CN101749089A

CN101749089A - Automobile muffler

Info

Publication number: CN101749089A
Application number: CN200810163266A
Authority: CN
Inventors: 李书福; 杨健; 包寿红
Original assignee: Zhejiang Geely Holding Group Co Ltd
Current assignee: Zhejiang Geely Holding Group Co Ltd
Priority date: 2008-12-12
Filing date: 2008-12-12
Publication date: 2010-06-23
Anticipated expiration: 2028-12-12
Also published as: CN101749089B

Abstract

The invention relates to an automobile muffler. The tail pipe of the automobile is respectively provided with a throttle valve and a stepping motor, wherein the throttle valve is driven by the motor, the motor is electrically connected with the electronic control unit of an engine, and the motor converts the rotation speed electric signal of the engine into a displacement signal, thereby driving the throttle valve to control the opening of the throttle valve. Since the throttle valve of the variable-displacement exhauster can track the variation of the engine rotation speed all the way so as to obtain the optimal control, so that the exhaust noise and the output power of the engine are better unified. The automobile muffler has the advantages of low cost and convenient installation, and is free from the restriction of assembly space.

Description

A kind of automobile muffler

Technical field

The present invention relates to a kind of automobile muffler, especially relate to the automobile muffler that a kind of energy intelligence is regulated extraction flow.

Background technique

Automobile exhaust system refers to the combination from the engine exhaust manifold to each parts of tailpipe.Generally comprise parts such as Y-piece, three-element catalytic, flexible pipe, premuffler, rearmounted silencing apparatus, intermediate connection tube, tail pipe, hook, hook vibration isolator, the silencing apparatus major function is to handle waste gas and reduce noise.Silencing apparatus mainly can be divided into resistance formula and anti-formula two classes by noise-cancelling theory.Resistance formula silencing apparatus is that the acoustic resistance effect that utilizes the sound-absorbing material on the silencing apparatus air-flow path wall that is laid in to produce is eliminated the noise.Anti-formula silencing apparatus is unexpected expansion or the contraction that utilizes pipeline section, or utilization produces acoustic resonance or acoustic interference, make in the noise some specific frequency content reflected back sound source or be subjected to significantly decaying and realize eliminating the noise, usually adopt the impedance complex formula silencing apparatus that combines by resistance formula and anti-formula different types at present.

In the prior art, the automotive muffler of various structures is arranged, it adopts concrete fixed structure more, is that a kind of automotive muffler of CN200610054365.8 is made up of cylindrical shell, three dividing plates, suction tude, steam outlet pipe and forward and backward end caps as application number.Dividing plate is separated into four chambers with cylindrical shell, suction tude puts in from cylindrical shell one end, end to the 3rd chamber through first, second, steam outlet pipe then passes second and third, picks out behind four chambers since first chamber, on suction tude, the steam outlet pipe and all have the micropore of some on the dividing plate, make first, second, third chamber form resonant cavity, can reduce low-frequency noise effectively.And the 4th to fill up sound absorption in the chamber cotton, forms anechoic room, also is surrounded by Sound damping cover in steam outlet pipe posterior segment periphery simultaneously, can further reduce high-frequency noise.The present invention is by three resonant cavities of design and an anechoic room, and cancelled transition tube, and make exhaust airstream flowing in noise elimination cavity more unimpeded, engine exhaust noise is effectively reduced in wide band, and can reduce exhaust back pressure effectively, improve the power of motor.

Usually the silencing apparatus volume is big more, and vent systems insertion loss is also big more, and the noise elimination effect is just good more.But its back pressure is also just big more, and power loss increases.When a vent systems was installed on the motor, the back pressure of exhaust ports increased, and vent systems will consume the power of a part of motor, if the sectional area of exhaust duct is big more, perhaps gas communication is smooth and easy more, and power loss is just more little.Reducing noise then needs pipeline section long-pending little, and the resistance that gas flow is subjected to is the bigger the better; During silencing apparatus, wish that the tailpipe noise is low more good more in design, wish that also the power loss of vent systems is the smaller the better simultaneously, will make power loss increase, so reducing noise and minimizing power loss are conflicting but reduce noise.

The muffler tail pipe noise is made up of two-part noise, airborne noise and air-flow frictional noise, and when the little and speed of flow was low, airborne noise accounted for main component, and flow is big and speed when fast, frictional noise accounts for main component.When 2700r/min was following, flow was less, and when the tail pipe diameter was big more, flow velocity was slow more, and the tail pipe noise is just high more; But the tail pipe diameter hour, flow velocity can be accelerated, so airborne noise can descend, and (because when the slow-speed of revolution, frictional noise is to the almost not influence of tail pipe noise, the tail pipe noise is fully by the airborne noise decision, and its size and silencing equipment are directly related with the ratio that pipeline section amasss).Bring up to 2700r/min when above when engine speed, when 4500r/min was above, flow increased sharply in the pipeline especially, and flow velocity also increases fast, and is more little as pipe diameter, and then flow velocity is just fast more, and the tail pipe noise is big more; When but the tail pipe diameter was big, flow velocity can descend, so tail pipe noise can descend (at this moment frictional noise plays a leading role, and the gas current friction noise accounts for main component).

