WO2024069467A1

WO2024069467A1 - A method for actuation diagnosis of a control assembly, in particular a control assembly for swirl valves

Info

Publication number: WO2024069467A1
Application number: PCT/IB2023/059604
Authority: WO
Inventors: Paolo Maria MAGHINI; Michele DURANTI; Lara VALESANI; Jessica ACCARINO; Riccardo LODI; Luca BOTTIGLIERO
Original assignee: Stellantis Europe S.P.A.
Priority date: 2022-09-27
Filing date: 2023-09-27
Publication date: 2024-04-04

Abstract

There is described a method for actuation diagnosis of a control assembly (SW), in particular a control assembly for swirl valves (4), Wherein the control assembly (SW) comprises a mobile unit (2, 4), an actuator (6) operatively connected to said mobile unit (2, 4) to control a movement thereof along an actuation coordinate, and an actuation diagnosis system (10) comprising a warning element (12) connected to said mobile unit (2) and integral with said mobile unit (2) in a movement along the actuation coordinate, and one or more abutment elements (14, 16) configured for limiting the movement of the warning element (12) along the actuation coordinate upon the occurrence of a contact with the same warning element (12), the method comprising: controlling a movement of the mobile unit (2) along the actuation coordinate, wherein the movement of the mobile unit (2) comprises an extension at least partially limited by said one or more abutment elements (14, 16), detecting an anomaly condition in the movement of the mobile unit (2), said anomaly condition comprising at least one of an anomaly condition in an interaction between said one or more abutment elements (14, 16) and the warning element (12), and an anomaly condition in negotiating said extension.

Description

A method for actuation diagnosis of a control assembly, in particular a control assembly for swirl valves

TEXT OF THE DESCRIPTION

Field of the Invention

The present invention relates in particular to internal combustion engines . The invention was developed with reference to the actuation diagnosis of control assemblies installed on internal combustion engines , with speci fic reference to a control assembly for swirl valves .

Prior Art

Figures 1 to 6 annexed to the present description illustrate the prior art which constitutes a reference for the development of the present invention, illustrating therefore the technical problems thereof as well .

Reference number 1 in Figure 1 generally denotes a head for an internal combustion engine . As is generally known, in the internal combustion engine the head 1 surmounts a crankcase wherein one or more engine cylinders are present ; moreover, the head 1 comprises one or more flame decks , at the positions of the cylinders , which define therewith the engine combustion chambers . With reference to Figures 1 and 2 , the head 1 has pairs of intake conduits IC, which terminate into the respective flame deck, or generally into a respective combustion area of the head, and wherein intake valves are located for the phased supply of the combustion air to the engine . One of the conduits IC of each pair is a spiral-shaped conduit , and as a consequence it is configured to impart a helical movement to the combustion air entering the cylinder . The other conduit of the pair is a conduit having a so- called "tumbling" geometry, and it is associated with a control assembly SW comprising a shaft 2 rotatable about an axis X2 and a throttle valve 4 ( or "swirl valve" ) fitted onto shaft 2 and rigidly rotatable therewith about axis X2 .

The shaft 2 is common to all the pairs of conduits IC, and runs along the wall of head 1 whereat there are located the ends of the conduits IC which are opposite to the ends on the flame deck, while the valves 4 are longitudinally spaced along the axis X2 and are individually associated with the plunger-type conduits IC ; therefore , there is provided one valve 4 for each plunger-type conduit IC, and said valve is always located at the wall of head 1 where there are arranged the ends of the conduits IC opposite the ends on the flame deck . Figure 1 shows , albeit partially in section, an intake mani fold MF having rotation bearings for the shaft 2 .

In a way known per se , the position of the swirl valve 4 leads to modulating the swirl motion of the combustion air entering the cylinder . A completely open valve 4 does not bring about any meaningful partiali zation of the flow of combustion air into the plunger-type conduit IC, and therefore the flow of air entering the cyl inder will mainly flow in the plungertype conduit ; consequently the flow through the spiralshaped conduit will be smaller and will therefore have a lower speed . This means that the swirl motion in the cylinder will globally be less energi zed and less developed . On the contrary, a valve 4 in a position nearly closing ( occluding) the associated conduit IC partiali zes the air flow entering the plunger-type conduit , so that the air f low entering the cylinder will mainly pass through the spiral-shaped conduit IC, with a consequent increase of the speed of the air entering the cylinder through the spiral-shaped conduit IC and a stronger energizing of the swirl motion.

