DE102004025187B3 - Cooling system for induction manifold of internal combustion engine has tube with fins inside manifold carrying cooling fluid controlled by bimetallic spring valve - Google Patents

Abstract

The cooling fluid tube (4) is doubled back on itself and has an inlet connection (18) and an outlet connection (24) side-by-side. A bimetallic spring (22) moves a valve flap (20) in the inlet connection to control the flow of the cooling fluid. The cooling fluid tube has fins (26) on the outside to improve heat transfer to the air in the channel (13) inside the manifold. The manifold is of rectangular cross-section, and is made of top and bottom half-shells (6,7) joined at a flange.

Description

The The invention relates to an air intake duct system for internal combustion engines with a multi-part housing, in which a collection inlet channel and individual individual intake passages leading to cylinders of the internal combustion engine are formed, wherein the collection inlet channel a cooling section with a cooling device for cooling a recirculated exhaust gas stream having.

Such Luftansaugkanalsystem, in the collecting inlet channel, a cooling device is integrated, is for example in the EP 1 048 839 B1 described. For this purpose, the collection inlet channel is divided into two separate channels, wherein the cooling device is arranged in one of the channels and can be flowed through by an exhaust gas stream. On the housing of the collecting inlet channel Kühlmittelzu- and -abläufe are formed, so that the preassembled heat exchanger element, which is used in this channel section, flows around coolant. Behind the cooling device, the exhaust gas is mixed with the flowing through the main channel of the collecting inlet channel air flow.

adversely on such an embodiment is it that one even distribution between air and exhaust gas flow does not come about, so that under certain circumstances the different single intake ducts with be subjected to a different proportion of exhaust gas. Furthermore, a temperature control of the individual cylinders Guided gas flow to realize only very inaccurate, since first strands the exhaust flow in the air flow and secondly no exact temperature before the cooling device can be determined. The construction and installation of such Execution is due to the high number of parts and difficult accessibility costly and time consuming.

Therefore It is an object of the invention an air intake duct system with a cooler to disposal to provide, at a good mixing of the exhaust gas with the air flow guaranteed is, a temperature control is enabled and assembly and Production costs and expenses compared to known designs be reduced. Furthermore, a further space and component reduction be achieved.

These Task is solved by that the collection inlet channel in the cooling section in cross-section to the flow direction at least into a gas Duct and a coolant leading Channel is divided, and an exhaust gas mass flow controlling exhaust gas inlet device in the flow direction in front of the cooler in the collection inlet channel opens so that at open Abgaseinleitvorrichtung in the at least one gas leading Channel flows an exhaust gas-air mixture. Such an embodiment significantly reduces the number of components and the required space requirement and allows a strands-free Mixing of exhaust and air flow over a longer running distance, so that a Temperature control possible becomes.

In a preferred embodiment shows the case the collection inlet channel an upper and a lower shell, which has an outer jacket the collection inlet channel form, wherein in the cooling section between the upper shell and the lower shell a heat exchanger element is arranged, which with parts of the upper and / or lower shell, the cooling device forms. Thus, upper or lower shell form at least parts of Cooler, so that components be saved. By this arrangement, the assembly of the entire Collecting intake duct system with cooling device due to easy accessibility much easier.

In a continuing Embodiment has the heat exchanger element Ribs which are leading into the gas Project channel and extend substantially in the flow direction. By the ribs will be the heat transfer between the coolant and improves the gas flow, wherein the arrangement of the ribs in the flow direction flow losses be kept minimal.

In another in turn embodiment has the collection inlet channel an air distributor section, in which the collecting inlet channel in branches at least two separate air distribution channels, which in the Upper and lower shell are formed, wherein the cooling device also has corresponding branches and in the Air distribution channels extends. This extends the entire existing cooling section, so that relatively high Temperature differences can be controlled.

In a preferred embodiment is the coolant premier Channel of a closure member, in particular a flap, dominated, which, depending on the position of the closure member ensures a different strong flow through the coolant channel leading and thus a temperature control is feasible. At the same level Exhaust air mixed flow can thus different temperatures can be set.

In a further embodiment, the closure member is a switching flap, which is controlled by a bimetallic spring, where eliminated by additional adjusting devices and the coolant flow is automatically controlled by the voltage applied to the bimetal each temperature.

