FR2795152A1 - SWITCHING INSTALLATION FOR THE AIR AND EXHAUST GAS SUPPLY OF AN ENGINE - Google Patents

Abstract

Installation for switching (1) the air supply between the stratified supply mode and the homogeneous supply mode. It comprises a first supply channel (3) which closes with a first drawer (40) and a second supply channel (4) which closes with a second drawer (41) in the body (2). The first and second drawers (40, 41) are made on a common rotating shaft (10). This shaft has a first flat (11a) at the level of the first drawer (40) and a second flat (12a) at the level of the second drawer (41). The second flat (12a) is in a precise angular position relative to the first flat (11a).

Description

The present invention relates to a switching installation for

  switch the air and / or exhaust gas supply to an internal combustion engine between the

  stratified feeding mode and homo- feeding mode

  uncomfortable. State of the art: According to the article "Benzin-Direkteinspritzungeine neue Herausforderung fur zuk nftige Motorsteuerungssysteme" in MTZ Motortechnische Zeitschrift 58 (1997) 9, p. 458 and following, it is known that internal combustion engines

  direct fuel injection, in particular direct injection

  gasoline, advantageously use a motor control according to which, in the range of the low loads of the engine, one works in mode of stratified feeding and in the range of the high loads, one works in mode

homogeneous feeding.

  In stratified feed mode, the motor

  internal combustion works with a filling of cylinders

  dres highly laminated and a large excess of air so that

  fuel consumption is as low as possible.

  The subsequent injection of fuel, just before the time of ignition corresponds to the search for the ideal state of a distribution of the combustion chamber in two zones: a cloud formed of an air / fuel mixture, susceptible burn at the spark plug, and an insulating layer

  formed of air and residual gases. This makes it possible to operate

  operating the internal combustion engine, practically without

  throttling avoiding alternating load losses.

  When the load applied to the engine increases and the same applies to the quantity of fuel injected, the layer supply cloud becomes richer and there is a deterioration in the quality of the gases.

  exhaust. In the range of higher loads, the mo-

  For this reason, the internal combustion engine works in homogeneous feeding mode with homogeneous filling of the cylinders. The injection is already done during the aspiration phase to achieve a good mixture between the fuel

and the air.

  By switching between the strategic feed mode

  homogeneous feeding mode or vice versa, it must be taken into account that in stratified feeding mode, in

  To some extent, it is advantageous to have a reinjection

  tion of exhaust gases consisting in adding to the air supply a predefined quantity of exhaust gases which are reinjected; on the contrary in homogeneous supply mode, no exhaust gas re-injection is required or in all

  very few cases. For air supply to the combustion engine

  internal bustion, therefore requires switching facility to switch between power mode

  laminate and homogeneous feeding mode.

Advantages of the invention:

  The present invention relates to a switching installation

  tion of the type defined above, characterized by: * a first supply channel passing through a body and the section of which is controlled by means of a first drawer, * a second supply channel passing through the body and the section is controlled using a second drawer, * the first drawer and the second drawer being made on a common rotating shaft, * the rotating shaft having at the level of the first drawer at least a first flat and at the level of the second drawer, at least a second flat and * the second flat being made on the rotating shaft with

  an angle defined with respect to the first flat.

  The switching installation according to the invention

  offers the advantage that the realization of the drawer with met-

  dishes for the first and second supply channel, on

  a common rotating shaft is a special solution-

  robust, wear-free and easy to assemble. The rotating tree

  can be slid into the housing body as a part

  fully pre-assembled. This removes any subsequent fixation

  of drawers produced separately in the form by

  example of flaps on the rotating shaft, mounted. This corresponds to

  is a particularly simple and inexpensive assembly. Flats can be made in the rotating shaft as soon as it is

  manufacturing, with an angular offset defined exactly between-

  be the flats, for example an offset to the square. In

  an embodiment of the drawer in the form of a shutter manufactured se-

  on the other hand, that it is necessary to mount on the rotating shaft for example by welding, tightening or matting, one can have such a faithful and exact angular alignment only by implementing

significant resources.

  The means set out in the sub-claims

  correspond to developments and improvements

  advantageous of the switching installation object of the re-

main vendication.