With reference to Figures 3 to 6, they schematically show some known examples of the control assembly SW. In all the Figures, reference 6 denotes an actuator element (e.g., an electric motor) , whereas number 8 denotes a coupling between the actuator 6 and the shaft 2, having the double function of transmitting motion and compensating the tolerances of the power train. The actuator 6 may correspond to a variety of known actuators, including rotary actuators and linear actuators, whether or not they are equipped with an autonomous position detecting system (e.g., an encoder within a rotary electric motor) .

The various configurations shown in the examples of Figures 3 to 6 depend on the geometry of the engine to which the system SW is associated, because depending on such geometry each of the various configurations may be more convenient than others.

In Figure 3, the coupling 8 is a direct connection arranged between the actuator 6 (a rotary electric motor) and the shaft 2. In Figure 4, the coupling 8 is a gearing comprising (by way of example) a driven wheel 8A rotatably connected to the shaft 2 and a driving wheel 8B rotatably connected to a rotor of the actuator 6.

In Figure 5, the coupling 8 includes a first crank 8A which is rotatably connected to the rotor of the actuator 6, a rod 8B which is pivotally connected, at an end thereof, to the crank 8A and, at a second end thereof, to a second crank 8C, which in turn is rotatably connected to the shaft 2.

Generally speaking, it must be borne in mind that the coupling 8 of the Figures 4, 5 may be positioned at a location different from the location suggested by the Figures . Speci fically, the Figures show a positioning of the coupling 8 at an end of the shaft 2 ; however, it is possible to arrange it in the middle or in other positions along the shaft 2 . This is true both for the solution in Figure 4 and for the solution in Figure 5 . An exception is the solution in Figure 3 , because the direct coupling ( e . g . , an Oldham coupling) requires to be mounted at the end of the shaft 2 .

Figure 6 , which is valid for any exemplary embodiment of the control assembly SW, schematically shows a system for actuation diagnosis of a known type . The diagnosis system comprises an angular position sensor PS which is installed on the shaft 2 and configured for detecting the position or the angular excursion of the shaft 2 , by clo sing the feedback loop of the control imparted by actuator 6 .

The installation of sensor PS is almost necessarily implemented on the shaft 2 and not on the actuator 6 or on the coupling 8 , so as to prevent the indication of the angular position ( absolute position or angular excursion) detected by sensor PS from being influenced by the tolerances of the power train upstream the shaft 2 . In this regard, the possible presence of a position sensor or of a position transducer on the actuator 6 is not suf ficient to detect the position of shaft 2 , because the tolerances of the power train upstream the latter always require positioning the sensor PS on the shaft itsel f ( or, generally speaking, on a mobile unit of the control assembly) .

The sensor PS is necessary particularly when the j urisdiction of homologation of the vehicle requires an on-board diagnosis system of the equipment which may af fect the polluting emissions of the vehicle ; in this regard, the swirl valves 4 are no exception . From what has been stated in the foregoing it is possible to infer the technical problem connected to the prior art : the actuation diagnosis may be implemented only and exclusively by means of the position sensor PS , which involves further costs and further complications in equipping the engine , being it necessary to provide lines for the electric supply and for the signals towards the sensor PS .

Obj ect of the Invention

The invention aims at solving the technical problem outlined in the foregoing . Speci fically, the invention aims at providing an actuation diagnosis of a control assembly, particularly for the swirl valves of an internal combustion engine , which does not require the presence of additional sensors such as the sensor PS described in the foregoing .

Summary of the Invention

The obj ect of the invention is achieved by means of a system and a method having the features provided in the claims that follow, which form an integral part of the technical disclosure provided herein in relation to the invention .

