DE1810158A1 - Device for regulating the gas flow - Google Patents

Description

Dr. F. Zuimtein - Dr. E. Assmann Dr. R. Koenirjsberger Dipl. Fhys. R, Holzhauer 1 Q 1 Π 1 C Q

PoienianwäHe '0 IU I JO

Munich 2, Bräuhausstralje 4 / lit

SC 3227

! HONE POULENC, S.A., PARIS / FRANCE

DEVICE UNO FOR REGULATING THE GAS FLOW RATE

The present invention relates to an apparatus for Regulating gas flow the sudden and in particular have pulse-like pressure fluctuations. In particular, it relates to a device for regulating exhaust gases of internal combustion engines.

It is well known that gas flows can cause sudden fluctuations in pressure have, for example, as a result of his sudden opening from HShmm, Drosseini, Schieber. " or valves, üs is it is also known that certain gas streams can have pulsations. Among these one can see the gas flow in a pipe, in which a pulse flow develops, or else call the stream of gas «emanating from devices, which as a result of their structure, they generate pulsating currents for example reciprocating compressors or internal combustion engines.

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Attempts have been made to regulate these flows ", in particular by means of baffles or baffles or similar devices in lines in which such flows occur, these devices causing quite considerable losses and pressure drop effects, which determine the throughput" la "· has also combined systems of expanelon cameras with devices with harassment or analog devices. In general, these devices have a rigid structure.

When a pulsating gas flow Yorttenden in a pipe is, then this pulsation (or its Harmonic) on the line itself; ,, being on this mechanisch® transmits stresses that look detrimental to this can affect »To avoid this phenomenon, metal bellows have been used to give the lines a certain Give flexibility.

It is known »that all of these solutions have disadvantages, like considerable losses, large space requirements and insufficient effect, so that the selection of a suitable device is not based on predetermined conditions but flour «happened by chance.

The problem becomes even more difficult when it comes to hot gases, which can have a corrosive effect on the metals of which such devices are generally made. The problem is particularly difficult in the case of Ayspuffgasen to solve won internal combustion engines. The foppieiittimgen used, which are usually called "exhaust ^{mufflers Ef} , beststaa generally from rigid components". However, some embodiments are known in which the © lasfeisclie deformation of the components is exploited.

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Tentschrlften 2 859 8JO and 2 877 860 mufflers be written, which have components made of elastomer materials. In all known devices, the gases have to flow through complicated channels or through narrow slots, so that the pressure losses in these devices always remain very high.

It is also in the case of mufflers for motor vehicles necessary to have a device that is as light as possible «which is also weatherproof. Also in this regard has As is well known, the problem has not yet found a really satisfactory solution.

The present invention relates to a new device that enables. Gas flows, the sudden pressure fluctuations un particular have pressure pulses to regulate it, ie "very easy iet and Oasis to a temperature of JOO ⁰ C can be used and their chemical inertness almost completely eliminates the risks of corrosion and causes only losses that are practically vernachlfissigbar .

The device according to the invention for regulating the throughput of gases is characterized in that it has at least one effective section with a wall; exhibits * the under the influence of shocks dec dynamic pressures of the oasetrome and practically proportional to these fluctuations elastic deΓοΐτ ·:!. <?: - 1;?. · -: ■ is and the gases over the entire length ί, ην -ev T'urch.str - "> niungstßhn a passage cross section Ia ¹ ESI · <ier £ uinJ; r.3'_ ■ :: <: equal <From left to right HHIfte dee cross section ε of VorrtohUunKf ¹ ··· * r> the hfttrn place is.

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Yorzugswelee, the deformed "]? · Section cross turns on, hurry connected and arranged so that the gas flow impinges on them to the wall. These transverse walls facilitate the mechanical take-along wall.

The preferred embodiment of the Eeguliepungswopploiitung is an exhaust pot for internal combustion engines and in particular a muffler for motor vehicles.

The embodiment of the invention in pore of a muffler for ipeffefeliPEeiige provides that represents for the difficulties are maximum, and the invention will -a restriction made as »forth in the following on, hand this Ausführungsfosw © riSuterfc without hereby the scope of the invention values target.