Preferably the bimetal spring is arranged in the region of a coolant inlet or outlet and of coolant flows around, its temperature thus as a control variable for the position of the switching flap is used. This means that in the cold state of the internal combustion engine as well the coolant corresponds substantially in its temperature to the ambient temperature. In this state, the flap is closed accordingly, so that no cooling he follows. By heating the internal combustion engine heats up also the coolant present in the jacket up to a temperature where the bimetallic spring opens the flap so that the channel now for cooling the exhaust air mixture of coolant flows around becomes. Thus follows with heated internal combustion engine one reliable cooling to use without adjusting devices or a connection to the engine control to have to produce. Otherwise necessary costly adjusting devices can be omitted.

In a preferred embodiment is the heat exchanger element in two-part cross-section, wherein a second housing part a lid is that of coolant perfused Channel, which is formed in a first housing part to the ribs are arranged, at its open side substantially closes. Thus, there is an internal flow of the collecting inlet channel the coolant, whereby a good heat transfer to the flowing around Exhaust gas air mixture takes place and at the same time a simple production of the components For example, in the extrusion or die casting is possible. The open side, with the exception of the coolant inlets and outlets through the lid completely locked.

In a related to this embodiment is the first housing part formed substantially in cross section U-shaped and the legs of the U-shaped Cross section of each coolant flows through being between the legs on one of the two housing parts a partition is arranged, which extends to an end region of the cooler section extends and the first housing part has in each case in the end region of the cooling section a deflection that of coolant flowed through channel on, so that the Legs are flowed through in cross section respectively in the opposite direction. Thus, even with existing branches of the collection inlet channel a single coolant outlet out, so that at least a continuing one Line deleted, whereby the assembly effort is reduced.

In a related to this embodiment are the coolant inlet and the coolant drain arranged side by side in a cross-sectional plane, wherein the connecting piece are formed on the lid and with the interposition of a seal through holes in the lower or upper shell of the collection inlet channel protrude. In such an embodiment are no further connecting pieces on the housing the collection inlet channel necessary and it is omitted hence the transition for the coolant channel between the housing parts the heat exchanger element and the collection inlet channel. additionally is due to the position of the inlet and the outlet to each other the Installation effort reduced.

In another in turn embodiment is in the end areas of the cooling device, which protrude into the air distribution sections, formed a deflection and the partitions between the legs in the area of the branch of the collecting inlet channel run essentially star-shaped together. Despite such a design, which extends into the air distribution channels, remains due to such an arrangement, the production of the heat exchanger element extremely simple and inexpensive, for example, produced by extrusion. This also leads to facilitate the assembly.

In an alternative embodiment is the heat exchanger element executed in two parts in cross section and has a heat exchanger top shell and a heat exchanger lower shell on, wherein the heat exchanger element in the assembled state its periphery is closed, so that in the cooling section between the heat exchanger element and the upper and lower shell of the collection inlet channel of the coolant flowed through channel is formed, which shell-shaped around the heat exchanger top shell and heat exchanger lower shell leading formed gas Channel is arranged. Thus, you can the connecting pieces directly be formed on the upper or lower shell of the collection inlet channel, being through the full Surrounding the gas leading Channel through the coolant leading Channels turn a good heat transfer is ensured. Here, too, assembly and production remain the individual trays simple and inexpensive.

In yet another alternative embodiment, the collecting inlet channel is divided in cross-section to the flow direction in two gas-carrying channels and a coolant-carrying channel, wherein in the gas-carrying channels in the flow direction in front of the cooling device a flap is arranged, which optionally closes one of the gas-conducting channels. Thus, it can be decided via this flap, whether a cooling take place should, by the entire gas flow consisting of exhaust gas flow and air flow is either passed directly to the heat exchanger surfaces or passed into the other channel, so that no cooling takes place, as is desired in the start-up phase. In the warm-up phase is in this embodiment by the non-flow channel good thermal insulation. Depending on the actuator used, it is possible to divert streams into the two channels, so that a temperature control is possible.

In a related to this embodiment is in the cooling section arranged between the upper shell and the lower shell a partition, which flowed through the two gas Channels in the Cross section to the flow direction separates and between the lower shell or the upper shell and the Partition wall is arranged a heat exchanger element, which flowed through the gas Channel partially through the heat exchanger element is formed, from the coolant perfused Channel in cross-section to the flow direction separates, wherein the upper or lower shell in the cooling section an outer shell of the coolant flowed through channel forms. Such a structure has a small number of components and a small volume with good mountability.

