EP0013847A1 - An internal-combustion engine poppet valve cage cooled by a circulating refrigerant fluid, especially for an engine comprising two outlet valves per cylinder, and method of mounting such a cage - Google Patents

Abstract

The invention relates to a valve cover for an internal combustion engine. This chapel is characterized in that it is produced in at least two complementary pieces respectively upper (14) and lower (16) with transverse joint plane (17) cutting the partition (10) longitudinal of the annular cavity 9 of the guide valve (2). This chapel further comprises an intermediate element (17) interposed between the upper part (14) and the lower part (16). This element (17) has at least two openings (19, 20) allowing suitable circulation of the coolant between the upper (21; 22) and lower (23; 24) parts of the same compartment (9a; 9b) of the cavity 9 and arranged so as to avoid any direct communication of the coolant between the inlet (9a) and return (9b) compartments of the coolant for at least two different angular positions of said two parts. The invention applies in particular to engines comprising two exhaust valves, and therefore two chapels, per cylinder, making it possible to use the same lower part 16 for the chapels on the left and on the right mounted on the cylinder.

Description

The present invention essentially relates to a mushroom valve chapel cooled by circulation of a coolant, for internal combustion engine.

More particularly, the present invention relates to a mushroom valve chapel cooled by circulation of a coolant for an internal combustion engine comprising two exhaust valves per cylinder as well as a method of mounting such a chapel.

Are already known mushroom valve chapels cooled by circulation of a coolant, for internal combustion engine, which include a cage with at least one veil or arm having a lateral orifice for communication with an inlet or outlet channel gases in or out of the cylinder on which said chapel is mounted, said web supporting at its end an annular valve seat containing an annular chamber for said refrigerant; as well as a guide to valve comprising an annular cavity for their coolant separated by a longitudinal partition into at least two compartments respectively of inlet and return of said coolant. Furthermore, the veil is pierced longitudinally of at least two conduits respectively leading to said cavity and said chamber. In addition, one of said conduits ends in the bottom of one of the two compartments and the other conduit ends in the bottom of the other compartment, in order to ensure correct circulation of the coolant.

However, when such chapels are used in engines comprising two exhaust valves per cylinder and therefore two chapels respectively on the right and on the left, the angular position of the abovementioned lateral orifice of each chapel on the right or on the left must be different in order to end up with a single cylinder exhaust gas outlet channel. On the other hand, in most cases, although the upper part forming the valve guide of the left chapel is symmetrical with the upper part forming the valve guide of the right chapel, the lower part forming the cage of the chapel of left can be identical to that of the right chapel provided that the above orientation of the lateral opening is respected.

The major drawback of the valve chapels known up to now consists in that the aforementioned orientation of the lateral orifice for communication with the exhaust gas outlet channel outside the cylinder on which said chapel is mounted cannot be obtained by making two different shaped parts forming a cage in the foundry, one intended to be adapted to the valve guide part of the left chapel and the other intended to be adapted to the valve guide part of the right chapel. The cost of the chapels finally obtained is therefore relatively high.

The present invention therefore aims to remedy the aforementioned drawback by providing a solution which allows the use of a single piece forming a cage adaptable both to the part forming the valve guide of the chapel on the left and to that of the chapel. right of an internal combustion engine with two exhaust valves per cylinder. Preferably, this solution must be of particularly simple design.

This solution consists, according to the invention, in a mushroom valve chapel cooled by circulation of a cooling fluid, for internal combustion engine, in particular for engine comprising two exhaust valves per cylinder, of the type previously described, characterized in that it is made of at least two complementary parts respectively upper and lower with transverse joint plane cutting said longitudinal partition, and in that it comprises an intermediate element interposed between said upper part and said lower part, said element comprising at at least two openings allowing adequate circulation of the coolant between the upper and lower parts of the same compartment and arranged so as to avoid any direct communication of coolant between the coolant inlet and return compartments for at least two positions different angles of said two parts.

Thanks to this structure of the valve chapel, the same lower part can be used for the aforementioned left chapel and the right chapel since it is possible to obtain the correct angular orientation of the aforementioned lateral orifice of each chapel. along the axis of the exhaust gas outlet channel out of the cylinder by simple rotation of the lower part relative to the upper part. the intermediate element for achieving the correct circulation of the refrigerant.

This makes it possible to make a significant saving relative to the previous methods according to which the lower part forming the cage of the left chapel had a different shape from the lower part forming the cage of the right chapel. This therefore results in a significant reduction in the cost of production of the chapels.

According to a particularly advantageous embodiment, the intermediate element is substantially planar and advantageously consists of a washer whose two aforementioned openings are radially arranged and extend in an arc of circle less than 180 ° C.