ΓJη oirSiicJvrtfTCOiilsser muffler as in Selmiifefe JL Iiewatintl 'filtiit nasesiabSL loyal la the Zeielmwng

cLtIH "J" *! *, if «niß one in essence uv ^p , döi on the exit ear M dei pnxrl Wf Ijb T Jleeep Abe ^ Imii H» alt © In «ütoiefciiltfe i al, VtV ₁ ^, 'jjLßilwiig äefrTslhm. is ηηύ des? in turn nil etIl t ijfislichen zjllmlTlaQhsm ßbselisiifcfc J ψ © ρ ~ ip 11 ^'11 ILi ι ⁴ I i den see ( ¹¹ Ia Frof Jlcbostai'efc 4 TiI ¹ Ti ' i ^t fli noßelmitt ^J J ¹ OIt with one in $

1ι "p Pu ^r n ~ jiMitt 5 connected via smf dera exhaust pipe

The Alisc5 '"ji * itt old of the defopaiierlbapen Masidiüig K? S3st firmly attached spiral coils 6, 7s 8 on _s <äi © desi feil de

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At least the deformable section is made of an elastic, resistant to the action of exhaust gases Material (preferably a material based on Slllconelastomerem) produced.

The transverse walls can be made of any material which is resistant to the effects of the gases and which can be firmly connected to the deformable wall be. They are preferably made from a material based on silicone elastomers, optionally in a reinforced shape.

Preferably, the overall assembly is made from a silicone elastomer, and each section can be reinforced with any structural member to make each section To give the appropriate heat resistance, mechanical strength and elasticity for its function.

The dimensions of each section are not critical. They are depending on the usual design rules the displacement and the performance of the equipment Motor determined.

The number and dimensions of the transverse walls are important. These should be arranged in such a way that the plane is essentially perpendicular; ) ht is to the main stream direction, and se, that :: none3 of them 5? .nr arodynaml- = sch © shielding for the Jc'olgonda transverse wall biidefc,

They can consist of circular rings, the-on inner :: · diameter in the main direction of flow of the gases gradually decreases. The transverse walls are preferably simple rings segments., the highest half of the Durohgangsejuar-

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Complete cuts of the oasis and alternate to both Sides of the axis of orientation are arranged »So a deformable chamber is formed by the space, which is limited by the various transverse walls.

The function of the muffler according to the invention is as follows: The gas flow generated by the exhaust cycle of a cylinder passes through the pipe 1 and strikes the transverse wall 6 Flow direction takes. Since this transverse wall is firmly connected to the deformable wall 2, a deformation of this deformable wall occurs, which absorbs part of the energy of the gas surge and thus reduces the initial pressure surge. This energy is fed back to the gas mass "when the main amount of gas has flowed past the transverse wall," ofciii the pressure of the last part of this gas mass is increased "This results in a flattening of the pressure curve of the gas surge". The same phenomenon occurs between the transverse walls 6 and 7 » then between the transverse walls 7 and 8» etc., depending on the number of transverse walls _s ,

The pressure gap between the front flank of the Oasstosses and the end of the ßasstossas diminishes each time you pass a transverse wall, and after you have flowed a sufficient number of quayside over time, you get an equalization of the pressure and a Outflow _P that approaches a brisk! Massive outflow ₀

From the foregoing, it is sufficient that the dimensions of the Transverse walls, the dimensions of the deformable section and the misleading of the elastic movement of the quesaffle arrangement to the Foluiien of the discharged

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Oaae and the largest oruok sub-rivers in the oasis rivers should be related. Adaptation to the operating conditions of a particular engine is therefore a matter of practice. Ee seems « that the best mode of operation is obtained when a Chamber can work elastically in the same rhythm as that of the Qass pushes.

From the above discussions it can be seen that the shape of the deformable wall is not critical, but it is it has been found in practice that the most advantageous shape is the shape of a bellows with circular or spiral folds.

The inherent elasticity of the material from which the wall is made can be used, but the possibility of elastic deformation of each chamber can also be influenced by forming the deformable wall in the form of a bellows with spiral folds and inserting them Folding one or more spirally wound elastic metal wires uses _t, for example, one or more spirally wound steel wires.

It was also found that: in conical bellows with regular in-flow direction, grows in the diameter especially toiYiedttnstellmiüu .irgebnicr; «· 3; <<if;; - ■ '.- ,.

The walls in Hai ienf'v, α. Μ, κΐ infjJ.ßo c'er! .EichtA ₁ ^ n. It with the s.ie Sieb de J V. rmier.-ϊπ, vor'i. ¹ i '< , iia.f t. H / ndu ^ ch will 68 m'ißllch, dit; Rejection her. · Qv- . · Ίη'ί'.τ: who serve ^{nis takeaway 1} , 2, Vf ^ mindoÄ · !. Xn many ^ iI j..Von germinate d1 ■ se cino simple Vei'lHngci \ n \ [,. der £ <sc-.iinlkoriti η o.it.r,;. ; Inner foldiii) min and often with ck; r "choiit'll · ori ■ π <Λ \ <.:> ■

^ÖAD ORIGINAL 903831/0828

Form a whole »especially in the case of conical bellows "

An essentially cylindrical section adjoins the elastically deformable section. 3 and then a profile section k , which is then connected to the exhaust pipe by section 5. The Sylndrise section can optionally be made separately from another material and * used if desired. For example, a metal ring can be used.

