DE102018100636A1 - Gas flow conducting valve - Google Patents

Abstract

The invention relates to a gas flow conducting valve (1), comprising a valve housing (2) and a displaceably mounted and at least partially within the valve housing (2) arranged valve body (3). In this case, the valve (1) on a cam mechanism (4), said cam gear (4) with the valve body (3) is operatively connected, so that the valve body (3) by a driven side on the cam gear (4) adjacent output adjustment movement (5) becomes.

Description

The invention relates to a gas flow conducting valve, which has a valve housing and a displaceably mounted and at least partially disposed within the valve housing valve body.

To reduce the present in the exhaust of an internal combustion engine of a motor vehicle pollutants such as solid particles, unburned hydrocarbons, nitrogen oxides or carbon monoxide complex exhaust systems are usually used, which are characterized by an interaction of multiple catalysts, exhaust gas recirculation systems and exhaust gas turbochargers.

As a rule, catalysts such as oxidation catalysts, NOx storage catalysts and / or SCR catalysts are arranged downstream of an exhaust gas turbocharger in order to exploit the prevailing flow rate of the exhaust gas for the exhaust gas turbocharger. However, this and, for example, an upstream urea injection for an SCR catalytic converter have the consequence that the temperature of the exhaust gas drops and as a result the exhaust gas purification by the catalyst system used does not take place in an optimal manner, especially in cold start situations.

For this reason, it makes sense to use, for example, another NOx storage catalytic converter upstream of the exhaust-gas turbocharger, which, if required, in particular in cold-start situations, is switched into the exhaust gas line and thereby reduces pollutant emissions. In order to prevent excessive aging in different operating conditions of the engine and in the worst case even destruction of the catalyst, at the operating temperature of the exhaust-producing internal combustion engine and associated high exhaust gas temperatures, it is necessary that this catalyst is at least partially separated from the exhaust line. This is realized with one or more exhaust gas conducting valves.

The DE 10 2015 214 072 A1 shows such a valve for conducting a gas flow, by means of which the gas flow between a main branch and a secondary branch can be partially or completely passed. In one embodiment it is provided that a catalytic converter is arranged in the secondary branch, which is used in particular in a cold start phase of an internal combustion engine for reducing the exhaust gases generated by the internal combustion engine. When temperatures exceeding catalytic converter temperatures are exceeded, the exhaust gas flow can be partially or completely disconnected from the catalytic converter and the exhaust gas can be passed virtually undisturbed through the main branch of the valve. For the switching operation in this case an actuation of the valve or the valve spool, for example, by an actuator, necessary.

Against this background, the invention has the object, a valve of the type mentioned in such a way that a possible close to the engine arrangement of the valve is made possible by a compact executed actuation of the valve body of the valve.

This object is achieved with a valve according to the features of claim 1. The dependent claims relate to particularly expedient developments of the invention.

According to the invention, therefore, a gas flow, for example an exhaust gas flow, is provided, which has a valve housing, in particular with a flow main branch and a flow secondary branch and a valve body, for example, displaceably mounted between two Verschubendpositionen and at least partially disposed within the valve housing. Furthermore, the valve is designed such that it has a cam gear and this cam gear, z. B. indirectly or directly, is operatively connected to the valve body, so that the valve body is displaced by an output side adjacent to the cam gear output driving movement and / or is displaceable. In this case, the displacement of the valve body is in particular a longitudinal displacement. The arrangement of a cam gear, which is designed in particular as a spatial cam gear, on or in the immediate vicinity of the valve has the advantage that an extremely compact operation of the valve and thus an extremely compact valve may be present, which has a low space requirement. This is particularly important in the arrangement of the valve in the exhaust system of an internal combustion engine of a motor vehicle with correspondingly low space resources of great importance.

The valve body slidably disposed in the valve housing of the valve should consist of a longitudinal element and a transverse element per se for guiding the gas flow, wherein the cross slide should be formed on the front side of the longitudinal element such that the valve body has a T-shaped longitudinal section.