  It is possible to make each time two flats on either side of a flat central spacer, to leave the section in the open state as large as possible. Between the flats, an area can be made that is closely adjacent to the

  receiving hole and which closes tightly, simple-

  the first and second supply channels.

  It is advantageous to hold the rotating shaft in a basic position defined using a return spring, for example mounted on a socket. In the event of a failure of the shaft drive, the switching system then comes to a determined switching position, by

  example the switching position for the power supply mode

  homogeneous tation, so that the internal combustion engine

  can at least continue to operate with reduced power

  pick. To activate the rotating shaft, the bush can

  wear an eccentric pin on which a linkage acts.

  It is advantageous that the rotating shaft is closed in a leaktight manner by a seal as well at its end.

  close to the socket only at its opposite end.

  It is also advantageous to block the rotating shaft in the receiving hole, leaving an axial clearance to compensate for manufacturing tolerances and to rotate the shaft in the body of the housing with only low friction. To ensure that the rotating shaft is in a defined axial position, despite the axial play, the return spring can perform the additional function of an axial pressure spring and for this, for example, the return spring in the form of spiral spring pushes the tree

  rotating, axially against a stop.

  The switching installation has advantageously

  for each cylinder of an internal combustion engine, each three supply channels with a first channel

  supply and a third supply channel provided-

  pure combustion air and a second supply channel to provide a mixture of reintroduced combustion gases and pure combustion air. The first feed channel and the

  second feed channel can be closed alternative-

  by the drawer in the shape of a rotating axis. It is advantageous to integrate a connection channel into the switching installation for connecting the second supply channel through which the reintroduced exhaust gases pass with one

  other supply channels to add combustion air

  pure rant to reintroduced exhaust gases. The realization of this link channel directly in the installation of

  switching allows a compact construction.

Drawings:

  A particularly advantageous embodiment

  tagger of the invention is shown in a simplified manner in the accompanying drawings and will be described below so

more detailed.

  Thus: * FIG. 1 is a bottom view of a detail of the switching installation according to the invention,

  * Figure 2 is a front view of the installation of

  mutation according to the invention, * Figure 3 is a sectional view along line III-III of Figure 2,

  * Figure 4 is a side view of the installation of

  mutation according to the invention, * Figure 5 is a sectional view along the line V-V of Figure 4, * Figure 6 is a perspective view of a rotating shaft

  of the switching installation according to the invention.

  Description of the exemplary embodiment:

  Figure 1 shows a view from below of the installation.

  switching lation according to the invention; Figure 2 in mon-

  be a side view. The switchgear door installation

  balement reference 1 and is used in the embodiment to switch an air and exhaust gas supply to an internal combustion engine between a stratified supply mode and a homogeneous supply mode. The drawings only show a detail of the switching installation 1 at the level of a cylinder of an internal combustion engine which

  general has several cylinders for example four cy-

  lindres. Figures 1 and 2 continue to the left and to

  right every time in the same way by identi-

  ques corresponding to neighboring cylinders.

  The switching installation 1 according to the invention is used in the embodiment to be supplied in stratified supply mode corresponding to the low range

  charges of an internal combustion engine, with associated cylinders

  of this engine, combustion air to which are reintroduced exhaust gases. In power mode

  homogeneous, for high loads of the internal combustion engine

  dull, the switching installation 1 according to the invention is switched so that the combustion air does not receive gas

  exhaust or only very reduced.

  The switching installation 1 is in the form of an intermediate flange and can be mounted with the front face 6 shown in FIG. 2, using screws placed in the fixing holes 7, 8, directly on

  the cylinder head of the internal combustion engine.

  At the opposite side of the switching installation 1, there is in known manner a suction module

  or a suction tube for suction, distribution and wire-

  trate the combustion air and supply the exhaust gases to be rein-

to produce.

  The body 2 has a first feed channel

  mentation 3, a second feed channel 4 and a third

  feed channel 5. Through the first feed channel

  tation 3 and the third supply channel 5, each time pure combustion air is supplied to the associated cylinder. On the contrary, by the second supply channel 4, the corresponding cylinder of the internal combustion engine is supplied with a mixture formed of reintroduced exhaust gases and of pure combustion air. In the switching installation 1 fixed by flanges to the cylinder head, the exhaust gases reintroduced into the second supply channel 4 pass through the connection channel 9. To add pure combustion air to these exhaust gases thus reintroduced, a connecting channel 9 comes from the third supply channel 5; this channel 9 passes through the body 2 of the housing towards the second supply channel 4 of the neighboring cylinder on the right according to FIG. 2.