Brief Description of the Figures

The invention will now be described with reference to the annexed Figures , which are provided by way of non-limiting example only, and wherein :

- Figure 1 and Figure 2 , already described in the foregoing, are perspective views of a head of an internal combustion engine of a known type , equipped with a control assembly of swirl valves which is also known,

Figures 3 to 6 , already described in the foregoing, schematically show various examples of control assemblies of a known type ,

- Figures 7 , 8 and 9 show a system for actuation diagnosis according to the invention, and various operational aspects of the invention .

Detailed Description

Referring to Figure 7 , reference number 10 generally denotes a system for actuation diagnosis of the control assembly SW . According to the invention, the system 10 may be used not only for the actuation diagnosis of the control assembly SW ( the assembly SW being such as shown in each of the Figures 1 , 2 , 3 , 4 , 5 , 6 ) , but also for the actuation diagnosis of any control assembly comprising a mobile unit and an actuator operatively connected to the mobile unit , in order to control a movement thereof along an actuation coordinate .

According to the invention, the system 10 comprises a warning element 12 , configured for being connected to the mobile unit and for performing an integral movement with the mobile unit along the actuation coordinate , and at least one abutment element 14 , 16 ( in the present case , by way of example , a pair of abutment elements ) configured for limiting the movement of the warning element 12 along the actuation coordinate upon the occurrence of a contact with the warning element 12 itsel f .

The actuation coordinate may comprise , for example , a linear coordinate or a rotation coordinate , as is the case in the preferred embodiment shown in the Figures .

In the preferred embodiment of the diagnosis system 10 , which operates on the control assembly SW, the mobile unit comprises the shaft 2 , which is rotatable about the respective longitudinal axis X2 , and the actuation coordinate therefore comprises a rotation coordinate . The at least one abutment element comprises a first abutment element 14 and a second abutment element 16, which describe an extension of the movement of the warning element 12 (and consequently of the shaft 2 itself) controllable by means of the actuator 6, in this case of a rotary type.

Referring to the Figures 7 to 9, the warning element 12 is a radially projecting element with respect to the shaft 2 (e.g., an cam-like element) , and it is rotatable therewith about the longitudinal axis in positions between the abutment elements 14, 16. Preferably, the elements 14, 16 are configured and sized so that they cannot be overcome by the warning element 12, therefore representing not only a limitation, but a real boundary for the movement of the warning element 12 (and of the shaft 2) . However, other embodiments are possible wherein the abutment elements 14, 16 may be overcome upon achieving an excessive contact force between them and the warning element 12.

Moreover, although the elements 14, 16 are schematically shown as being distinct elements, they may be formed by two distinct parts or surfaces of one and the same component, or even by two opposite faces of one and the same element, which are both adapted to be contacted by said warning element in the movement imparted by actuator 6.

By means of the actuation diagnosis system 10 it is possible to implement a diagnosis method which does not require providing any position sensor on the mobile unit of the control assembly the actuation whereof is being diagnosed. Unlike the prior art, and very advantageously, the mobile unit itself acts as a "sensor" for the diagnosis, thanks to the warning element 12.

Generally speaking, the method according to the inventions comprises:

- controlling a movement of the mobile unit along the actuation coordinate , which is determined by the actuation imparted by the actuator which drives the mobile unit , wherein the movement of the mobile unit comprises an extension at least partially limited by the one or more abutment members , and

- detecting an anomaly condition in the movement of the mobile unit , wherein the anomaly condition comprises at least one of an anomaly condition in an interaction between the one or more abutment members and the warning element , and an anomaly condition in negotiating the extension itsel f .

The various possible conditions will now be described in detail , also referring to the preferred embodiment , wherein the system 10 is applied to the actuation diagnosis of the mobile unit 2 .

An anomaly condition in the interaction between said one or more abutment elements and said warning element may comprise , alternatively : i ) a failure to achieve a contact condition between the warning element and at least one abutment member, when a control is imparted to the mobile unit (by the actuator ) of suf ficient magnitude to achieve said contact condition, ii ) overcoming at least one abutment element by the warning element , in particular when the control imparted to the mobile unit is insuf ficient to said overcoming, iii ) achieving a contact condition between the warning element and at least one abutment element in a manner not corresponding to a control imparted to the mobile unit by the actuator .

