FR2628146A1 - IMPROVED ENDOTHERMIC ENGINE COMPRISING ADMISSION WITH ADJUSTABLE VORTEX INDEX - Google Patents

Abstract

In this engine, there is provided an additional duct 13 in which slides a flexible blade 14 capable of being placed projecting in a connection zone 15 formed between the intake duct 10 and a corresponding supply volute 11, in order to gradually throttle the passage section of said intake duct 10.

Description

(i) FRENCH REPUBLIC Publication No. 2,628,146 (to be used only

  for the NATIONAL INSTITUTE - Reproduction orders) OF INDUSTRIAL PROPERTY N of national registration 89 02682 e N denegstemntnaioal go 02682 PARIS

(Int Cl4: F 02 B 31/00.

@ APPLICATION FOR PATENT OF INVENTION A1

  Filing date: 1 March 1989. '() Applicant (s): Company known as: FIAT AUTO S.p.A.- IT.

  () IT priority, 11 March 1988, No. 67156 A / 88.

  Inventor (s) Bruno Andreatta: Alfio Puglisi.

  f Date of the public availability of the

  application: BOPI "Patents" No. 36 of 8 September 1989.

  0 References to other national documents appearing

: Holder (s)

  (Agent (s) Cabinet Beau de Loménie.

  (Advanced endothermic engine with adjustable vortex admission.

  ) In this motor, an additional conduit 13 is provided

  as which slides a flexible blade 14 able to be placed in - to ---

  protruding into a connection zone 15 formed between the inlet duct 10 and a corresponding supply volute 11 for progressively throttling the passage section.

wise of said intake duct 10.

NOT

IL_ to 9. 9 ,: I

  IL 1E \ / t.4 4 .., 1 ;. 1.,,,,,,,,,, I. The present invention relates to an endothermic engine of improved type, with high turbulence,

  especially of the fast diesel type with direct injection

  te, whose intake ducts are provided with means capable of adjusting the vortex index (or the vortex nature) of the engine supply air flow by

according to the regime of the latter.

  It is known that in combustion engines

  in particular in small diesel engines.

  the direct injection engine, it is particularly

  important to obtain a homogeneous mixture between air and fuel, to achieve the admission of air with a correct vortex index; to achieve this goal, we know many expedients such as by

  example, that of adopting

  Volute shaped. These well-known methods of

  those skilled in the art make it possible to give the index of

  tex the value that optimizes the combustion conditions

  for each of the different rotation regimes of the

  tor. In essence, with the devices mentioned above

  above, ideal vortex indices are obtained only in a restricted area of use of the engine while, when the engine speed conditions are outside this range, the vortex index is no longer suitable for

  characteristics required by the engine. The adoption of

  such as the projection of a compressed secondary air jet tangent to the intake volute for the purpose of varying the range of motion and, therefore, the vortex index of the intake air, or that of

  to be mounted in the intake duct of the inflatable elements

  capable of varying the geometry of this duct according to the operating conditions of the engine does not entirely solve the problem of ensuring that, for each regime, the intake air will have the correct vortex index, in that the processes using

  additional air have cooling intervals.

  relatively small and that, in any case, they require a source of compressed air

  that, on the other hand, it is difficult to control exactly

  the geometry of the intake duct using inflatable elements. The object of the invention is to provide an endothermic engine equipped with intake devices capable of generating the strong vortex of the intake air flow of the

  motor and give the vortex index the optimum value

  male for the different conditions of diet and

engine age.

  This purpose is achieved by the invention by the fact

  that this invention relates to an endothermic motor

  that, in particular of the fast diesel type with

  of the kind comprising at least one combustion chamber

  at least one intake duct and at least one

  corresponding power supply, which connects

  intake to an inlet of said chamber

  combustion chamber, characterized in that it comprises, for each volute, a flexible blade which slides in an additional duct opening into the volute, to the right of the connection zone between the volute and the intake duct , and means capable of selectively positioning said partially projecting blade within said connection zone,

  in different positions' of operation in the-

  which said blade is adapted to reduce a section of

  passage of said intake duct to a variable degree.

  Other features and advantages of the

  will be better understood when reading the description of

  following statement of an example of

  reference to the attached drawing, which is a schematic plan view

  simplified and partly sectional version of an endothermic motor produced in accordance with the

the invention.