Here just have a problem, if the outlet pipe diameter is less, when low engine speed, flow velocity can be accelerated, and airborne noise descends, and favourable tail pipe noise keeps reduced levels; But when high engine speeds, flow velocity can be faster, and frictional noise significantly increases makes the tail pipe noise keep a higher level.If instead the outlet pipe diameter is bigger, though frictional noise reduces during high speed, airborne noise obviously increases during low speed, so the outlet pipe diameter greatly or hour always have a unsurmountable shortcoming.

In the prior art, also have and adopt the dual exhaust system system, this is favourable to reducing the high rotating speed tail pipe of motor noise, but this can increase cost, also can be subjected to the restriction of assembly space, and the noise during engine low rotation speed can increase to some extent.

Summary of the invention

The present invention mainly solves the problems of the technologies described above, a kind of all-the-way tracking engine speed change is provided, exhaust sound is effectively controlled from low to high or in the whole process from high to low in engine speed, and promptly a kind of novel intelligence of passing through is regulated the automobile muffler that extraction flow is controlled exhaust sound.

Above-mentioned technical problem of the present invention is mainly solved by following technical proposals:

A kind of automobile muffler, at the automobile tail pipe closure and stepper motor are set respectively, closure is by motor driving, and motor is electrically connected the electronic control unit of motor, wherein motor is converted into displacement signal with the rotating speed electrical signal of motor, promotes the aperture of closure with the control closure.

The automobile tail pipe connects rearmounted silencing apparatus, and rearmounted silencing apparatus connects intervalve, since still bigger through the exhaust sound of rearmounted silencing apparatus, so need to regulate the automotive muffler of extraction flow.Intervalve and tail pipe that the intervalve of this installation adjusting discharge capacity silencer and the general uneasiness of section ratio of tail pipe are debug joint discharge capacity silencer are big, because the cross-sectional sizes of tail pipe is adjustable.Motor can be stepper motor or synchronous machine, on the tail pipe cross section closure is set, closure is subjected to step motor drive, and stepper motor is electrically connected the electronic control unit of motor, motor is when slowly running, exhaust sound is mainly airborne noise, and it is more little that discharge the cross section that air communication crosses this moment, and exhaust sound is more little, when high engine speeds is rotated, exhaust sound is mainly frictional noise, and it is big more that get rid of the cross section that air communication crosses this moment, and exhaust sound is more little.Stepper motor is subjected to electronic control unit controls, is angular displacement with the rotating speed electrical signal conversion, promptly according to the size of engine speed, and the size of step motor control angular displacement, thereby the aperture of control closure.

At the automobile tail pipe temperature transducer is set also, temperature transducer is electrically connected the electronic control unit of motor, is used for monitoring the variation of delivery temperature, and the position of closure is revised.When delivery temperature changes, the frequency and the wavelength of sound wave change, silencing apparatus itself is eliminated exhaust sound certain waveband selection, so exhaust sound is had very big influence, so need temperature monitoring, and closure revised, so that temperature is controlled to the influence of exhaust sound.

As preferably, in fix a support on the automobile tail pipe, stepper motor is arranged on the support.Stepper motor can't be set directly on the tail pipe, so fix a support on tail pipe, stepper motor is arranged on this support, more firm safety.

As preferably, be provided with the damping thermal insulating pad between tail pipe and the stepper motor.The temperature of exhaust is higher, and certain impact force is arranged, and the damping thermal insulating pad can be protected motor, and the damping thermal insulating pad can be arranged between support and the tail pipe, or between support and the stepper motor, as long as stepper motor and tail pipe can be separated.

Closure be one by step motor control and can be along the plate of central shaft rotation.Closure is tabular, its width is less than the cross-sectional width of tail pipe, when the closure original state, its obstruction cross section to air-flow is its front, air-flow is discharged from the vacancy of closure both sides and tail pipe, when the closure maximum opening, its obstruction cross section to air-flow is the side of closure, i.e. the thickness part.

The beneficial effect that the present invention brings is: when the outlet pipe diameter hour, the noise of motor when idling or rotating speed are low can be controlled, but can make the flow velocity increase that frictional noise is increased when high speed and make the tail pipe noise can not get obvious control; If when the pipe diameter was big, high rotating speed noise can be controlled, but slow-revving noise will increase, and the venting gas appliance that becomes discharge capacity can make motor hang down at rotating speed that noise all is effectively controlled in the high whole process.In addition, because Tail Pipe Temperature is when changing, the frequency of sound wave and wavelength can change along with temperature, and the venting gas appliance that therefore becomes discharge capacity can detect correction to delivery temperature, make the temperature can be controlled to the influence of exhaust sound.Variation that can the all-the-way tracking engine speed owing to the closure of the venting gas appliance that becomes discharge capacity obtains optimum control, make the exhaust sound of motor and output power obtain unified preferably.And this installation cost is lower, and is easy for installation, is not subjected to the restriction of assembly space.