In a related to this embodiment surrounds of the coolant flowed through channel flowed through the exhaust Channel in cross-section with the exception of the demarcated by the partition wall Area completely, whereby in this execution a good heat transfer after the warm-up phase and good insulation during the Warm-up phase guaranteed are.

In another in turn embodiment are on the lower shell or the upper shell, which is the outer shell of the coolant perfused Channel forms, at least two connecting pieces for the coolant inlet and the coolant outlet arranged, which in turn therefore used no additional components Need to become.

One Such air intake duct system requires few and easy to mounting components and thus realized on a simple and inexpensive construction a temperature control of the sucked exhaust air mixture, which either continuously or switchable at certain specified temperatures can be done. Such a construction is significantly reducing space in comparison to known systems.

Three embodiments are shown in the drawings and are described below:

1 shows a plan view of a first embodiment of an air intake duct system according to the invention in a sectional view.

2 shows a cross section of this embodiment also in a sectional view.

3 shows a corresponding cross-section, however, in the amount of Kühlmitteleinbeziehungsweise -auslässe.

4 shows a plan view of an alternative Luftansaugkanalsystems invention in a sectional view.

5 shows a cross-section in a sectional view of this alternative embodiment.

6 shows a section in the control of a closure member in side view to the cross section according to 5 ,

7 shows a plan view of another alternative Luftansaugkanalsystems invention.

8th shows a cross section of the embodiment according to 7 along the section line AA.

9 shows a cross section of the air intake duct system according to 7 along the section line BB.

In 1 is a collection inlet channel 1 with two air distribution channels 2 . 3 an air intake duct system, which is a cooling device 4 having, extending over a cooling section 5 the collection inlet channel 1 extends. This cooler 4 is through an upper shell 6 and a lower shell 7 the collection inlet channel 1 and a heat exchanger element disposed therein 8th educated. At the ends of the air distribution channels 2 and 3 each is a flange 9 arranged over which the air distribution channels 2 . 3 can be connected to the rest of the air intake duct system or the adjoining Einzelansaugkanälen not shown. For this purpose, the air distribution channels 2 . 3 one opening at each end 10 . 11 on, over which the fluidic connection of Luftervertei lerkanäle 2 . 3 , is manufactured to the single intake ducts. Into the collection inlet channel 1 flows through a suction port 12 an exhaust air-air mixture, so that in front of the intake opening 12 a Abgaseinleitvorrichtung, not shown, and optionally a throttle valve are arranged.

The collection inlet channel 1 is through the use of the heat exchanger element 8th into a gas channel 13 and a coolant channel 14 divided, it can be seen from the drawing that the coolant channel leading 14 also into the air distribution channels 2 . 3 extends and has a flow and return. This means that each one in one end 16 the heat exchanger element 8th a diversion 17 the coolant flow is present, so that now flows in the next direction in Strömungsrichtrung the coolant in the opposite direction. The arrangement with flow and return it is possible a coolant outlet 24 seen directly in the flow direction next to a coolant inlet 18 train.

The coolant inlet 18 is by a closure member, which here as a switching flap 20 is formed, dominated, which is driven by an adjusting device, in the present embodiment as a simple bimetallic spring 22 is trained.

The structure of this collection inlet channel 1 gets more accurate from the 2 and 3 seen, which has a cross section to the collecting inlet channel 1 of the 1 represent, wherein the cross section of the 2 seen in the gas flow direction immediately behind the coolant fluid inlet 18 or coolant liquid outlet 24 located and the cross section according to 3 Seen in the same flow direction is located in front of the cooling section.

In the figures it can be seen that the heat exchanger element 8th between the upper shell 6 and the lower shell 7 the housing of the collection inlet channel 1 over ribs 26 , which extend over the entire outer circumference of the heat exchanger element 8th extend, is fixed. More, slightly shorter ribs 26 are also for better heat transfer at the heat exchanger element 8th formed, which in turn consists of a first U-shaped housing part 28 and one this u-shaped part 28 closing lid 30 consists. On the first housing part 28 , which can be executed as a die-cast part, is a partition in cross-section 32 leading between the flow and the return coolant forming channel 14 arranged. Accordingly, this partition 32 in the end area 16 or in the area of diversion 17 not trained. The partition 32 runs in the illustrated embodiment approximately at the end of the collection inlet channel 1 in front of the air distribution sections 2 . 3 approximately star-shaped together to ensure the separation between the flow and return in the two legs of the U-shaped part.