Advantageously, the two aforementioned openings are arranged substantially symmetrically with respect to the center of symmetry of said intermediate element.

According to a preferred embodiment, each aforementioned opening is radially arranged and extends in an arc of circle of between approximately 135 ^c and 180 °, which allows a shift of the respective angular positions of the two upper and lower parts of between 0 and 45 °.

On the other hand, in the case where the valve chapel is a right chapel of an engine comprising two exhaust valves respectively on the left and on the right per cylinder, the lower part has an angular offset of approximately 22 to 25 °, preferably 23 ° 30 relative to the normal angular position of the lower part relative to the upper part without intermediate element.

In the case of a valve chapel for the chapelle on the left of an engine comprising two exhaust valves respectively on the left and on the right per cylinder, the lower part has an angular offset of approximately 40 to 43 °, preferably 41 , 30 °, relative to the normal angular position of the lower part relative to the upper part, without any intermediate element. Thus, it can be seen that the valve chapel according to the present invention has great adaptability since it is possible to vary the angular position of the lower part relative to the upper part, and therefore the angular position of the lateral orifice. communication with the exhaust gas outlet channel, between very different values ranging from 0 to 45 °. In this regard, it should be noted that these valve chapels can also be adapted to the case of engines comprising two intake valves per cylinder, these engines also comprising two chapels on the left and on the right for each cylinder communicating with a single channel d gas admission into the cylinder, which is particularly advantageous.

The invention also relates to engines having at least two intake or exhaust valves per cylinder comprising two chapels respectively of corresponding right and left, with lateral orifice for communication with a single gas inlet or outlet channel into or out of said cylinder, characterized in that said chapels are constituted by chapels according to the invention as defined above, of which the upper parts of the left and right respectively are symmetrical while the lower part of the chapel on the left is identical to that of the chapel on the right.

Advantageously, as mentioned above, the lower part of the right chapel has an angular offset of 22 to 25 °, preferably 23 ° 30, relative to the normal angular position of the lower part relative to the upper part, without any intermediate element. and, similarly, the chapel on the left has an angular offset of around 40 to 43 °, preferably 41.30 °.

Finally, the present invention relates to a method of mounting a valve cap according to the invention, characterized in that it consists in securing, for example by welding or brazing the intermediate element with one of the upper or lower parts aforementioned so that each opening is arranged on either side of the plane of the longitudinal partition of the cavity of said part and then to be joined, for example by welding or brazing, the other of said upper or lower parts with the assembly upper or lower intermediate element-part, with a predetermined angular offset of between 0 and 45 ° relative to the normal position of said parts without intermediate element.

Other purposes, features and benefits of the invention will appear more clearly in the light of the explanatory description which follows, made with reference to the appended drawings representing a currently preferred embodiment of a valve cap according to the invention, given solely by way of example.

Figure 1 is a cross-sectional view of a cylinder of an engine comprising two exhaust valves and therefore two exhaust chapels according to the invention, the lateral orifice leading to a single outlet channel for the gases exhaust. The cut is made at the level of the valve caps, the valves having been removed for greater clarity; Figure 2 is a sectional view along line II-II of Figure 1 said section being folded down; Figure 3 is a sectional view along line III-III of Figure 2; Figure 4 is a sectional view similar to that of Figure 3, showing the chapel on the right, the position of the upper part of said chapel being shown in phantom lines; FIG. 5 is a sectional view along the line V-V of FIG. 2.

With reference to FIGS. 1 to 5, and more particularly to FIG. 2, a mushroom valve chapel cooled by circulation of a cooling fluid, for an internal combustion engine, comprises a cage 1 and a valve guide 2. To facilitate understanding of the drawing, the valve, which comes to be fitted by its rod in the chapel, has not been shown.

The chapel 1 comprises at least one veil 3 or arm comprising a lateral orifice 4 for communication with an inlet or outlet channel 5 (see FIG. 1) for gases into or out of the cylinder 6 on which the chapel is mounted. The web 3 supports at its end • an annular valve seat 7 containing an annular chamber for said refrigerant. The valve guide 2 comprises an annular cavity 9 for the coolant separated by a longitudinal partition 10 (see FIGS. 3 and 5) into at least two compartments 9a, 9b respectively for inlet (compartment 9a) and return (compartment 9b ) refrigerant.

The web 3 is pierced longitudinally with at least two conduits, such as the conduits 11, 12, (FIG. 5) leading respectively to the cavity 9 and to the chamber 8. One (11) of said two conduits (11, 12 ) ends in the bottom of one (9a) of the two compartments (9a, 9b) and the other conduit (12) ends in the bottom of the other compartment (9b).