  In the drawing, there is designated as a whole by 1 an endothermic motor of any known type, which is in the case considered a fast diesel engine with direct injection, which has been shown only for

  simplify, part of block 2 and part of the

  weary 3 which overcomes the block and which is seen in section. Block 2 comprises at least one cylinder 4 which delimits in its interior volume a combustion chamber 5 closed at the top by the cylinder head 3 and provided with intake and exhaust ports 8 which are intended to be closed by

  respective known valves, which have been omitted from

  present to simplify the drawing and which may

  smooth, for example, through valve seats

  9 in the cylinder head 3 at the level of the

  7 and 8 (for simplicity, only

  the seat 9 provided at the orifice 7). The model

  may include one or more chambers of com-

  bustion 5 of the aforementioned type and the cylinder head 3 is provided,

  for each chamber 5, an exhaust duct

  tif, of a known type and which has been omitted from

  simplify, and an intake duct 10 which terminates

  tangentially in a feed volute 11,

  of known type, provided in the cylinder head 3 in a posi-

  which overcomes the orifice 7 so as to connect the hydrau-

  5, in particular, to lead tangentially into the volute 11, the conduit 10 is curved and has a radius of curvature inverse that of the volute 11, so that a flow of air sucked 12 to enter the inlet port 7 after having traveled a substantially S-shaped trajectory. According to the invention, it is furthermore provided that

  the interior of the cylinder head 3, for each chamber of

  5, at least one additional conduit 13 disposed substantially parallel to the conduit 10 and curved of

  the same way as this one to lead tangentially

  inside the volute 11, in particular in

  an area 15 connecting the volute and the con-

  10. The additional conduit 13 describes a curve with a large radius of curvature and is formed by the part

  of the extrados flank 16 of the duct 10 so as to open

  expensive substantially parallel to the flank of intrados 18 of the volute 11 which corresponds to it. According to the invention,

  it is provided in the additional conduit 13, a

  elastically flexible hose 14, which is made

  preferably made of spring steel and / or

  any self-lubricating synthetic plastic

  to resist the temperatures encountered in use

  in the duct 10 and in the volute 11; the la-

  me 14 is longer than the length

  duct 13, so as to come out of this projecting duct,

  at both ends of the latter, by its opposite ends

  19 and 20. The end 19 leaves the conduit 13 sensi-

  the right of the orifice of the conduit 10 and is connected to motor means capable of varying the axial position of the blade 14 in the conduit 13; these means are constituted, for example, by an actuator 21 of any known type controlled by a central unit 22 as a function of the rotational speed and the load of the engine 1, parameters which are picked up by one or more sensors 23, also of known type and that we will omit

  therefore to describe in the following to simplify the descrip-

  tion. The opposite end 20 of the blade 14 opens at

  contrary in the aforementioned zone 15, appreciably

  puyant against the intrados 18 of the volute 11 and in challenge,

  significantly extending the profile of the former

  trados 16 of the conduit 10. According to the axial position of the

  blade 14, which is controlled by the plant 22 by the machine

  actuator 21, this end 20 can take

  selectively within the connection zone.

  a plurality of operating positions in which the blade 13 reduces to a variable degree the passage section which remains available for the flow.

2628146

  12 in the intake duct 10. In essence, moving along the duct 13 in the direction of the arrows under the control of the actuator 21, the blade 14

  is able to modify at will the section of the con-

  duit 10 while ensuring in each case an optimal connection with the volute 11 and realizing the section variation precisely in the connection zone 15,

  which is precisely the area that is particularly critical

  only for the formation of the fields of motion which

  minimize the degree of turbulence that the airflow 12 can

  reach at the entrance of orifice 7.