The flow main branch of the valve may consist essentially of a main flow channel, whereas the flow secondary branch should be formed essentially of two secondary flow channels. These bypass ducts should open on one side into the main flow channel. At the Strömungssebenzweig can be flowed through by a gas flow component, such as for example, a catalyst may be arranged. In this case, a first of the secondary flow channels would serve the inflow of the gas stream to and a second of the secondary flow channels to the outflow of the gas stream from the component to be flowed through. In this case, the gas flow in response to a Verschubposition of the valve body should be completely, partially or not from the flow main branch in the Strömungssebenzweig passed and respectively, not, partially or completely flow through the main flow branch. The valve body can in this case assume an arbitrary displacement position between and including the Verschubendpositionen.

To effect the output side adjacent to the cam gear output driving movement on the drive side a drive actuating movement is necessary, which is introduced into the cam gear. This drive actuating movement can be provided in particular by an actuator, it being conceivable that the drive actuating movement is linear or rotationally pronounced.

In the case of a rotary drive actuating movement, for example, there is the possibility that a rotational movement generated by a motor and this rotational movement by means of a functionally connected to the motor and the cam gear, another transmission, such. As a gear transmission, transmitted to the cam gear and is introduced into this as a drive actuator movement. The engine can be used as an electric motor, in particular z. Example, as a servo motor, executed.

In a particularly advantageous embodiment of the invention, the cam mechanism between two end stop positions with an included angle greater than a zero angle and smaller than a full angle, the angle may be in particular an acute angle, a right angle or an obtuse angle, rotatably formed and / or it turns by rotation of the cam gear between the two end stop positions a maximum longitudinal displacement of the valve body between the two Verschubendpositionen. Due to the fact that the valve body only between two Verschubendpositionen, z. B. in response to a load condition or a cold start of an internal combustion engine to be moved, the cam mechanism is subject in operation no continuous rotational movement, but only positioning movements, which can differ in their travel, the duration and the adjustment direction. A maximum adjusting movement here comprises an adjusting movement from a first of the end stop positions to a second one of the end stop positions, this maximum adjusting movement causing the maximum longitudinal displacement of the valve body in the valve housing.

An additionally extremely profitable embodiment of the invention is characterized in that the cam mechanism is arranged on the valve housing, whereby a very compact design of the valve can be produced. The cam gear should be arranged correspondingly on one of the housing sides, which has no flow openings of the flow main branch and / or the flow secondary branch.

An embodiment of the invention in that on the cam gear on the drive side at least one push rod and / or at least one crank handle is arranged, via which a linear drive actuating movement can be introduced into the crank mechanism, turns out to be so promising that thereby a simple, inexpensive and error-resistant transmission mechanism is provided, by means of which the linear drive actuating movement can be introduced into the cam gear. The push rod and / or the crank handle put the linear drive actuating movement in a rotary motion of the cam gear. The linear drive actuating movement should in turn be provided by an actuator. In this actuator, it may be a linear drive, such. As an electrodynamic linear motor or a linear actuator act. Also conceivable are pneumatic cylinders or in particular a vacuum box which is operated with the negative pressure generated by an internal combustion engine in the intake tract.

Another promising embodiment of the invention is given when the cam gear has a cam carrier in the form of a rotatably mounted cam and / or the cam of the cam gear is flat and circular. Due to the planar design, the space taken up by the cam mechanism can be profitably reduced to a minimum, and moreover, such a flat, circular cam can be produced extremely inexpensively.

Also, an advantageous development of the invention is due to the fact that in the cam at least one cam the cam is partially recessing groove formed and / or slidably disposed in the groove track of the cam at least part of a Abgriffsgliedes the cam gear. Due to the engagement of the Abgriffsgliedes in the groove track of the cam, the Abgriffsglied undergoes a shift in accordance with a straight line of the Abgriffsgliedes. In order to enable the engagement of the tapping member in the groove track and the longitudinal displacement of the valve body, in the valve or the valve housing an opening, for example a slot should be formed.

An embodiment of the invention also presents itself as having an advantage when the groove track is formed with an inconstant curvature along a curved section positioned acentrically in the cam disk. In this case, it should be provided that the curvature increases from the center of the next point of the curve section or the groove track to the point of the curve section or groove track that is furthest from the center in the radial direction.

In addition, if a respective direction of movement of the drive actuating movement and the output setting movement in the plane of the cam or is formed parallel to the plane of the cam, the directions of movement are not parallel to each other, so also contributes to increased reliability, compact design and cost-effective production of Valve at. Accordingly, it is conceivable that an acute angle, a blunt or obtuse angle or preferably a right angle is present between the directions of movement of the drive actuating movement and the output setting movement, but not a zero angle or an extended angle. Naturally, the direction of the output drive movement would be parallel or even coaxial with the longitudinal direction of the valve body in order to allow a displacement of the valve body.