The dimension of this Abschnitt® is not critical "but should be noted that dl © overall arrangement of cylindrical section - profile section is a BeruhigungsScammer and the choice of profiles toit Dopp @ lkrÜBMu" ig _£ which are common in ignition chambers to a reg® massive outflow of Awb «intake gases contributes at a considerable exhaust velocity. Choosing the same construction material for this section as for the elastically deformable section, but with appropriate reinforcement to maintain the shape, gives the overall structure a low level of elasticity, which helps to dampen the vibrations with sound frequencies that may be present in the flow.

Of course, this section can be provided with a coating of absorbent material, such as silicon fiber, or with various surface irregularities in order to form a suitable boundary layer * or vibration damping structure, aonh i & * aios Ranz generally not necessary * and a smooth one is preferred Inner wall with inner cortex, which leads to © inc-m rf; «· gelmKfislgcm outflow.

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In the case of other irregular, in particular pulsating, gas currents, analog devices can be used. For example, a device can be used in a compressor delivery line which consists only of a deformable part in the form of a cylindrical bellows made of elastic material which is reinforced in such a way that it withstands the static pressure. The dimensions of the chambers are adapted to the pulsations of the gas flow. When the internal pressure is so great that the bellows is no longer simultaneously _s has derstehen to the static pressure of the oases to wi- ™ sufficient ^ strength and an acceptable attenuation to enable the pulsations sufficient elasticity, brings to the inventive damping device into a sealed metal tube, in which a pressure of the same order of magnitude as that in the line is set, which makes it possible to give the deformable wall a sufficiently small wall thickness and flexibility.

Anyone skilled in the art can use the device according to the invention easy to interpret for the case at hand.

The inventive device may be integrally formed depending on Zweckmäs- Jt slgkelt or be assembled from several parts. In particular, it can be "manufactured" in the form of retaining shells that are assembled lengthways. The device can be manufactured using the techniques customary for the material used, such as molding, application, vacuum or pressure molding and other molding processes.

The only essential point is that the details of the embodiment chosen and the material, 8o as it is from its type and the manufacturing process used

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results _{s are} such that they enable the deformation provided for the elastically deformable section. As a material for producing the erfindungagemässen devices can use all © materials to the action of a @ r gases resistant and © ine mechanisch® sufficient strength and elasticity have "Xn some cases Metall® be used in other cases elastomers such as for example natural or synthetic rubbers, if necessary in a correspondingly provided or reinforced form "

Mail can use the fluorine-containing elastomers, in particular However the fluorine-containing silicone elastosasers or pure silicone call elastomers ^ or the usual silicone elastomers, oil © are made of rubbers with linear chains »which from a chain

I I I

- Sl - 0 - -Sl - 0 - Si -

ι I!

exist, wob®! dl © free valences of the "Siliciumatonae are by organic radicals such as methyl _s' vinyl, phenyl ·», and the like. Best, abgesMttigt * The linear chain may also consist of a silicon »¥ Aryleo- ®rkettung, for its temperature resistance is known, such as di® concatenation

I I

the organic residues serving the others drains of silicon "saturate, of the same kind as are for the siloxane chain,

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Si - C ₆ H ₄ -Sl- C ₆ H ₄ - Si

The elastomer compositions using these Rubbers are known. Those «which maintain the highest temperatures are preferred, these being in the Vulcanize heat or at room temperature.

As elastomers that self-vulcanize in the cold, the ones described in French patents 1 198 7 ^ 9 and 1,266,528. These elastomers are known and widely used commercial products,

For example, the silicone elastomers that contain an organopolysiloxane rubber with a average molecular weight in the order of magnitude from 450,000 of the general formula

Si -

0 - Si -

Rc

-0 Si

contain "in which the radicals R ₁ ■ = · R ^ straight-chain" or branched alkyl radicals with 1 to k carbon atoms, straight-chain or branched alkenyl radicals with 2 to 4 carbon atoms, aromatic radicals or cyeloalkyl radicals with 5 to 6 carbon atoms "mean-υη, these Best known as substituents are one or more alky groups with 1 to 4 carbon atoms or one or more halogen atoms, such as, for example, fluorine, these; Biljt.conel & εstomere fernei ' Qimm orgatiophil <<} ./ Silicic acid JEMi \] substance, such as baj-splcilswel & c p, - / roe her-

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BATH ORIGINAL

Manufactured silica g containing and being these rubbers crosslinked by a vulcanizing agent of the benzoyl peroxide type are.

