EP0849437B1 - Valve driving arrangement for vehicle engine - Google Patents

Description

The present invention relates to a device for control of a motor vehicle engine valve.

We already know in the prior art a vehicle engine valve control device automobile, of the type comprising a camshaft biasing a valve stem via a latch activated by a corresponding cam of the shaft, the latch having a first end support oscillatingly mounted on a support member carried by a motor support face and a second end of control cooperating with the valve stem, and of the type comprising means for adjusting the height of the member of support relative to the support face.

The height adjustment of the support member allows adjusting the clearance between the latch and the corresponding cam.

There are known means for adjusting the height of the hydraulic type support member, this member forming in this case a hydraulic pusher.

This type of adjustment means has the disadvantage cause unwanted friction between the latch and the corresponding cam.

There are also known means for adjusting height of the supporting member of the cooperating nut type with a threaded part of the support member.

The latter type of adjustment means presents various disadvantages which, depending on the case, arise difficulty accessing the adjusting nut, transmission to the pawl of undesirable efforts during tightening of the nut and the risk of unscrewing it nut.

Also known in document DE-A-4 327 068 a device for controlling a motor vehicle engine valve, of the type comprising a camshaft urging a valve stem through a latch actuated by a corresponding cam of the shaft, the latch comprising a first support end mounted to oscillate on a support member carried by a motor support face and a second cooperating control end with the valve stem, and of the type comprising adjustment means in height of the support member with respect to the support face, in which the member support is slidably mounted parallel to its height on the support face, and what the height adjustment means displaceable substantially perpendicularly at the height of the support member, provided with an adjustment ramp in height cooperating with an additional ramp provided on the support member and, means for immobilizing the means for adjusting the height with respect to to the support face in a desired adjustment position.

The object of the invention is to remedy these drawbacks so as to obtain means of adjustment in space-saving support member height, easily accessible, reliable and simple to manufacture.

To this end, the subject of the invention is a device for controlling a motor vehicle engine valve, of the aforementioned type, characterized in that the support member is slidably mounted parallel to its height on the support face. , and in that the height adjustment means comprise, on the one hand, a movable plate substantially perpendicular to the height of the support member, provided with a height adjustment ramp cooperating with a complementary ramp formed on the support member, and on the other hand, means for immobilizing the plate relative to the support face in a desired adjustment position, said plate being mounted on the support face so as to be movable in rotation about an axis substantially parallel to the height of the support member, the adjustment ramp extending in a helix around the axis of rotation of the plate.

• la platine comporte une première boutonnière, traversée par l'organe d'appui, ménagée dans la rampe de réglage ;
• les moyens d'immobilisation de la platine comprennent une vis de serrage de la platine contre la face-support, traversant une seconde boutonnière de la platine et vissée dans un trou taraudé ménagé dans la face-support
• deux boutonnières sont curvilignes et s'étendent autour de l'axe de rotation de la platine, respectivement dans deux secteurs sensiblement opposés diamétralement;
• la platine comporte une face supérieure dans laquelle est ménagée la rampe de réglage et une face inférieure en appui sur la face-support, l'axe de rotation de la platine étant matérialisé par un pivot, solidaire de la face inférieure de la platine, monté tourillonnant dans un trou ménagé dans la face-support ;
• la platine a une forme générale de disque et comporte sur sa périphérie une encoche ou saillie de manoeuvre destinée à coopérer avec un outil de déplacement de la platine en rotation ;
• l'organe d'appui a une forme générale cylindrique allongée suivant sa hauteur et est immobilisé en rotation autour de son axe par coopération de surfaces complémentaires ménagées sur lui-même et sur un épaulement délimitant la rampe de réglage ;
• l'organe d'appui comporte une partie supérieure, s'étendant au-dessus de la platine, munie d'une extrémité rotulante reliée à la première extrémité du linguet, et une partie inférieure, s'étendant en dessous de la platine, emboítée de façon coulissante dans un trou ménagé dans la face-support ;
• la face-support est une face d'une culasse du moteur.

According to other characteristics of this device:

• the plate comprises a first buttonhole, crossed by the support member, formed in the adjustment ramp;
• the means for immobilizing the plate comprise a screw for clamping the plate against the support face, passing through a second buttonhole of the plate and screwed into a tapped hole formed in the support face
• two buttonholes are curvilinear and extend around the axis of rotation of the plate, respectively in two substantially diametrically opposite sectors;
• the plate has an upper face in which the adjustment ramp is provided and a lower face bearing on the support face, the axis of rotation of the plate being materialized by a pivot, integral with the lower face of the plate, mounted swirling in a hole in the support face;
• the plate has the general shape of a disc and has on its periphery a notch or maneuvering projection intended to cooperate with a tool for moving the plate in rotation;
• the support member has a generally cylindrical shape elongated along its height and is immobilized in rotation about its axis by cooperation of complementary surfaces formed on itself and on a shoulder delimiting the adjustment ramp;
• the support member comprises an upper part, extending above the plate, provided with a swiveling end connected to the first end of the latch, and a lower part, extending below the plate, fitted slidingly in a hole in the support face;
• the support face is one face of an engine cylinder head.