In a very practical embodiment of the invention, the Abgriffsglied is formed on the valve body, for example in the form of a one-piece design, or it is, in particular indirectly or directly, arranged on the valve body and / or the Abgriffsglied is in the form of a pin. Thus, in a structurally advantageously simple manner, the output setting movement can be transmitted to the valve body. Necessarily, the valve body would be mounted at least in a linear guide, for example in a plain bearing or more plain bearings, to allow a displacement of the valve body due to the transmission of the driven adjusting movement. The straight guide of the tapping member would be realized in this case via the valve body or the linear guide of the valve body. It is also to be regarded as promising if the cam mechanism has a cover element, for example a cover, which is arranged at least partially, in this case at least one side, normal to the disk plane and radially surrounding the cam and / or the cam is rotatably mounted within the cover. In an arrangement of the cam on the valve body of the valve, it turns out to be practical when the cover or the cam is mounted in conjunction with the cover so on the valve body, that the cover is arranged facing away from the valve body. The cam would thus be completed on one side of the cam through the cover to the environment, which on the one hand to avoid interference by external influences and on the other hand, the cover can fulfill a sealing function.

To transmit the drive actuating movement on the cam of the cam gear, for example by means of the push rod and / or the crank, it would be useful to connect the cam via a centrally arranged shaft with the push rod and / or the crank, where it would be considered as practical, in addition the arrangement of a seal in the edge region of the cover also between the cover and valve body a seal, in particular a hollow cylindrical sealing bush to provide between the shaft and the cover. The cover and the seal by means of the seals against the shaft and / or the valve body can advantageously prevent leakage of gases of the gas stream, in particular exhaust gas of an internal combustion engine, or at least largely minimize.

• 1 eine Darstellung einer Weiterbildung des erfindungsgemäßen Ventils;
• 2 eine weitere Darstellung einer erfindungsgemäßen Weiterbildung des Ventils.

The invention allows numerous embodiments. To further clarify its basic principle, one of them is shown in the drawing and will be described below. This shows in

• 1 a representation of a development of the valve according to the invention;
• 2 a further illustration of an inventive development of the valve.

1 shows a schematic representation of a development of the invention, a gas flow conducting valve 1 , The valve 1 in this case has the valve housing 2 and the slidably mounted and within the valve housing 2 arranged valve body 3 on. The valve body 3 consists of the longitudinal element 15 and the cross member 16 , The valve 1 and here the valve housing 2 have the main flow branch 17 and the flow secondary branch 18 , which in conjunction with the valve body 3 the direction of the through the valve 1 Serve flowing gas stream. The valve 1 also has the cam gear 4 on which on the valve body 2 is arranged. Here is the cam gear 4 such with the valve body 3 connected, that this at the output side of the cam gear 4 adjacent output drive movement 5 the longitudinal displacement L experiences. The cam mechanism 4 has a cam carrier in the form of the rotatably mounted cam 11 on, with this cam 11 is flat and circular, partially of the cover 14 is enclosed and within the cover 14 is arranged rotatably mounted. Furthermore, the cam is 11 arranged aligned with the valve housing that the plane of the cam 11 the valve housing 2 is facing. In the cam 11 is also the Nutenbahn 12 formed, wherein in the groove track 12 a part of the tapping member 13 of the cam gear 4 slidably disposed, respectively in the track 12 intervenes. The tapping member 13 is on the valve body 3 formed and thus the valve body 3 with the cam gear 4 over the tapping member 13 operatively connected. The Nutenbahn 12 itself is along one in the cam 11 acentrically positioned curve portion formed with inconstant curvature. The valve body 3 is in the representation in its second Verschubendposition 7b , in which on the one hand the flow secondary branch 18 is closed and this Verschubendposition 7b by turning the cam gear 4 respectively the cam 11 in the second end stop position 6b results. If, however, a rotation of the cam gear 4 respectively the cam 11 in the first end stop position 6a , the valve body shifts 3 due to the curvature of the groove track 12 in his first Verschubendposition 7a , This shift can be supported by a restoring force of a restoring element not shown or even done. In the cam mechanism 4 is the trained as a vacuum box actuator 19 the linear drive actuator movement 10 introduced, wherein the respective direction of movement of the drive actuating movement 10 and the output drive movement 5 parallel to the plane of the cam 11 is formed, wherein the directions of movement are not formed parallel to each other, but include a right angle with each other.