Al © VerstSrkungsiaaterielien which to Binue "determines a particular portion of the erflndungsgemSsse" device to impart the desired mechanisch® strength or elasticity, it can be all in the production of products based on elastomers usual Materia "lien, as examples, tissue * .Glasgewebe * ffetaiigewete and others, name. Local ornamental elements such as metal plate, steel wire and the like can also be used.

The use of the materials suitable in a particular case and the grinding of the reinforcing agents and inserts is a simple matter of practice.

In particular, the choice of materials of the first transverse wall, the physical and chemical conditions of the oasis are there impinges directly specifically to bertiokeiohtigen * to this first transverse wall, the Gae whose throughput is ren to regu ".

In the case of a muffler, for example, it must be taken into account that the temperature of the gases can be quite high , that material particles can be carried along and that there can be liquid combustion residues in the gas flow. The adaptation of the bulkhead to the composition of the exhaust gases and their nature is therefore important. The production of this transverse wall from @ in @ m silicone elastomers which are resistant at high temperatures and which are reinforced with a metal fabric inlaid in the mass

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is or even in the form of a metal plate attached to the elastic wall made of silicone rubber glued with the help of a silicone rubber vulcanized in place can be a satisfactory solution in certain cases.

Since the exhaust gas generally from the engine with a temperature of about 8OO ^e C emerges, the inventive muffler is disposed to a metal pipe, which allows the oasis that to cool to a temperature of about 300 ⁰ C, as in the rest of motor vehicles is common.

The following example explains the invention without restricting it.

example

A motor vehicle is used with its 4-cylinder engine has a displacement of 1468 cnr and is operated at a normal speed between 1000 and 5000 rpm.

One arranges between the pipe leading from the gas outlet of the Engine goes out, and the exhaust pipe a muffler according to the invention, as shown in the drawing, at.

The elastically deformable portion consists of a bellows made of a silicone elastomer with a molecular weight from 450,000 of the formula

Si

0 - Si -

-OSi (CH ₃ ).

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with a content of 30 $ fumed silica, which is vulcanized with 2,4-dichlopbenzoyl peroxide.

The bellows has circular folds »with the depth the folds is 10 mm. The tree has 20 folds. Its minimum diameter next to the oasis inlet is 30 mm, its maximum Durohmesser 130 mm and its se » total length 300 mm. It is equipped with a gas supply line E 20 mm in diameter over a cylindrical section tied together.

This bellows is followed by a cylindrical section with a diameter of 150 mm and a length of 30 mm, which is followed by a section with a double curvature with a length of 500 ram, which is a cylindrical section 40 mm in diameter and 50 mm in length @ nd @ t _s which is connected to the exhaust pipe of the vehicle. The double-curved section consists of an identical silicone elastomer reinforced with a glass fabric and stiffened by a 0.5 mm spiral steel wire, the spirals of which are 10 mm apart.

The bellows has three semicircular transverse walls, which are arranged alternately and regularly distributed those made from silicone elastomers «! the analogous general formula »which, however, has phenyl radicals in place of the methyl radicals, consists. These transverse walls are connected to the bellows by means of a silicone elastomer that vulcanizes in the cold glued.

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It is found that the oasis has the following temperatures exhibited outlet temperature of the exhaust gases on

Exhaust pipe at extremely low Motor speed: 38 ⁰ Cf

after 10 mlnUtlger acceleration: ⁰

One finds that the muffler comes in handy too regular ejection leads and the explosion sound is very well damped. It is found that the deformable section "works" in accordance with the pulsations of the gas flow emerging from the engine. The overall arrangement is mechanically and satisfactorily with regard to the combustion products. The overall arrangement is 1st very light, it weighs 600 g and it does not require mechanical attachment to the body. It is completely weatherproof.

Am metallic muffler of the usual type for a Vehicle of this type weighs 5 kg.

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Claims (1)

Claims 1, device for regulating the throughput of Gases * characterized by at least one section «which consists of a wall» which is under the influence of fluctuations in dynamic pressure, ß & ssfcronis and Essentially proportional to these fluctuations, it is elastically deformable and the gases over the whole Length of their flow path a Strönamgsquersohnit-t Isst, which is at least equal to the HSIfte of the cross-section of the device on the considered fabric. 2 * device according to claim 1, characterized in that that they also have a profile for a uniform Having distribution of the discharge at the outlet section. 90983 1/0828