DE102004014314A1 - Intake device used especially for an internal combustion engine comprises a multipart conduit section for guiding intake air that has an air-impermeable structure and a porous structure - Google Patents

Abstract

Intake device, especially for an internal combustion engine, comprises a multipart conduit section (10) for guiding intake air. At least one part (11) of the conduit section has an air-impermeable structure and at least one further part (12) of the conduit section has a porous structure. Preferred Features: The air-impermeable part is made of injection-molded plastic and the porous part of open-pored extruded plastic.

Description

State of technology

The The invention relates to an intake device, in particular for an internal combustion engine, with a conduit section, which air-permeable and air-impermeable areas comprises, according to the preamble of claim 1.

The attachment of breakthroughs, in particular holes, z. B. from the DE 16 42 857 known. According to this document, the intake manifold of an air filter housing is provided with a series of holes. In order to limit the number of holes for manufacturing reasons, these are designed in a sufficient size to achieve the desired acoustic effect. The holes create short circuits of the tube volume with the environment beyond the tube wall. As a result, the formation of standing waves is suppressed or reduced in the pipe and thereby achieves a damping of the intake noise.

The Environment of the pipe is usually formed by the engine compartment, in the other components of the internal combustion engine are arranged. However, due to the short circuit of the engine compartment with the pipe interior leads the pulsation of the intake air to a vibration excitation of others Components in the engine compartment, what additional activities for vibration damping may be necessary. It can also be over the Holes come to a suction of hot air from the engine compartment, said As a result, the performance of the internal combustion engine is reduced. Otherwise means the attachment of holes in the pipe socket an additional Production costs, which reduces the efficiency of the component. This can only be limited by only a small amount Number of holes is provided.

you could now use a fabric hose as a line section, the one certain air permeability to the environment. Although these components have optimal acoustic properties, but are expensive to produce. In addition, creates the connection to the suction device an additional manufacturing and assembly technology Effort.

In the document DE 32 34 633 an air filter for internal combustion engines is disclosed. The air filter has an air inlet nozzle, which has radially arranged holes. The holes are located in two belts, reducing the intake noise level. The intake manifold is designed as a one-piece unit, whereby the introduction of the holes is expensive.

Furthermore, the disclosure DE 91 13 807 an air filter for an internal combustion engine, which has a Rohluftansaugstutzen, a filter housing and a clean air outlet. Starting from the clean air outlet, a clean air outlet protrudes into the clean side of the filter housing. The clean air connection has holes, which are intended for noise reduction. The clean air pipe is designed as a one-piece unit, with a complicated tool for producing the holes is required.

The The object of the invention is the creation of a line section, especially for the intake tract of internal combustion engines, with optimal noise-damping Properties that are economical to manufacture and one Low vibration influencing of adjacent components in the engine compartment entails. This object is achieved by the features of the claim 1 solved.

Advantages of invention

The intake device according to the invention, in particular for an internal combustion engine, has a line section for guiding the intake air, wherein the line section is designed in several parts, that is, at least in two parts. In this case, at least a part of the line section has a substantially air-impermeable structure and at least one further part of the line section has a porous structure. Preferably, in this case, the air-impermeable part of a plastic, such as polyamide (PA) or polypropylene (PP), prepared and the porous or open-celled part also made of a plastic, eg. As PP or PE with an average pore width of about 30 microns, executed, the pore size may vary depending on the application up or down. By the execution of one part of the line section of an open-pored, porous structure, very advantageous acoustic properties of the overall system result. It is easily possible to achieve attenuations of up to approximately 1000 hertz in this manner, and this 1000 hertz should not be understood as an absolute end range. Due to the very small pores of the open-pored, porous material by default there is no vibration excitation from surrounding components and, moreover, almost no warm air is sucked out of the engine compartment, so that virtually no performance deterioration of the internal combustion engine occurs. The line section according to the invention may in this case have any hollow cylindrical shape, but preferably substantially round or oval shapes are used. Due to the possibility of extruding and / or injection molding of the open-pored, porous plastic material, it is very easy to form special contours adapted to the surrounding space and thus not having to accept any restrictions with regard to the installation situation.