According to the present invention, this valve chapel is made of at least two complementary pieces, respectively upper 14 and lower 16 with transverse joint plane 15 cutting said longitudinal partition 10 into a portion of upper partition 10a and a portion of lower partition 10b. Furthermore, this chapel according to the invention comprises an intermediate element 17 interposed between the upper part 14 and the lower part 16. This intermediate element 17 has at least two openings 19 and 20 as seen in Figure 3, allowing a suitable circulation of the coolant between the upper (21; 22) and lower (23; 24) parts of the same compartment (9a; 9b). These openings 19, 20 are arranged so as to avoid any direct communication of coolant between the inlet compartments 9a and 9b return of the refrigerant for at least two different angular positions of said two parts, as can be seen in Figures 3 ef4.

Preferably, the intermediate element is substantially planar, and advantageously consists of a washer, the two openings 19, 20 of which are radially disposed and extend in an arc of circle less than 180 ° C. as can be seen in FIGS. 3 and 4.

According to a particularly advantageous embodiment, the two openings 19, 20 are arranged substantially symmetrically with respect to the center of symmetry C (FIG. 3) of the intermediate element 17.

Advantageously, each opening 19, 20 is radially arranged and extends in an arc of circle of between approximately 135 ° and 180 °, which allows an offset ( ⁰ (Figure 3; or β, Figure 4) of the respective angular positions of the two upper 14 and lower 16 pieces between 0 and 45 °.

Furthermore, when the chapel according to the invention is intended to form the right chapel 30 of an engine comprising two exhaust valves respectively on the left and on the right per cylinder 6 and therefore two chapels 30, 31, the lower part 16 advantageously has an angular offset / 3 (see FIG. 4) of approximately 22 to 25 °, preferably 23.30 ° (as shown) relative to the normal angular position of the lower part 16 relative to the upper part 14 without element intermediate.

Similarly, when the chapel according to the invention is intended to form the left chapel 31 of such engine with two exhaust valves per cylinder. the lower part 16 advantageously has an angular offset (α, FIG. 3) of approximately 40 to 43 °, preferably 41.30 ° (as shown) relative to the normal angular position of the lower part 16 relative to the part upper 14, without intermediate element 17.

The valve chapels according to the invention therefore have the main application of engines having at least two intake or exhaust valves per cylinder 6 (FIG. 1) comprising two corresponding chapels respectively on the right 30 and on the left 31, with lateral orifice , such as 4, for communication with a single channel 5 for inlet or outlet (in the case shown) of gases into or out of the cylinder. In this case, the chapels 30, 31 are constituted by chapels according to the invention, the upper parts of the left 14 and the right respectively 14 ′ are symmetrical while the lower part 16 of the left chapel is identical to that of the chapel of right.

It should be noted that in Figure 4, the upper part 14 'of the right chapel 30 uses the same reference numbers as those of the upper part 14 of the left chapel 31 with a prime index to differentiate them. Thus, the longitudinal partition of the upper part 14 'is indicated 10' and corresponds to the part 10a (Figure 3). 0

The invention therefore makes it possible to use the same lower part 16 forming a cage for the left-hand chapel or the right-hand chapel, which makes it possible to lower the production cost of the valve chapels by greater standardization of the foundry parts. to achieve. Another advantage of this construction consists in that these chapels have a great adaptability since it is possible to vary the angular position of the lower part 16 relative to the upper part 14 between wide limits between 0 and 45 °.

Of course, the upper part 14, the intermediate element 17 and the lower part 16 are invariably linked to the assembled state, for example by welding or brazing in a manner known per se. Then. each chapel is mounted on a cylinder 6 (FIG. 1) by means such as 32, 33, 32 ', 33' allowing suitable fixing in the cylinder head of the engine.

The invention also relates to a method of mounting the aforementioned valve cap characterized in that it consists in securing, for example by welding or brazing, the intermediate element 17 with one (16) of the upper parts 14 or lower 16 above so that each opening 19, 20 is disposed on either side of the plane of the longitudinal wall 10 of the cavity 9 of said part (16) and then to be joined, for example by welding or brazing, the other (14) of said upper 14 and lower 16 parts with the intermediate element 17-upper or lower part assembly (in the case shown it is the lower part 16), with an angular offset (α, FIG. 3; β, FIG. 4) predetermined between 0 and 45 ° relative to the normal position of said upper 14 and lower 16 parts without intermediate element 17.

It is understood that the offset of an angle CK of the partition 10 between the upper part 14 and the lower part 16 corresponds to an identical offset of the position of the lateral orifice 4, which makes it possible to adapt the position of this lateral orifice 4 along the axis of the exhaust gas outlet channel 5 out of the cylinder 6 on which the chapel is mounted, as shown in the figure 1.