Description of drawings

Accompanying drawing 1 is a kind of structural representation of the present invention;

Accompanying drawing 2 is A-A sectional structure schematic representation of the present invention;

Accompanying drawing 3 is part enlarged diagrams of accompanying drawing 2;

Accompanying drawing 4 is working procedure outflow figure of the present invention.

Embodiment

Below by embodiment, and in conjunction with the accompanying drawings, technological scheme of the present invention is described in further detail.

Embodiment: a kind of automobile muffler comprises temperature transducer 1, stepper motor 2, damping thermal insulating pad 3, support 6 and closure 5.The intervalve 8 of automobile exhaust system connects rearmounted silencing apparatus 7, rearmounted silencing apparatus 7 union tails 4, tail pipe 4 tops are provided with a support 6, and a damping thermal insulating pad 3 is set on the support 6, and damping thermal insulating pad top is provided with a stepper motor 2, stepper motor 2 is electrically connected the electronic control unit of motor, be provided with a closure 5 in the tail pipe 4, closure 5 is tabular, bilateral symmetry, can be around its central shaft rotation, closure 5 is by stepper motor 2 its angle of swing of control.The width of closure 5 is less than the diameter of tail pipe 4, along with the difference of the angle of swing of closure 5, regulates the lateral cross section size of closure 5 in tail pipe.In rearmounted silencing apparatus 1 end one temperature transducer 1 is installed, temperature transducer 1 is electrically connected the electronic control unit of motor, monitors the delivery temperature size in real time.

Engine electronic control unit is given stepper motor 2 with the rotating speed electrical signal transfer of motor, stepper motor 2 is adjusted the angle of swing of closure 5 according to the size of rotating speed, when rotating speed hour, because the tail pipe noise of this moment is mainly airborne noise, reduce the tail pipe diameter and help airborne noise decline, so should make the lateral cross section of closure bigger, the cross section that the discharge air communication is crossed is less, when engine speed increases, the tail pipe noise is mainly frictional noise, increase the aperture of closure, the cross section that promptly increases by air-flow helps reducing frictional noise.

During exhaust gas temperature change, the frequency of sound wave and wavelength can change along with temperature, like this will very big influence, and the venting gas appliance that becomes discharge capacity can detect and revise delivery temperature to the elimination of exhaust sound, make the temperature can be controlled to the influence of exhaust sound.Closure is when initial position, discharge the cross section minimum that air communication is crossed, this moment engine start, motor is in the idling work state, engine speed is very low, the closure initial position can just make the airborne noise minimum, promptly keeps the initial position of closure, the temperature sensor measurement exhaust gas temperature change, if temperature has no impact, keep the initial position of closure, and when temperature variation exerts an influence to exhaust sound, the position of closure is revised so that its influence is controlled.During vehicle starting because automobile will consume the starting smoothly of bigger power, therefore, closure ground zero moment will be certain aperture, according to operating mode aperture is being adjusted after playing EOS.When rotating speed is brought up to 2700r/min, frictional noise plays a leading role, electronic control unit is according to the angular displacement of the rotating speed control step motor of motor, the rotation of step motor drive closure, the angle of swing of closure is corresponding with the angular displacement of stepper motor, angle of swing is big more, and it is big more then to discharge flow area, and frictional noise is more little.After vehicle starting finished, the position of closure adjusted according to the speed of a motor vehicle and delivery temperature.Automobile is when reversing, and is similar during with vehicle starting, after rotating speed reaches certain numerical value, and the rotation of electronic control unit controls step motor drive closure, throttle opening maintains certain aperture.After motor stopped, closure returned to initial position.

Claims

1. automobile muffler, it is characterized in that closure (5) and motor (2) being set respectively at automobile tail pipe (4), closure (5) is driven by motor (2), motor is electrically connected the electronic control unit of motor, wherein motor (2) is converted into displacement signal with the rotating speed electrical signal of motor, promotes the aperture of closure (5) with the control closure.

2. a kind of automobile muffler according to claim 1, it is characterized in that temperature transducer (1) also being set at the automobile tail pipe, temperature transducer (1) is electrically connected the electronic control unit of motor, is used for monitoring the variation of delivery temperature, and the position of closure (5) is revised.

3. a kind of automobile muffler according to claim 1 and 2 is characterized in that fixing a support (6) on the automobile tail pipe, motor (2) is arranged on the support (6).

4. a kind of automobile muffler according to claim 3 is characterized in that being provided with damping thermal insulating pad (3) between tail pipe (4) and the motor (2).

5. a kind of automobile muffler according to claim 1 and 2 is characterized in that described closure (5) is a rotatable plate by Electric Machine Control.

6. a kind of automobile muffler according to claim 4, it is characterized in that described closure (5) be one by Electric Machine Control and can be along the plate of central shaft rotation.