According to one advantageous embodiment of the invention, the division plane runs between the differently structured parts parallel to the flow direction. This variant includes manufacturing advantages, as the different parts of the line section in this way can be easily connected with each other. As connection type is Here, for example, gluing, welding or mechanical types of connection via clamps, Called snap connections or such.

A advantageous embodiment of the invention provides that the line section have two substantially air-impervious partial pipe shells, wherein in the separation plane between the subcircuit partial shells, respectively a strip-shaped, porous line section is arranged. Preferably, the air-impermeable partial pipe shells in this case a semicircular Cross-section, which is easy to manufacture, and the strip, porous Line section can be so easy to produce by extrusion and thus can also economical getting produced. Preferably, the substantially air-impervious partial pipe shells at its edges a groove, wherein the strip-shaped, porous line section corresponding a tongue-and-groove system is held. However, it is just as possible that Connection via z. B. an overlap, which then glued, welded or connected to each other by means of another type of connection can be realized.

According to one Development of the inventive concept is the porous strip each in a correspondingly shaped groove of the partial pipe shells embedded and the sub-shells are over the porous strips across a Clip connection connected. At a corresponding Forming the groove in the partial pipe shells with a slight after inside inclined edge on the outer contour the cable part shell and a corresponding thereto executed snap hook on the second cable part shell, it is easily possible, both Clipping parts together. However, it is equally possible that Clip connection over the to lead the entire circumference of the cable part shells and there with itself to clip. The important thing is that the clip connection enough force in the radial direction on the line sections exerts to the Line sections non-positively to connect with each other.

A Further modification of the invention is characterized in that the conduit section is a substantially air-impermeable partial conduit shell and a porous one or also has open-pore partial tube shell, wherein the dividing plane in the axial direction, that is substantially parallel to the flow direction, runs. In this case, the line section preferably has a part-circular cross-sectional shape on, with the division plane approximately in the middle of a complete circle runs, so that two semicircular Partial pipe shells arise. The partial pipe shells are either mechanically over a clip connection or screw, rivet or drilling connections connected with each other. However, there is also the possibility these two subshells over an adhesive or welded joint to connect with each other. Characterized in that preferably semicircular partial pipe shells used, there is a great advantage in the production, because the parts under the simplest conditions, eg. B. in the injection molding process, can be produced.

According to one Another embodiment of the invention, the substantially airtight housing shell a substantially U-shaped Cross section and the porous Housing partial shell surrounds an angle between 180 ° and 120 °. Thereby is the porous one or open-pore housing shell executed relatively flat and resembles this a porous, open-pored cover. Because of this type of design a certain inner area ratio between the substantially impermeable to air Housing partial shell and the porous, open-pored partial shell results, can be so very positive acoustic damping effects achieve. Here, however, must be said explicitly that this effect even at slight amended Angle divisions can be achieved.

It is advantageous, the substantially air-impermeable conduit parts made of injection-molded plastic, such. As polypropylene or polyamide, produce and the porous ones and open-pored pipe parts made of an open-pore, extruded plastic, such as B. PP or PE with a preferred porosity of 30 microns to produce, the porosity may vary depending on the application up or down. By are the geometry selection of the individual parts described above Both variants simple and inexpensive to manufacture, the Tool costs can be kept low.

These and other features of preferred embodiments of the invention will become apparent from the claims and from the description and the drawings, wherein the individual features in each case alone or in the form of several Un terkombinen be realized in the embodiment of the invention and other fields and can represent advantageous and protectable versions for which protection is claimed here.

Further Details of the invention will be apparent in the drawing with reference to schematic embodiments described. This shows

1 a section through a suction device according to the invention,

2 an alternative connection possibility of the line parts in enlargement in section,

3 another suction device, also shown in section and

4 also an alternative embodiment of a suction device according to the invention.

description the embodiments

The 1 shows a cross section of a suction device according to the invention. A line section 10 , the suction device, not shown here, has two partial pipe shells 11 on, which via two porous pipe sections 12 connected to each other. The dividing plane is in this case in the flow direction, wherein the two partial pipe shells 11 have a substantially same cross-section. The two subcircuits 11 are here performed air-impermeable, and present in strip form, porous line section 12 has an open-pore structure. At the edges of the partial pipe shells 11 is each a groove 13 arranged in which the strip-shaped, porous line section 12 is inserted and fixed. Through the connection of the two partial sub-shells 11 over the porous line sections 12 the channel-shaped line section results 10 , The partial pipe shells 11 are made of an injection-molded plastic and the porous line section 12 made of an extruded plastic material. In this example, the sections are bonded together via a glued or welded joint. The proportions of the individual line sections to each other can be varied depending on the damping to be set.