  The operation of the engine 1 carried out according to the invention is as follows. During the admission phase

  (or when the orifice 7 is open), the air flow of

  12 is sucked mainly through the con-

  10, the possible fraction of the air flow that infiltrates

  13 is absolutely insignificant, the air sucked by the duct 10 enters the volute 11 and, because of the geometry of this duct and this volute, it is rotated according to the profile of the volute 11 of to create a vortex before the air charge is introduced into the chamber of

  combustion 10 through the orifice 7, and to promote

  if the spraying of the fuel charge that is

  It is evident that the vortex index that the air flow 12 acquires after having been admitted into the volute 11 depends on the width and the orientation of the most important part of the chamber. small passage section whose air flow 12 has for its flow. It is therefore obvious that the presence

  of a greater or lesser part of the blade 14

  connected in the connection zone to the connection 15, the bar of the size of which depends on the axial position

  of this blade in the duct 13, has the effect that the

  air inlet velocity in the volute 11 is all

  higher on average, and steered even more tangentially

  tually, that the end 20 of the blade 14 makes more

  stage protruding on the conduit 13; this causes an increase

  the amount of movement of the air in the

  11 and therefore promotes the maintenance of a

  vortex dice greater than that which one would have with the

  blade 14 in the retracted position or with the end 20

  retracted inside the duct 13. The center

  trale 22 is. so able to pilot the maneuver of

  the actuator 21 according to the operating parameters

  motor (for example, the speed of rotation of the crankshaft), which are sensed by the sensor or the sensors 23, so as to each time to take the blade 14 an axial position capable of determining a more or less extension large of this protruding blade or cantilever outside the conduit 13, the side of the end 20, so as to vary at will, in a controlled manner, the geometry and the section of the conduit in the zone of connection 15, adapting them to

  values that are optimal for the functioning regime.

  motor that is picked up by the sensors 23.

  In essence, the presence of conduit 13 and

  the corresponding sliding blade 14 which have been de-

  written above allows to give to the admission duct

  in a simple and economical way, as well as very ef-

  ficace, a section with variable geometry that allows op-

  for each speed of operation of the engine 1, to calculate the vortex index which is taken by the intake air flow 12, maintaining in any case a vortex index

  better than that which can be obtained in

  known types but lacking conduit 13 and

  blade 14, both at low speeds and at higher speeds

  1. In fact, it is obvious that

  that regardless of the axial position of the blade 14 inside the conduit 10, we always get a constriction of the passage section of this conduit and, therefore, an increase in the speed of the air

  at the entrance of volute 11 and a consecutive increase

  ve of the vortex index. In addition, according to another

  feature of the invention, the displacement of the blade 14 makes it possible to vary only the geometry of the appropriate zone and also to vary the vibration index.

  tex of the airflow at the inlet 12 in a very reproducible way

  ductile, while leaving unchanged the geometry of

appears from the intake duct 10.

  Of course, various modifications will be possible

  be made to the device which has just been described

  as a non-restrictive example without departing

framework of the invention.

R EV IN DI C AT ION

  1 - endothermic engine, in particular, of the type

  diesel direct injection, of the type which

  takes at least one combustion chamber, at least one

  intake duct and at least one volute of food

  corresponding connection, which connects the intake duct to an inlet of said combustion chamber, characterized in that it comprises, for each volute

  (11), a flexible blade (14) which slides in a

  additional duit (13) opening into the interior of the-

  said volute to the right of the connection zone between this volute and the intake duct (10), and means (21, 23) capable of selectively positioning said blade (14) partially projecting therein

  of said connection area (15) in different po-

  operating conditions in which said blade

  (14) is adapted to reduce the passage section of said con-

  intake duct (10) to a varying degree.

  2 - Motor according to claim 1, characterized

  in that said additional duct (13) in the-

  which slide said flexible blade (14) opens into the-

  said connection zone (15) by taking an orienta-

  tangential to said feed volute (11).

  3 - Motor according to claim 1 or claim

  2, characterized in that said means (21) for selectively positioning said flexible blade

  (14) within said additional conduit (13)

  take an actuator (21) connected to a first end

  tee (19) of said flexible blade (14) which is opposite a second end (20) of said same blade which is

  able to extend projecting out of said sup-

  part (13), within said connection zone

  (15), and at least one sensor (23) for capturing

  the parameters of the operation of said engine (1) and

  which is able to control said actuator (21).

  4 - Motor according to any one of the claims

  previous arrangements, characterized in that said flexible blade

  xible (14) is made of spring steel.

  - Motor according to any one of the preceding claims, characterized in that the additional duct (13) is made in an extrados sidewall (16) of the duct intake duct (10), the latter and the

  conduit (13) being both curved.

PL Single

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