In 3 are also the two connecting pieces 33 . 34 for the inlet 18 or the coolant outlet 24 shown. These are integral with the lid 30 formed and protrude through appropriate openings 36 . 38 in the lower shell 7 the collection inlet channel 1 therethrough. Accordingly, it is necessary in this area the gas channel leading 13 relative to the environment by two seals designed as O-rings 40 . 42 seal.

The operation of the present Luftansaugkanalsystems is such that after the start of the internal combustion engine air via the throttle and exhaust gas via the Abgaseinleitvorrichtung to the intake 12 arrives. From here, the exhaust air-air mixture flows into the cooling section 5 , wherein in cold combustion engine, the switching flap 20 is closed, so that no coolant flows. Due to the warm exhaust gas in the exhaust air flow, the coolant in the legs of the exhaust gas cooling device 4 heated quickly so that the Bimemtallfeder 22 , which also, like from the 2 and 3 can be seen in the coolant channel leading 14 is arranged, is actuated and the switching flap 20 automatically opens. As a result, now a coolant through the channel 14 flow, so that the exhaust gas-air mixture in the following, so after heating of the coolant and the catalyst of the internal combustion engine, is cooled. While the exhaust air flow through the intake 12 and the cooling section 5 to the openings 10 . 11 the air distribution channels 2 . 3 flows, flows with the switching flap open 20 the coolant flow from the inlet 18 over the diversions 17 in the end areas 16 back to the coolant outlet 24 ,

In the 4 to 6 a further embodiment is shown, wherein the basic structure of the collecting inlet channel 1 and the adjoining air distribution channels 2 . 3 with the cooling device 4 remains substantially the same and the same reference numerals are used accordingly for the same parts. The main difference to the first embodiment is in particular from the 5 showing the cross section of such a system, clearly. The heat exchanger element 8th consists here of a heat exchanger top shell 44 and a heat exchanger lower shell 46 which are made substantially the same, wherein the ribs 26 facing each other and after laying one on top of the heat exchanger shell 44 with the heat exchanger lower shell 46 a closed space is formed within these shells. Accordingly, the outer ribs 26 the longest and designed to hold together via a welded or glued joint.

Through this heat exchanger element 8th will also be a gas leading channel 13 from a coolant channel 14 separated, being here the coolant channel leading 14 between the housing top shell 6 and the housing lower shell 7 the collection inlet channel 1 and the heat exchanger element 8th is formed. Between these two flows the coolant, so that between the two heat exchanger shells 44 . 46 formed space the gas channel leading 13 forms, passing through the coolant channel 14 is surrounded completely shell-shaped. The control of the refrigerant flow switching flap 20 is also here by a bimetallic spring 22 pressed, which in a room 48 is arranged, over a channel 50 with the inlet pipe 33 is fluidically connected. The used spring 22 is not executed here as in the first embodiment as a bar spring, but as a torsion spring, the operation remains essentially the same.

In such an embodiment, however, compared to the first embodiment, it is necessary to use a second unillustrated coolant outlet, if the cooling device 4 into the air distribution channels 2 . 3 extends and no deflection is provided. Thus, here the flow direction of the gas flow corresponds to the flow direction of the coolant. For the rest, the operation corresponds to that of the first embodiment.

The 7 to 9 show a third embodiment, wherein the construction of the heat exchanger element 8th like out 8th now visible only from a heat exchanger shell 46 and a partition 54 which consists of the gas channel 13 now in two channels 13 and 13 ' separates. The coolant flows in the present embodiment only between the lower shell 7 the collection inlet channel 1 and the lower shell 46 the heat exchanger element 8th so that the ribs too 26 only in one of the two gas channels 13 protrude into it. In comparison to the previous exemplary embodiments, the temperature control no longer takes place via a switching flap arranged in the coolant region 20 but via a controllable flap 56 which is arranged so that either the inlet to the gas channel 13 or to the gas channel 13 ' is interrupted in whole or in part. Thus, with still cold internal combustion engine, only the channel 13 ' flows through and at fully heated internal combustion engine, the channel 13 between the partition 54 and the heat exchanger lower shell 46 , Also intermediate positions are possible when using appropriate adjusting devices. As an actuator 58 for the flap 56 come both pneumatic actuator and electromotive actuators in question, in the present embodiment, a pneumatic actuator 58 was chosen in the form of a vacuum box.

