Fig. 4 silencing apparatus under each operating mode.

Concrete implementation

Below in conjunction with drawings and Examples the utility model is further elaborated, but the claimed scope of the utility model is not limited to the scope that embodiment represents.

As shown in Figure 1, the I. C. engine exhaust muffler pipe, mainly form by shell 1, suction tude 2, curved baffle 3, preceding expansion chamber 4 and back expansion chamber 7, dividing plate 5, connecting tube 6, perforated drum 6, steam outlet pipe 9 by 45 ° of otch, shell 1 is a metallic cylindrical body, center, cylindrical shell one side end face is inserted with suction tude 2, and opposite side end face center is inserted with steam outlet pipe 9.Suction tude 2 one ends outside shell and the mouth of pipe place adpting flange is arranged, the other end then in shell and mouth of pipe place be 45 ° of otch.A curved baffle 3 is housed in the otch back.Immediately following curved baffle 3 back are connecting tubes 6 by dividing plate 5 centers.The dividing plate 5 that is contained in the housing centre is divided into former and later two spaces to whole cylindrical shell handle, and front end is the preceding expansion chamber 4 that is inserted with suction tude 2, and the rear end is the back expansion chamber 7 that is inserted with steam outlet pipe 9.Two expansion chamber are connected by the connecting tube 6 that is inserted on the dividing plate 5.The front end of connecting tube 6 is made wedge shape otch, and back-end closure is only opened the relief opening of 4 symmetries on the circumference of side, rear end.Perforated drum 8 is housed in the back expansion chamber, has been covered with aperture above based on He Lemuhuoci resonator principle design.Be contained in the same suction tude of steam outlet pipe 9 diameters on the ear end face, and the outer mouth of pipe is the same that adpting flange all arranged.

Fig. 2 is a process of further having illustrated the utility model realization noise elimination effect on Fig. 1 basis.After air-flow was come in from suction tude 2, its angular cut made the air-flow obliquely flow, and bump curved tailgate 3 produces reflected waves, interfered effect with the sound wave of incident air-flow, made sound energy attenuation (noise elimination) in preceding expansion chamber 4 diffusions again.Air-flow expansion chamber 4 in the past produces interference and collision once again in 6 two wedge shapes of connecting tube mouth enters the connection body, acoustic energy further reduces.The air-flow that weakens is expansion chamber 7 after 4 exhaust ports on the circumference of side, connecting tube 6 rear end enter, because explosion chamber is provided with perforated drum 8 structures in the back, its noise elimination structure is based on the principle design of He Lemuhuoci resonator, during it is fit to subdue, low frequency peak noise and make acoustic pressure further reduce, obtain bigger noise elimination effect.Then air-flow is discharged silencing apparatus through steam outlet pipe 9.Some only are the special constructions that changes airflow direction to whole silencing apparatus owing to adopted suction tude 2 structures that 45 ° of otch are arranged, curved tailgate 2 structures, wedge shape otch connecting tube 6 structures, intermediate clapboard 5 hierarchies, perforated drum 8 structures etc., do not dwindle the actual internal area of exhaust, therefore can not produce very high exhaust back pressure and reduce the power of motor, and the special structure of silencing apparatus its have diffusion, head-on collision to hold up effects such as filling in the valley and can obviously reduce exhaust sound.

Verify silencing apparatus noise elimination effect below by the stand test of model muffler being carried out under the different operating modes.

Fig. 3 is under Under Different Work Condition of Engine, the contrast situation at the exhaust sound frequency spectrum that the model muffler front and back are installed that test records.Fig. 3 has shown the comparison of the sound deadening capacity frequency characteristic that sound deadening capacity frequency characteristic and front analog computation draw, and also has both and the comparison of essential sound deadening capacity frequency characteristic simultaneously.Can find out obviously that from curve contrast test sound deadening capacity frequency characteristic is with to calculate the sound deadening capacity frequency characteristic identical substantially, the test measured value is higher than calculated value in the medium and low frequency section, at high band then a little less than calculated value; But no matter be test measured value or calculated value, all just above accordingly essential noise elimination value, satisfied the requirement of acoustic attenuation performance in each frequency range.

The power loss situation map of Fig. 4 silencing apparatus under each operating mode.As seen, the power loss of silencing apparatus is less, and the average loss basic controlling is in 3%, and the highest damage control is in 5.

Can judge from the contrast of test result and result of calculation, instruct this silencing apparatus of designing on combination property, both to satisfy essential sound deadening capacity, effectively control its power loss again by the computation optimization result.

Claims (6)

1, a kind of I. C. engine exhaust muffler pipe, comprise shell, suction tude, steam outlet pipe, shell formation one has the cavity of cavity, suction tude and steam outlet pipe are contained in respectively on the front end and back end end face of cavity, the suction tude front end stretches out cavity, cavity is stretched out in the steam outlet pipe rear end, it is characterized in that described silencing apparatus also comprises curved baffle, dividing plate, connecting tube and perforated drum, expansion chamber and back expansion chamber before the inside cavity that described dividing plate constitutes shell is separated into, the suction tude outlet end is 45 ° of otch, and deeply preceding expansion chamber cooperates with curved baffle; Described connecting tube is inserted on the dividing plate, is connected with the back expansion chamber with preceding expansion chamber, and its front end is a wedge shape otch, after being positioned at curved baffle, its rear end sealing has relief opening on the circumference of side, rear end, be positioned at the perforated drum of back expansion chamber, have aperture on the perforated drum.

2, I. C. engine exhaust muffler pipe according to claim 1 is characterized in that the described suction tude front end that stretches out shell has adpting flange.

3, I. C. engine exhaust muffler pipe according to claim 1 is characterized in that described suction tude rear end of stretching out shell has adpting flange.

4, I. C. engine exhaust muffler pipe according to claim 1 is characterized in that, is the aperture that has based on He Lemuhuoci resonator principle design on the described perforated drum.

5, I. C. engine exhaust muffler pipe according to claim 1 is characterized in that, the punching rate of described perforated drum is not more than 30%, and the perforation field of perforated drum is equivalent to the sectional area of muffler inlet pipe.

6, I. C. engine exhaust muffler pipe according to claim 1 is characterized in that, the relief opening on the circumference of side, described connecting tube rear end is 4, is symmetrically distributed.

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