An example of anomaly condition in negotiating the extension comprises iv) negotiating said extension in a time not corresponding to a control imparted to the mobile unit . Each of the conditions i ) , ii ) , iii ) , iv) corresponds to a situation wherein the control imparted by the actuator leads to a inconsistent response of the mobile unit , as detected by means of the warning element 12 .

In the case of condition i ) , the normal operating condition of the control assembly, or reference operating range, may correspond to a movement of the mobile unit confined within a fraction of the extension, and speci fically a fraction of the extension such as to exclude a contact between the warning element and the at least one abutment element . Therefore , detecting an anomaly condition comprises controlling a movement of the mobile unit beyond the fraction of the extension of a suf ficient magnitude to achieve a contact condition between the warning element and an abutment element , reporting an anomaly i f the abutment element ( s ) is/are not reached .

With reference to Figure 9, in the preferred embodiment of the invention, the logics of anomaly diagnosis as per condition i ) may correspond to defining a reference operating range for the shaft 2 ( and for the warning element 12 ) corresponding to an angle A12N . The angle A12N, in turn, corresponds to a fraction of the total extension between the abutment elements 14 , 16 and, speci fically, at opposite ends of the angle A12N two angles A12D are defined which correspond to angular excursions of the shaft 2 and of the warning element 12 which are used for diagnostic purposes .

In other words , i f the engine is working without any anomaly in the control assembly SW, the control of the swirl throttles 4 takes place within the angular excursion defined by the angle A12N, without ever contacting the elements 14 , 16 . In the long run, the shaft 2 may be subjected to wear or soiling phenomena, which limit the mobility thereof. If the normal condition corresponds to the movement within the angular excursion A12N, even abnormal actuations of a width shorter than controlled by the actuator 6 would appear as perfectly normal, if a diagnosis were not carried out outside the reference operating range. The logic for condition i) is the following: if the actuation imparted by actuator 6 is regular and devoid of anomalies within the reference operating range defined by the angle A12N, then the actuation must be regular also outside the operating range itself, and specifically must be such as to achieve the contact conditions between the warning element 12 and the abutment elements 14, 16. If the warning element 12 can reach the elements 14, 16 due to a control imparted by the shaft 2 of actuator 6 of a sufficient magnitude to reach the abutment elements 14, 16, then no anomaly is reported. If the elements 14, 16 are not reached, or if at least one of them is not reached, an actuation anomaly is reported.

In the case of condition ii) , the anomaly is reported for opposite reasons with respect to condition i) : in this case, always referring to Figure 9, the actuation diagnosis operated outside the angular excursion A12N leads to overcoming the abutment elements 14, 16, or to overcoming one of them, due to a control imparted by actuator 6 of a magnitude insufficient to generate the overcoming. This indicates a lack of consistency of the actuation during normal operation: an actuation of predefined magnitude leads to an excessive excursion of the shaft 2, with a consequent risk of breakage or jamming.

In the case of condition iii) , the anomaly is detected when the warning element 12 reaches, during normal operation or during the diagnosis implemented within excursion A12D, one or both elements 14 , 16 , due to an actuation imparted by actuator 6 which nominally corresponds to a position of the warning element 12 wherein no contact takes place with the elements 14 and/or 16 .

I f the abutment elements 14 , 16 ( one or both) are reached during the diagnosis , i . e . , in positions corresponding to the angular excursions A12D, an anomaly condition may moreover be reported when there is detected a variation in the contact force between the warning element 12 and one or both elements 14 , 16 after reaching the contact condition . In this case , the force variation is detected via the current absorbed by the actuator 6 , and it indicates that the actuation tends to continue beyond the element 14 and/or 16 , and therefore it is an abnormal actuation .

It is moreover possible to detect an anomaly by measuring the contact force between the warning element 12 and the abutment element 14 and/or 16 during the normal operation of the control assembly SW, i . e . , in a condition wherein nominally the warning element 12 is located within the angle A12N . In this case , detecting an incremental contact force indicates an abnormal actuation, because this is not consistent with the nominal conditions of the system .