• la figure 1 est une vue en perspective d'un dispositif selon l'invention pour la commande d'une soupape de moteur de véhicule automobile ;
• la figure 2 est une vue de dessus de la figure 1;
• la figure 3 est une vue en coupe suivant la ligne 3-3 de la figure 2;
• la figure 4 est une vue en coupe suivant la ligne 4-4 de la figure 2;
• la figure 5 est une vue en coupe suivant la ligne 5-5 de la figure 3.

The invention will be better understood on reading the description which follows, given solely by way of example and made with reference to the drawings in which:

• Figure 1 is a perspective view of a device according to the invention for controlling a motor vehicle engine valve;
• Figure 2 is a top view of Figure 1;
• Figure 3 is a sectional view along line 3-3 of Figure 2;
• Figure 4 is a sectional view along line 4-4 of Figure 2;
• FIG. 5 is a sectional view along line 5-5 of FIG. 3.

There is shown in the figures a device 10 according to the invention for the control of a valve 12 of internal combustion engine for a motor vehicle.

The device 10 is arranged in a cylinder head 14 of the engine which has been shown an upper face 16 on Figures 3 and 5.

The device 10 comprises a camshaft 18 biasing a valve stem 20 via a latch 22 actuated by a corresponding cam 24 from tree 18.

The latch 22 has a first end support 22A oscillatingly mounted on a support member 26 and a second control end 22B cooperating with the free end of the valve stem 20.

The support member 26 is carried by the upper face 16 of the cylinder head, forming a support and called by the continuation "face-support 16".

The latch 22 also includes a roller 28 of cooperation with cam 24. This roller is rotatably mounted, between the two ends 22A, 22B of the latch, around an axis materialized by a pin 30 substantially parallel to the camshaft 18.

The roller 28 can rotate freely in a center hole 32 of the latch and protrudes outside of this bore 32 to cooperate with the cam 24.

The support member has a generally cylindrical shape elongated according to its height and is mounted on the support face 16 so as to slide parallel to its height, as will be described in more detail by the after.

The control device 10 comprises means 34 for adjusting the height of the support member 26 by relative to the support face 16.

These adjustment means 34 comprise a plate 36 movable substantially perpendicular to the height of the support member 26.

This plate 36 is provided with a ramp 38 of height adjustment cooperating with a complementary ramp 40 formed on the support member 26, as is shown in particular in Figure 4.

The adjustment means 34 also include means 42 for immobilizing the plate 36 by relative to the support face 16 in an adjustment position in desired height.

Preferably, the plate is mounted on the support face 16 so as to be movable in rotation around an X axis substantially parallel to the height of the support member 26.

Thus, in the example illustrated in the figures, plate 36 has the general shape of a delimited disk by two upper faces 36S and lower 36I.

The adjustment ramp 38 is formed in the face upper 36S so as to extend in a helix around the X axis of rotation of the stage.

The lower face 36I is supported on the support face 16.

The axis X of rotation of the plate 36 is materialized by a pivot 44, integrally with the underside 36I of the disc, mounted swiveling in a hole blind 46 formed in the support face 16.

With particular reference to Figure 2, we see that the plate 36 has two buttonholes 48.50 curvilinear, extending around the X axis of rotation of the plate, respectively in two sectors substantially diametrically opposite.

A first buttonhole 48, through which extends the support member 26, is formed in the ramp of setting 38.

It will be noted, with particular reference to the figure 5, that the support member 26 has an upper part 26S, extending above the plate 36, provided with a swivel end connected to the first end 22A of the latch, and a lower part 26I, extending in below this plate 36, slidably fitted in a blind hole 52 made in the support face 16.

The support member 26 is immobilized in rotation around its Y axis by cooperation of curvilinear surfaces 54.56 complementary on itself and on a shoulder delimiting the adjustment ramp 38.

The means 42 for immobilizing the plate 36 preferably include a screw 58 for tightening the plate 36 against the support face 16, crossing the second buttonhole 50 and screwed into a tapped hole 60 formed in the support face 16.

Preferably, the holes 52 and 60, in which are housed respectively the support member 26 and the screw clamp 58, are substantially diametrically opposed relative to the X axis and offset from each other in parallel to the camshaft 18. In this way, the clamping screw 58 is spaced from the cam 24 transversely to the radius means of this cam (see Figure 2). So the position of the tightening screw 58 is independent of the mean radius of cam 24.

Referring to Figures 1 and 2, we see that the plate 36 has a notch on its periphery maneuver 62 intended to cooperate with a conventional tool 64, of complementary shape, intended to move the plate 36 rotating around the X axis.

As a variant, the notch 62 can be replaced by an operating projection intended to cooperate with a appropriate complementary tool.

The plate 36 is manufactured, for example, by a conventional sintering process.