The partition 54 is between the two shells 6 . 7 of the collection inlet channel 1 attached. The heat exchanger lower shell 46 is on the partition 54 attached, which thus serves as a cover for the gas channel 13 serves, while maintaining a fluid-tight separation between the gas channel 13 ' and the coolant channel 14 is available. How out 9 will be apparent is the flap 56 over a jewel 60 which is in the lower shell 7 is inserted and by placing the upper shell 6 is attached, stored.

By such designs will it be possible on extremely small space a reliable integrated exhaust gas cooling and thus to carry out temperature control of the internal combustion engine. The in the embodiments shown heat exchanger elements are for example in diecasting or continuous casting and thus cost-effective manufacture. A simple assembly is due to the special structure guaranteed with the different shells. Through the lan gen flow paths the mixture is also a strandsfreie Mixing of the exhaust and the air flow ensured.

It it becomes clear that different types versions and modifications of such Luftansaugkanalsystems invention possible are, depending on the structure of the air intake duct system with distribution channels and / or Einzelansaugkanälen the length the used cooling section must be adapted and possibly extend into the Einzelansaugkanäle may or may end with the collection inlet channel. Furthermore, you can also depending on the used adjusting devices different desired temperatures be set in the air intake duct system, in the example the existing switching flaps as continuously adjustable flaps accomplished become. Also, the attachment of the heat exchanger elements in Sammeleinlaßkanalsystem can be done in different ways, for example through different ones welding processes or optionally by gluing and fitting the facing each other surfaces the individual components. Likewise, the heat exchanger elements executed differently become what is clear from the different embodiments.

Claims (16)