Furthermore, if it is a question of mounting a right-hand chapel of an engine comprising two exhaust valves per cylinder, that is to say two chapels 30, 31 per cylinder 6 (FIG. 1), the angular offset A is between 22 ° and 25 °, preferably is equal to 23.30 ° as shown in FIG. 4. Similarly, in the case of a chapel on the left, this angular offset α is advantageously between 40 and 43 °, preferably is equal to 41.30 ° as shown in Figure 3.

It should be noted that various modifications can be made to this chapel. Thus, the annular chamber 8 can be formed by the assembly of an added piece 34 on the web 3 according to a transverse joint plane 35, in order to facilitate the construction of said chapel.

Likewise, the invention is in no way limited to the embodiment described and shown, which has been given only by way of example. In particular, it includes all the means constituting technical equivalents of the means described as well as their combinations if these are carried out according to the spirit and within the scope of the claims which follow.

Claims (10)

1. Chapel of mushroom valve cooled by circulation of a coolant, for internal combustion engine, in particular for engine comprising two exhaust valves per cylinder, of the type comprising a cage with at least one veil or arm comprising a lateral orifice communicating with a gas inlet or outlet channel into or out of the cylinder on which said chapel is mounted, said web supporting at its end an annular valve seat containing an annular chamber for said refrigerant; and a valve guide comprising an annular cavity for said coolant separated by a longitudinal partition into at least two compartments respectively of inlet and return of said coolant, said veil being pierced longitudinally of at least two conduits leading respectively to said cavity and to said chamber, one of said two conduits terminating in the bottom of one of the two compartments and the other conduit terminating in the bottom of the other compartment, characterized in that it is produced in at least two pieces complementary respectively upper and lower to transverse joint plane cutting said longitudinal partition, and
in that it comprises an intermediate element interposed between said upper part and said lower part, said element comprising at least two openings allowing suitable circulation of the coolant between the upper and lower parts of the same compartment and arranged so as to avoid any direct communication of refrigerant between the inlet and return compartments of the refrigerant for at least two different angular positions of said two parts. 2. Chapel according to claim 1, characterized in that the intermediate element is substantially planar and advantageously consists of a washer whose two aforementioned openings are radially arranged and extend in an arc of circle less than 180 ° C. 3. Chapel according to claim 1 or 2, characterized in that the two aforementioned openings are arranged substantially symmetrically relative to the center of symmetry of said intermediate element. 4. Chapel according to one of the preceding claims, characterized in that each aforementioned opening is radially arranged and extends in an arc of circle between about 135 ° and 180 °, which allows a shift of the respective angular positions of said parts upper and lower between 0 and 45 °. 5. Chapel according to one of the preceding claims, for the right chapel of an engine comprising two exhaust valves respectively on the left and on the right, per cylinder, characterized in that the lower part has an angular offset of approximately 22 at 25 °, preferably 23.30 ° relative to the normal angular position of the lower part relative to the upper part without any intermediate element. 6. Chapel according to one of the preceding claims, for the left chapel of an engine comprising two exhaust valves respectively on the left and on the right per cylinder, characterized in that the lower part has an angular offset of approximately 40 to 43 °, preferably 41.30 ° from the normal angular position of the lower part relative to the upper part without intermediate element. 7. Engine having at least two intake or exhaust valves per cylinder comprising two corresponding chapels on the right and left respectively with lateral orifice for communication with a single gas intake or outlet channel in or out of the cylinder, respectively,
characterized in that said chapels are constituted by chapels according to one of the preceding claims, the upper parts of the left and right respectively are symmetrical while the lower part of the left chapel is identical to that of the right chapel. 8. Motor according to claim 7,
characterized in that the lower part of the right chapel has an angular offset of 22 to 25 °, preferably 23.30 ° with respect to the normal angular position of the lower part relative to the upper part without an intermediate element while the lower part of the left chapel has an angular offset of 40 to 43 °, preferably 41.30 ° with respect to the normal angular position of the lower part relative to the upper part without intermediate element. 9. A method of mounting a valve chapel according to any one of claims 1 to 6, characterized in that it consists in securing, for example by welding or brazing, the intermediate element with one of the upper parts or lower above so that each opening is disposed on either side of the plane of the longitudinal wall of the cavity of said part and then to be joined, for example by welding or brazing, the other of said upper and lower parts with the intermediate element-upper or lower part assembly, with a predetermined angular offset of between 0 and 45 ° relative to the normal position of said parts without intermediate element. 10. Method according to claim 9, characterized in that, in the case of a straight chapel, the aforementioned angular offset is from 22 to 25 °, preferably 23.30 °, while in the case of a chapel on the left, the aforementioned angular offset is from 40 to 43 °, preferably 41.30 °.

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