The means 34 for adjusting the height of the member support 26 are very simple to implement.

To obtain a desired adjustment of this height, that is to say to obtain a desired J clearance between the roller 28 and the cam 24 with which it cooperates, it firstly, just loosen the screw 58 in order to allow free rotation of the plate 36 around the X axis.

Then, the plate 36 is rotated by fitting the tool 64 in the notch 62. Due to the cooperation additional adjustment ramps 38.40, the unit support 26 rises or falls to the height desired, depending on the direction of rotation of the plate 36.

During the rotation of the plate 36, the member support 26 and screw 58 move relative to this platinum 36 in the buttonholes 48.50. The support body 26 only moves relatively to the cylinder head 14 longitudinally along its Y axis, by sliding in hole 52 of the cylinder head.

After adjusting the height of the support member 26, the plate 36 is immobilized by clamping against the support face 16 by means of screw 58.

Note that the tightening of the screw 58 does not disturb not the adjustment of the support member 26, because this the latter is separated from screw 58.

It will also be noted that the axes of the organ support 26 and screw 58 being offset between them and, preferably substantially diametrically opposed, the tightening torque exerted on screw 58 produces no undesirable force on the support member 26 or on the latch 22.

The invention is not limited to the embodiment previously described.

In particular, the plate 36 can be moved by translation. In this case, the adjustment ramp and the buttonholes are straight.

The invention has many advantages.

In particular, the height adjustment means of the support member are easily accessible.

Indeed, the support member 26 and the screw tightening 58 being offset between them, the latter is clear to facilitate access to a screwdriver whose positioning and operation can be automated without difficulty.

In addition, the screw 58 being separated from the member support 26, the tightening of this screw is not disturbed by the oscillations of the latch 22.

Claims (9)

1. Driving arrangement (10) for a valve (12) of an automotive vehicle engine, of the type comprising a camshaft (18) which stresses a stern (20) of the valve by means of an arm (22) which is actuated by a corresponding cam (24) of the shaft (18), the arm (22) comprising a first bearing end (22A), which is mounted so as to oscillate on a bearing device (26) which is carried by a support face (16) of the engine, and a second control end (22B) which cooperates with the stem (20) of the valve, and of the type comprising means (34) of adjustment in height of the bearing device (26) with respect to the support face (16), characterised in that the bearing device (26) is mounted so as to slide in a parallel manner to its height on the support face (16), and in that the means (34) of adjustment in height comprise, on the one hand, a plate (36) which is displaceable substantially perpendicularly to the height of the bearing device (26) and is provided with an incline (38) for adjustment in height which cooperates with a complementary incline (40) which is provided on the bearing device (26) and, on the other hand, means (42) for immobilisation of the plate (36) with respect to the support face (16) in a desired adjustment position, said plate (36) being mounted on the support face (16) so as to be displaceable in rotation about an axis (x) which is substantially parallel to the height of the bearing device (22), the adjustment incline (38) extending in a helix about the axis of rotation (X) of the plate.
2. Arrangement according to claim 1, characterised in that the plate (36) comprises a first oblong opening (48) which is traversed by the bearing device (26) and is provided in the adjustment incline (38).
3. Arrangement according to claim 1 or 2, characterised in that the means (42) for immobilisation of the plate (36) comprise a screw (58) for locking the plate against the support face (16), which screw traverses a second oblong opening (50) of the plate and is screwed into a threaded hole (60) which is provided in the support face (16).
4. Arrangement according to claim 3, characterised in that the two oblong openings (48, 50) are curved and extend about the axis of rotation (X) of the plate, respectively in two sectors which are substantially diametrically opposite.
5. Arrangement according to claim 1 or 4, characterised in that the plate (36) comprises an upper face (36S) in which the adjustment incline (38) is provided and a lower face (36I) which abuts on the support face (16), the axis of rotation (X) of the plate (36) being produced by a pivot (44) which is integral with the lower face (36I) of the plate and is mounted so as to swivel in a hole (46) which is provided in the support face (16).
6. Arrangement according to any of the claims 1, 4 or 5, characterised in that the plate (36) has the general form of a disc and comprises on its periphery a control recess (62) or projection which is intended to cooperate with a tool (64) for displacement in rotation of the plate (36).
7. Arrangement according to any of the preceding claims, characterised in that the bearing device (26) has a generally cylindrical form which is elongated in the direction of its height and is immobilised in rotation about its axis (Y) by cooperation of complementary faces (54, 58) which are provided on itself and on a shoulder which delimits the adjustment incline (38).
8. Arrangement according to claim 7, characterised in that the bearing device (26) comprises an upper part (26S), which extends above the plate (36) and is provided with an end connected as a ball joint to the first end (22A) of the arm, and a lower part (26I) which extends below the plate (36) and is fitted in a sliding manner in a hole (52) which is provided in the support face (16).
9. Arrangement according to any of the preceding claims, characterised in that the support face (16) is a face of a cylinder head (14) of the engine.

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