The condition iv) corresponds to a control logic which aims at diagnosing actuation anomalies which cannot be detected only by means of the tests of reaching contact with the abutment elements 14 and/or 16 . Speci fically, during the diagnosis , elements 14 and/or 16 may be reached anyway, thus leading to a potential false negative . I f the information of reaching the contact is combined with a time information linked to the reaching, it is possible to diagnose abnormal operating functions corresponding to an operation slower than nominal , i . e . , slower than nominally envisaged on the bas is of the actuation imparted by means of actuator 6 .

In the case of the control assembly SW, the diagnosis method may conveniently be carried out when the engine is inoperative . A first possibility involves performing the diagnosis method during the key-of f intervals of the vehicle , whereas a second possibility involves performing the method during temporary stop intervals , e . g . , due to the intervention of the start and stop system . Obviously, the implementation of such a possibility requires a compromise between the requirements of the diagnosis and the requirements of a timely intervention of the start and stop system in case of a new start , which are an absolute priority .

In any case , the calibration of the diagnosis system 10 may be implemented at the first start of the system 10 . During such start , the system 10 performs a calibration cycle by achieving the contact with the elements 14 and 16 , therefore determining the width of the set of angles A12D+A12N+A12D and the relative position of each angular interval . The data are then stored in a memory of a control unit , and they are retrieved any time it is necessary to perform the diagnosis method according to the invention in the described fashion .

As already stated, the method according to the invention may be implemented on any control assembly, even those with linear actuation . An example may be a linear actuator wherein a warning element is rigidly connected to the mobile unit of the actuator itsel f , and it operates between a pair of abutment elements ( or even with only one abutment element ) which enable diagnosis logics corresponding to the conditions i ) , ii ) , ill ) , iv) . Also in this case it is possible to define a reference operating range corresponding to a fraction of the linear excursion between the abutment elements , the portions complementary to such excursions acting as diagnostic linear excursion, as it is the case for the angles / angular excursions A12D .

In any case , the advantage achieved by the invention and the solution of the technical problem mentioned at the beginning are perfectly clear : the possibility is given to diagnose actuation anomalies without the need of further position sensors . The mobile unit itsel f becomes the " sensor" of the diagnosis system according to the invention, thanks to the warning element 12 and to at least one abutment element 14 and/or 16 , and possible diagnosis conclusions may be inferred by means of the normal driving of the system actuator .

Of course , the implementation details and the embodiments may amply vary with respect to what has been described and illustrated, without departing from the scope of the present invention as defined by the annexed claims .

Claims

1. A method for actuation diagnosis of a control assembly (SW) , in particular a control assembly for swirl valves (4) , wherein the control assembly (SW) comprises a mobile unit (2, 4) , an actuator (6) operatively connected to said mobile unit (2, 4) to control a movement thereof along an actuation coordinate, and an actuation diagnosis system (10) comprising a detector element (12) connected to said mobile unit (2) and integral with said mobile unit (2) in a movement along the actuation coordinate, and one or more abutment elements (14, 16) configured for limiting the movement of the warning element (12) along the actuation coordinate upon the occurrence of a contact with said warning element (12) , the method comprising:

- controlling a movement of the mobile unit (2) along the actuation coordinate, wherein the movement of the mobile unit (2) comprises an extension at least partially limited by said one or more abutment elements (14, 16) ,

- detecting an anomaly condition in the movement of the mobile unit (2) , said anomaly condition comprising at least one of an anomaly condition in an interaction between said one or more abutment elements (14, 16) and the warning element (12) , and an anomaly condition in negotiating said extension.

2. The method according to claim 1, wherein said anomaly condition in the interaction between said one or more abutment elements (14, 16) and said warning element (12) comprises, alternatively:

- a failure to achieve a contact condition between said warning element (12) and said at least one abutment element (14, 16) when a control is imparted to the mobile unit of sufficient magnitude to achieve said contact condition,

- overcoming at least one abutment element (14, 16) , in particular when the control imparted to the mobile unit (2) is insufficient to said overcoming, reaching a contact condition between said warning element (12) and at least one abutment element in a manner not corresponding to a control imparted to the mobile unit (2) by the actuator (6) .