In 2 is another schematic view of the valve 1 shown, which again the arrangement of the cam gear 4 on the valve body 2 represents. The on the valve housing 2 of the valve 1 arranged cam mechanism 4 also has the in 1 illustrated cam 11 on which of the cover 14 on the valve body 2 opposite side of the cam 11 enclosed and thus protected against environmental influences. In addition, no gas from the inside of the valve 1 respectively the valve housing 2 escape into the environment. Furthermore, the illustration shows the drive-side arrangement of the push rod 8th and the multi-part crank 9 , about which the linear drive actuating movement 10 is introduced into the crank mechanism. This is the push rod 8th with the crank 9 over a swivel and the push rod 8th with the actuator 19 connected. The through the crank 9 in a rotary motion converted linear drive actuating movement 10 gets over the crank 9 on the with the cam 11 connected shaft 20 transfer. To avoid gas leakage from inside the valve 1 is between the shaft 20 and the cover member 14 the seal 21 arranged in the form of a sealing bush.

LIST OF REFERENCE NUMBERS

1

Valve

2

valve housing

3

valve body

4

cam gear

5

Driven adjusting movement

6a, 6b

end stop

7a, 7b

Verschubendposition

8th

pushrod

9

crank

10

Drive actuating movement

11

cam

12

Nutenbahn

13

Abgriffsglied

14

cover

15

longitudinal member

16

crossmember

17

Flow main branch

18

Flow auxiliary branch

19

actuator

20

wave

21

poetry

L

along shift

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102015214072 A1 [0005]

Claims (10)

Gas flow conducting valve (1), comprising a valve housing (2) and a slidably mounted and at least partially within the valve housing (2) arranged valve body (3), characterized in that the valve (1) has a cam mechanism (4) and this cam mechanism (4) is operatively connected to the valve body (3), so that the valve body (3) by a driven side on the cam gear (4) adjacent output adjustment movement (5) is moved. Valve (1) to Claim 1 , characterized in that the cam gear (4) between two Endanschlagspositionen (6a, 6b) is formed with an included angle greater than a zero angle and smaller than a full angle rotatable and / or by rotation of the cam gear (4) between the two end stop positions ( 6a, 6b) sets a maximum longitudinal displacement (L) of the valve body (3) between its two Verschubendpositionen (7a, 7b). Valve (1) after the Claims 1 or 2 , characterized in that the cam mechanism (4) is arranged on the valve housing (2). Valve (1) according to at least one of the preceding claims, characterized in that on the camshaft (4) on the drive side at least one push rod (8) and / or at least one push crank (9) is arranged, via which a linear drive actuating movement (10) in the Crank mechanism can be introduced. Valve (1) according to at least one of the preceding claims, characterized in that the cam gear (4) has a cam carrier in the form of a rotatably mounted cam disc (11) and / or the cam disc (11) of the cam gear (4) is flat and circular , Valve (1) according to at least one of the preceding claims, characterized in that in the cam disc (11) at least one cam plate (11) partially ausnehmende groove track (12) is formed and / or in the groove track (12) of the cam disc (11) at least a part of a Abgriffsgliedes (13) of the cam mechanism (4) is arranged displaceably. Valve (1) according to at least one of the preceding claims, characterized in that the groove track (12) along an in the cam (11) acentrically positioned curve portion is formed with inconstant curvature. Valve (1) according to at least one of the preceding claims, characterized in that a respective direction of movement of the drive actuating movement (10) and the output setting movement (5) in the plane of the cam (11) or is parallel to the plane of the cam (11) , wherein the directions of movement are not formed parallel to each other. Valve (1) according to at least one of the preceding claims, characterized in that the Abgriffsglied (13) on the valve body (3) is formed or arranged on the valve body (3) and / or the Abgriffsglied (13) is in the form of a pin , Valve (1) according to at least one of the preceding claims, characterized in that the cam mechanism (4) has a cover element (14) which surrounds the cam disc (11) at least partially surrounding and / or the cam disc (11) within the cover element (14 ) Is arranged rotatably mounted.

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