  In Figure 2 appears how the connecting channel

  sound 9 connected to the third supply channel 5 of the cylinder

  left neighbor, is led to the second supply channel 4.

  To explain this, Figure 3 shows a section along the line III-III of Figure 2; this section shows that the connecting channel 9 opens into the second channel

  4. In this way, the second feed channel

  tation 4 receives from the third supply channel 5 of the cylinder

  dre next to the left, according to the drawing, pure combustion air which mixes with the reintroduced exhaust gases to form an exhaust gas-air mixture. By integrating the connecting channel 9 into the body 2 of the switching installation 1,

  a particularly compact construction is produced.

  The housing body 2 comprises a drilling for

  ception 33 extending transversely to the first channel

  supply 3 and the second supply channel 4. This

  çage receives a rotating shaft 10 which best appears in Figure 6. In the area of the first feed channel 3, the rotating shaft 10 has a first flat 11a and a third flat 11b; in the area of the second feed channel 4, the rotating shaft has a second flat 12a and a fourth flat 12b. The flats lla, 11b are

  made in the rotating shaft 10, furthermore of cy-

  lindrique, on both sides of a central spacer 13, flat; these flats are for example made with strawberries. Correspondingly, the flats 12a, 12b are made of

  on either side of a flat central spacer 14. The

  dishes 11, 12 according to the embodiment are offset from each other by 90. At the first flat 11a and the third flat 11b, there is a first drawer 40 allowing the first supply channel 3 to be opened or closed.

  on the contrary, at the level of the second flat 12a and the fourth

  flat 12b, there is a second drawer 41 allowing the second supply channel to be opened or closed 4. Between the flats lla, llb on the one hand and 12a, 12b on the other hand, there is a cylindrical zone 39 which separates the first channel tightly

  supply 3 and the second supply channel 4.

  Depending on whether the rotating shaft 10 occupies the first

  first position represented in FIGS. 2 and 3 or a second position turned practically 90 relative to it,

  either the first supply channel 3 is open and the

  cond feed channel 4 is closed, or conversely the first feed channel 3 is closed and the second channel

power supply 4 is open.

  The first position of rotation shown in Figures 2 and 3 corresponds to the homogeneous supply mode of the internal combustion engine. To pass from the homogeneous feeding mode to the stratified feeding mode of the internal combustion engine, the shaft 10 is rotated by 90 in its second position of rotation. For the first position of rotation of the rotating shaft 10 shown in FIG. 2 and corresponding to the homogeneous feeding mode, the first feeding channel 3 is open and that is why only the middle spacer 13 appears. The second supply channel 4 is on the contrary closed and the flat 12 is turned towards the side of the observer. Correspondingly, in homogeneous supply mode, no exhaust gas-air mixture can pass through the second supply channel 4 to arrive in the corresponding cylinder.

of the internal combustion engine.

  In stratified supply mode of the

  internal bustion, the first supply channel 3 is closed,

  so that the pure combustion air which supplies the cor-

  respondent of the engine no longer passes through the first supply channel 3 but only through the third supply channel 5. In addition, an exhaust gas-air mixture arrives through the second supply channel 4 in the corresponding cylinder of internal combustion engine. The housing body 2 has at its end

  upper according to FIG. 2, a first cylinder extension

  drique 15 and at its lower end a second extension

  cylindrical ment 16. In the assembled state, below the first cylindrical extension 16 of the housing body 2, a

  socket 17 fixed to the rotating shaft 10 protrudes from the body 2.

  This socket 17 consists of a cylindrical segment 18 and

  a collar 19. The cylindrical segment 18 between the collar

  lerette 19 and the lower extension 16 of the body 2 door

  a return spring 20 formed in the exemplary embodiment

  tion by a spiral spring. A first end 22 of the return spring 20 is applied against a stop 21 of the

  body 2. The second end 23, opposite the return spring

  pel 20 is held in a groove 24 in the flange area 19 of the bush 17 as shown in FIG. 6. By turning the shaft 10 and the bush 17 integral in rotation with the rotating shaft 10, the spring is prestressed 20, so that the rotating shaft 10 returns to the basic position shown in FIGS. 2 and 3 corresponding to the first of the two rotation positions, offset by 90,

  when the actuating force is released.