3. The method according to claim 1, wherein said anomaly condition in negotiating said extension comprises negotiating said extension in a time not corresponding to a control imparted to the mobile unit by the actuator (6) .

4. The method according to any one of claims 1 to

3, wherein said detecting an anomaly condition in the movement of said mobile unit (2) comprises defining a fraction (A12N) of said extension corresponding to a reference operating range of said control unit (SW) , the fraction of the extension being such as to exclude a contact between said warning element (12) and said at least one abutment element (14, 16) , wherein said detecting an anomaly condition comprises controlling a movement of the mobile unit (2) beyond (A12D) the fraction of said extension with a sufficient range to achieve a contact condition between said warning element (12) and said one or more abutment elements (14, 16) , and reporting an anomaly if the contact condition is not achieved for at least one of said abutment elements (14, 16) .

5. The method according to claim 4, wherein said detecting an anomaly condition comprises detecting a change in a contact force between said warning element and said at least one abutment element after the contact condition is reached.

6. The method according to any one of the preceding claims, wherein:

- the actuation diagnosis system (10) comprises a first abutment element (14) and a second abutment element (16) ,

- the mobile unit comprises a shaft (2) rotatable about a respective longitudinal axis (X2) , said actuation coordinate comprising a rotation coordinate,

- the actuator (6) is of the rotary type,

- the warning element (12) is an element radially projecting from said shaft (2) and rotatable with it about said longitudinal axis (X12) .

7. A system for the actuation diagnosis of a control assembly (SW) comprising a mobile unit (2, 4) and an actuator (6) operatively connected to said mobile unit (2, 4) to control a movement thereof along an actuation coordinate, the system comprising:

- a warning element (12) configured for connection to said mobile unit (2) and for integral movement with said mobile unit (2) along said actuation coordinate, and one or more abutment elements (14, 16) configured for limiting the movement of the warning element (12) along the actuation coordinate upon contact with said warning element (12) .

8. The system (10) according to claim 7, wherein:

- said at least one abutment element comprises a first abutment element (14) and a second abutment element (16) , the mobile unit (2) comprises a shaft (2) rotatable about a respective longitudinal axis (X2) , said actuation coordinate comprising a rotation coordinate,

- the actuator (6) is of the rotary type, the warning element (12) is a radially projecting element with respect to said shaft (2) and rotatable with it about said longitudinal axis (X2) in positions between said first abutment element (14) and said second abutment element (16) .

9. The system (10) according to claim 8, further comprising an intake manifold (IM) for an internal combustion engine, said intake manifold (IM) comprising rotation bearings for said shaft (2) , said shaft (2) carrying a plurality of swirl valves (4) in longitudinally spaced positions thereon.

10. A head (1) for an internal combustion engine comprising :

- one or more flame decks at cylinder positions of a crankcase of an internal combustion engine pairs of inlet conduits (IC) leading to a respective flame deck of said one or more flame decks, wherein : one of the inlet conduits of each pair is associated with a control assembly (SW) comprising a shaft (2) rotatable about a longitudinal axis (X2) and a swirl valve (4) fitted onto said shaft (2) and integrally rotatable with said shaft (2) about said longitudinal axis (X2) , the swirl valve being arranged at a wall of said head (1) whereat ends of inlet conduits (IC) opposite to the ends which terminate on the flame deck are located,

- the control assembly (SW) comprises an actuator (6) operatively connected to said shaft (2) to control a movement thereof along an actuation coordinate, and a warning element (12) connected to said shaft (2) and integral with it in a movement along the actuation coordinate, and a first and a second abutment elements (14, 16) configured for limiting the movement of the warning element (12) along the actuation coordinate upon the occurrence of a contact with said warning element ( 12 ) , the warning element (12) is a radially projecting element with respect to said shaft (2) and rotatable with it about said longitudinal axis (X2) in positions between said first abutment element (14) and said second abutment element (16) .