The 2 shows a variant of the possibility of attachment of the partial shells of the line section 10 in magnification. Of the 1 corresponding components are provided with the same reference numerals. Again, there are again two substantially air-impervious partial pipe shells 11 over porous pipe sections 12 , which in corresponding grooves 13 in the partial pipe shells 11 are arranged, connected. However, the lower cable part shell has 11 at the end a snap hook 14 which is in a corresponding nose 15 at the end of the upper cable part shell 11 intervenes. The snap hook projects beyond this 14 the height of the porous pipe section 12 , For example, by arranging a plurality of these snap hook connections over the length of the line section 10 In this way, an easy-to-install line section can be produced in a simple manner, which also offers the possibility of replacing the porous line sections 12 To change the damping properties by line sections with a lower or higher porosity.

The 3 shows a further alternative embodiment of the suction device according to the invention in section. The previous figures corresponding components are provided with the same reference numerals. The line section shown here 10 has only one partial line shell 11 and a porous pipe section 12 on. The dividing plane 16 between the two sections also runs parallel to the flow direction. The two sections are at the parting line 16 over connecting surfaces 17 connected with each other. So there is the possibility of the two parts over the connecting surfaces 17 to be connected by an adhesive or welded joint. The cable part shell 11 here has a substantially semi-circular cross-section, wherein the porous pipe section 12 encloses only an angle of about 120 °. Tests have shown that this embodiment of the porous partial pipe shell 12 has positive damping effects in the desired range. In the event of a deviation of the included angle, it is of course also possible to observe a damping effect, so that a desired damping effect can be set via an angular variation. The porous pipe section thus produced 12 can be easily produced by injection molding, but it is also possible, a line section 12 to use, which encloses an angle of 180 °, that has a plate shape, this plate shape can then be produced by extrusion.

The 4 shows a further alternative embodiment of the suction device according to the invention in section. The previous figures corresponding components are provided with the same reference numerals. The line section shown here 10 also has only one partial line shell 11 and a porous pipe section 12 on. A subarea of the subrack 11 is omitted here, either directly in the production or in hindsight by, for example, cut. In this Teilbe rich becomes an acoustic insert 18 introduced, which is clamped in this example, but it can also have a glued or welded connection with the pipe part shell 11 get connected. The acoustic insert 18 consists of a porous material such as PE or PP with an approximate porosity of 30 μm. For clamping the cable part shell has opposite radial abutment edges 19 on which the acoustic insert 18 is hung up. Subsequently, a Warmumlegen two radially outer lands 20 the cable part shell 11 inside the acoustic insert 18 trapped.

Claims (7)

Intake device, in particular for an internal combustion engine, which has a line section for guiding the intake air, wherein the line section is made of several parts, characterized in that at least a part of the line section has a substantially air-impermeable structure and at least one further part of the line section has a porous structure. Intake device according to claim 1, characterized that the division level between the differently structured parts in the flow direction runs. Intake device according to one of the preceding claims, characterized characterized in that the conduit section two substantially impermeable Partial shells, wherein in the separation plane between arranged a strip-shaped porous line section in each case the partial pipe shells is Intake device according to claim 3, characterized that the strip-shaped porous Line section respectively in a correspondingly shaped Groove of the sub-ducts is embedded and the sub-ducts over the stripe porous Line section away by means of a clip connection with each other are connected. Intake device according to one of claims 1 to 2, characterized in that the conduit section a substantially air-impermeable cable part shell and a porous one Parting shell has, wherein the dividing plane axially, ie essentially parallel to the flow direction runs. Intake device according to claim 5, characterized in that that the substantially air-impermeable housing part shell has a U-shaped cross section has and the porous Housing partial shell only an angle between 180 ° and Encloses 120 °. Intake device according to one of the preceding claims, characterized characterized in that the substantially air-impermeable conduit parts injection-molded plastic and the porous pipe parts are made of open-pore are extruded plastic.