  To actuate the rotating shaft 10, a pin 25 is provided eccentrically on the socket 17 integral

  in rotation of the rotating shaft 10. It is possible to connect a trin-

  glazing not shown in the drawing on the spindle 25 to turn all the rotating shafts 10 of all the cylinders of the

  internal combustion engine, synchronized by simple coupling

  smoothing of the linkage. The actuation of the linkage can be done for example pneumatically using a vacuum capsule. Alternatively, one can also

  activate the linkage for example by electromechanical means

  or an electric motor. The parts affected by

  the socket 17 appears clearly in FIG. 1.

  The flats 11a, 11b, 12a, 12b provided on the rotating shaft 10 appear very particularly in the view in

  perspective of the rotating shaft 10 shown in FIG. 6.

  This figure also shows the position of the socket 17 and the return spring 20. Figure 6 also clearly shows that the rotating shaft 10 has a first seal

  sealing 26 provided between the second flat 12a and the qua-

  third flat 12b and on the socket 17 and used to make

  the sealing of the second supply channel 4 to the outside

  laughing. This first seal 26 can for example be made of Teflon or a perfluorinated elastomer. The opposite end of the rotating shaft 10 is provided with a second seal 27 to seal the first channel

  supply 3 having at the same time the function of a bearing.

  For this seal 27, a duroplastic synthetic material, in particular Ryton (brand), is advantageously used. The sealing is further completed by a flap of

closure 28.

  FIG. 4 is a side view of an installation

  switching operation 1 according to the invention. This figure shows, among other things, the body 2, the connecting channel 9, the

  bush 17 and return spring 20.

  Figure 5 shows a section along the line V-V of Figure 4, that is to say an axial section in the rotating shaft 10. This view shows more clearly the construction

  of the rotating shaft 10 and of the parts connected thereto.

  A groove 29 receives the second seal 27 blocked in the groove 29 by a closure plate 30. The closure plate 30 of this exemplary embodiment is held by means of a first screw 31 screwed in a first thread 32 of the rotating shaft 10. The shutter

  shutter 28 provides coverage and completes the watertight

  cheeness; this flap closes the receiving hole 33 passing through

  body 2 transversely to feed channels

  3, 4, 5 and receiving the rotating shaft 10.

  The first seal 26 is placed between a shoulder 34 of the rotating shaft 10 and a shoulder 35 of the body 2. The sleeve 17 is fixed using a second screw 36 and with the interposition of a washer 37 integrally rotated against the rotating shaft 10. The second screw 36 is screwed to this

  effect in the second thread 38 of the rotating shaft 10.

  The assembly is advantageously carried out as follows: First of all, the second seal 27 is preassembled using the closure plate 30 and the screw 31 on the rotating shaft 10 and the first seal is slid. seal 26 on the shaft 10. The rotating shaft 10 is

  then introduced from above according to FIG. 5 in the per-

  receiving hole 33. The return spring 20 is placed on the bush 17 and the latter is fixed on the rotating shaft 10 to

using the second screw 36.

  It is advantageous that after having connected the bushing 17 to the rotating shaft 10, there remains an axial clearance formed by the gap 42. This guarantees the ease of movement of

  rotation of the rotating shaft 10, without risking damage

  rer by excessive friction. To ensure at the same time that the rotating shaft 10 is in a defined axial position, the return spring 20 has the additional function

  a compression spring. The return spring 20 is

  d between the body 2 and the collar segment 19 of the sleeve 17. The return spring 20 applied against the sleeve 17 pushes the rotating shaft 10 axially against

  the shoulder 35 of the housing body 2 acting as a stop.

  The rotating shaft 10 makes it possible to switch very quickly

  the air supply between the stratified supply mode and the homogeneous supply mode. Like the tree

  turning 10 does not require separate parts for the ti-

  laugh, for example shutters, but that the drawers 40, 41 are made in a simple manner like flats l1a, llb or

  12a, 12b on the rotating shaft 10, there is an ease of mounting

  tage and a realization with a particularly weak wear-

  corn. For maintenance, the rotating shaft 10 can be dismantled without difficulty. The angular reserve between the flats 11a, 11b on the one hand and the flats 12a, 12b on the other hand is predefined exactly when the rotating shaft is manufactured. 10. Therefore, there is no more adjustment to be made at the Il

  mounting. The solution according to the invention is characterized by or-

  be of very high resistance and low wear. In particular, the rotating shaft 10 does not risk seizing up

  in the receiving hole 33. In addition, when switching

  tion between the homogeneous feeding mode and the stratified feeding mode, the developed noise is extremely low.