An air intake duct system for internal combustion engines with a multi-part housing in which a collecting inlet channel and individual to intake manifolds of the internal combustion engine Einzelansaugkanäle are formed, wherein the collecting inlet channel has a cooling section with a cooling device for cooling a recirculated exhaust gas stream, characterized in that the collection inlet channel ( 1 ) in the cooling section ( 5 ) in cross-section to the flow direction at least in a gas-carrying channel ( 13 ) and a coolant channel ( 14 ), and an exhaust gas mass flow controlling Abgaseinleiteinrichtung in the flow direction in front of the cooling device ( 4 ) into the collection inlet channel ( 1 ) so that when the exhaust gas inlet device in the gas leading channel ( 13 ) flows an exhaust gas-air mixture. Air intake duct system according to claim 1, characterized in that the housing of the collecting inlet duct ( 1 ) an upper shell ( 6 ) and a lower shell ( 7 ), which an outer jacket of the collecting inlet channel ( 1 ), wherein in the cooling section ( 5 ) between the upper shell ( 6 ) and the lower shell ( 7 ) a heat exchanger element ( 8th ) which is arranged with sections of the upper shell ( 6 ) and / or the lower shell ( 7 ) the cooling device ( 4 ). Air intake duct system according to claim 2, characterized in that the heat exchanger element ( 8th ) Ribs ( 26 ) leading into the gas channel ( 13 ) and extend substantially in the direction of flow. Air intake duct system according to one of the preceding claims, characterized in that the collecting inlet duct ( 1 ) has an air distribution section in which the collecting inlet channel ( 1 ) into at least two separate air distribution channels ( 2 . 3 ) branches, which in the upper shell ( 6 ) and the lower shell ( 7 ) are formed, wherein the cooling device ( 4 ) also has corresponding branches and into the air distribution channels ( 2 . 3 ). Air intake duct system according to one of the preceding claims, characterized in that the coolant-carrying duct ( 14 ) of a closure member ( 20 ), in particular a flap, is mastered. Air intake duct system according to claim 5, characterized in that the closure member ( 20 ) is a switching flap, which of a bimetallic spring ( 22 ) is controlled. Air intake duct system according to claim 6, characterized in that the bimetallic spring ( 22 ) in the region of a coolant inlet ( 18 ) or a coolant outlet ( 24 ) is arranged and flows around coolant. Air intake duct system according to one of claims 2 to 7, characterized in that the heat exchanger element ( 8th ) is designed in two parts in cross-section, wherein a second housing part ( 30 ) is a lid, the channel through which coolant flows ( 14 ), which in a first housing part ( 28 ) is formed, on which the ribs ( 26 ) are arranged, on its open side substantially closes. Air intake duct system according to claim 8, characterized in that the first housing part ( 28 ) is formed substantially in cross-section U-shaped and the legs of the U-shaped cross-section each coolant are flowed through, wherein between the legs on one of the two housing parts ( 28 . 30 ) a partition wall ( 32 ), which extends to one end region ( 16 ) of the cooling section ( 5 ), and the first housing part ( 28 ) in each case in the end region ( 16 ) of the cooling section ( 5 ) a diversion ( 17 ) of the coolant leading channel ( 14 ), so that the legs are flowed through in cross section in each case in the opposite direction. Air intake duct system according to claim 8 or 9, characterized in that the coolant inlet ( 18 ) and the coolant outlet ( 24 ) are arranged side by side in a cross-sectional plane, wherein the connecting pieces ( 33 . 34 ) on the lid ( 30 ) are formed and with the interposition of a seal ( 40 . 42 ) through holes ( 36 . 38 ) in the upper shell ( 6 ) or the lower shell ( 7 ) of the collection inlet channel ( 1 ) protrude. Air intake duct system according to one of claims 9 to 10, characterized in that in the end regions ( 16 ) of the cooling device ( 4 ) entering the air distribution sections ( 2 . 3 ), in each case the deflection ( 17 ) is formed and the partitions ( 32 ) between the legs in the region of the branch of the collecting inlet channel ( 1 ) Run substantially star-shaped together. Air intake duct system according to one of claims 2 to 7, characterized in that the heat exchanger element ( 8th ) is designed in two parts in cross-section and a heat exchanger upper shell ( 44 ) and a heat exchanger lower shell ( 46 ), wherein the heat exchanger element ( 8th ) is closed in the assembled state over its circumference, so that in the cooling section ( 5 ) between the heat exchanger element ( 8th ) and the upper shell ( 6 ) and lower shell ( 7 ) of the collection inlet channel ( 1 ) the coolant-carrying channel ( 14 ), which shell-shaped around the heat exchanger shell ( 44 ) and heat exchanger lower shell ( 46 ) formed gas channel ( 13 ) is arranged. Air intake duct system according to one of claims 1 to 4, characterized in that the collecting intake duct ( 1 ) in cross-section to the flow direction in two gas-carrying channels ( 13 . 13 ' ) and a coolant channel ( 14 ) under is shared, where in the gas-carrying channels ( 13 . 13 ' ) in the flow direction in front of the cooling device ( 4 ) a flap ( 56 ), which optionally has one of the gas-carrying channels ( 13 . 13 ' ) closes. Air intake duct system according to claim 13, characterized in that in the cooling section ( 5 ) between the upper shell ( 6 ) and the lower shell ( 7 ) of the collection inlet channel ( 1 ) a partition wall ( 54 ) which houses the two gas-carrying channels ( 13 . 13 ' ) in cross section to the flow direction and between the lower shell ( 7 ) or the upper shell ( 6 ) and the partition ( 54 ) a heat exchanger element ( 8th ), which channels the gas ( 13 ) partially through the heat exchanger element ( 8th ) is formed by the coolant-carrying channel ( 14 ) in cross-section to the flow direction, wherein the upper shell ( 6 ) or the lower shell ( 7 ) in the cooling section ( 5 ) an outer jacket of the coolant-carrying channel ( 14 ). Air intake duct system according to claim 14, characterized in that the coolant flow channel ( 14 ) the gas channel ( 13 ) in cross-section, except through the partition wall ( 54 ) completely encloses the delimited area. Air intake duct system according to one of claims 13 to 15, characterized in that on the lower shell ( 7 ) or the upper shell ( 6 ), which flows through the outer jacket of the coolant flow channel ( 14 ), at least two connecting pieces ( 33 . 34 ) are arranged for the coolant inlet and the coolant outlet.