Claims (10)

R E V E N D I C A T I ON S   1) Switching installation characterized by: * a first supply channel (3) passing through a body (2) and the section of which is controlled by means of a first drawer (40), * a second supply channel (4) passing through the body (2) and the section of which is controlled by means of a second drawer (41),   * the first drawer (40) and the second drawer (41) being reacted   read on a common rotating shaft (10), * the rotating shaft (10) having at the level of the first drawer   (40), at least a first flat (11a) and at the level of the   cond drawer (41), at least a second flat (12a), and * the second flat (12a) being formed on the rotating shaft (10) with an angle defined relative to the first flat (11a). 2) Installation according to claim 1 characterized in that the rotating shaft (10) is housed in a bore (33) of the body (2) and a zone (39) is formed between the first flat (11a) and the second flat (12a) on the rotating shaft (10), area tightly applied against the wall of the bore (33) to seal between the first channel   feed (3) and the second feed channel (4).   3) Installation according to any one of claims 1 or 2, characterized in that   the second flat (12a) is offset by an angle of 90 relative to port on the first flat (lia).   4) Installation according to any one of claims 1   to 3, characterized in that the rotating shaft (10) has a third flat (11b) at the level of the first drawer (40) and the first flat (11a) and the third flat (llb) are made on both sides of a flat middle spacer (13).    ) Installation according to any one of claims 1 to 4, characterized in that   at the second drawer (41), the rotating shaft (10) comprises   carries a fourth flat (12b) and the second flat (12a) and the fourth flat (12b) are made on both sides   a flat central spacer (14).   6) Installation according to any one of claims 1   5, characterized in that the rotating shaft (10) is held in a basic position by a return spring (20).   7) Installation according to claim 6, characterized in that the return spring (20) is a spiral spring mounted on a sleeve (17) integral in rotation with one end of   the rotating shaft (10), one end (23) of the return spring   pel (20) being attached to the sleeve (17) and another end   (22) of the return spring (20) being fixed to the body (2).   8) Installation according to claim 7, characterized in that the sleeve (17) is removably connected to the shaft   turning (10) by a screw connection (36).   9) Installation according to claim 7 or 8, characterized by a pin (25) mounted eccentrically on the sleeve (17), to receive an actuating linkage of the rotating shaft (10)    ) Installation according to any one of claims 7   9, characterized in that the rotating shaft (10) has a seal (26, 27) both at its end near the bush (17) and at its opposite end.   11) Installation according to any one of claims 7 at 10,   characterized in that the rotating shaft (10) is locked axially   Lely with axial play through the sleeve (17) and the spring   reminder (20) acting on the bush (17) pushes the shaft around   nant (10) against an axial stop (35).   12) Installation according to any one of claims 1   to 11, characterized in that it is applied to switching an air and / or exhaust gas supply of an internal combustion engine between a stratified supply mode and a homogeneous supply mode. 13) Installation according to claim 12, characterized in that for a first position of rotation of the rotating shaft   (10) corresponding to the stratified feeding mode, the first   first supply channel (3) is closed and the second supply channel (4) is open, and in a second position of rotation of the rotating shaft (10) corresponding to the homogeneous supply mode, the second supply channel '' food (4)   is closed and the first supply channel (3) is open.   14) Installation according to one of claims 12 or 13,   characterized in that the internal combustion engine has several cylinders and for each cylinder of the internal combustion engine, the body (2) each has a first channel   feed (3) and a second feed channel (4) as well   if each time a rotating shaft (10) with a first ti-   black (40) and a second drawer (41), and for each cylinder of the internal combustion engine, the body (2) further comprises a third supply channel (5) and between the second supply channel (4) and the third supply channel (5), there is a connecting channel (9) with the neighboring cylinder, in the body (2), this channel opening into the second supply channel (4) upstream of the second drawer (41).