T 1100/09 – For The Worse

This is an appeal of the opponent (alone) against the decision of the Opposition Division (OD) to maintain the opposed patent in amended form.

Claim 1 as maintained by the OD read:

A piston assembly for heavy duty diesel engine applications comprising:

a one piece upper crown part (102, 202) and a one piece lower crown part (104, 204);

said upper crown part (102, 202) having a lower connecting portion formed with an inner annular rib (107, 207) and an outer annular rib (109, 209) spaced from said inner rib (107, 209),

said inner and outer ribs (107, 207, 109, 209) of said upper crown part (102, 202) extending axially to free ends thereof each presenting a single planar joining surface (108, 110, 208, 210) of said upper crown part ribs (107, 207, 109, 209);

said lower crown part (104, 204) having an upper connecting portion (117, 217) from which a pair of pin boss portions (121, 221) depend having a space (127, 227) between said pin boss portions (121, 221) to receive a connecting rod, said upper connecting portion (117, 217) having an inner annular rib (113, 213) and an outer annular rib (115, 215) spaced from said inner annular rib (113, 213) of said lower crown part (104, 204),

said inner and outer ribs (113, 213, 115, 215) of said lower crown part (104, 204) extending axially to free ends thereof each presenting a single planar joining surface (116, 118, 216, 218) of said lower crown part ribs (113, 213, 115, 215);

said lower crown part (104, 204) having an inner gallery floor (106d, 206d) arranged above said space (127, 227) of said pin boss portions (121, 221) and surrounded by said inner annular rib (113, 213) of said lower crown part (104, 204); and

said inner gallery floor (106d, 206d) including an opening (106e, 206e) establishing fluid communication between said inner gallery (120, 220) and said space (127, 227) between said pin boss portions (121, 221)

characterized in

that said inner and outer ribs (107, 207, 109, 209) of said upper crown part (102, 202) are joined to said inner and outer ribs (113, 213) of said lower crown part (104, 204), respectively, across their respective single planar joining surfaces (108, 110, 208, 210, 116, 118, 216, 218) by friction weld joints (106b, 106g, 206b, 206g) to define the inner oil gallery (120, 220) and the outer oil gallery (122, 222) within the joined crown parts (102, 202, 104, 204) separated by said inner ribs (107, 113, 207, 213) of said joined crown parts (102, 202, 104, 204),

that said inner rib (113, 213) of said lower crown part (104, 204) is formed with at least one fluid transfer port (123, 223) spaced axially from said joining surface thereof

and extending between said outer oil gallery (122, 222) and said inner oil gallery (120, 220) to establish fluid communication therebetween,

that said fluid transfer port (123, 223) of said inner rib (113, 213) extends upwardly at an angle from said outer gallery (122, 222) to said inner gallery (120, 220),

that said outer gallery (122, 222) has a floor (124, 224) extending between said inner rib (113, 213) and said outer rib (115, 215) that is spaced axially from said planar joining surfaces (116, 118, 216, 218) of said inner and outer ribs (113, 213, 115, 215) of said lower crown part (104, 204), (and)

that said floor (124, 224) of said outer gallery (122, 222) is spaced below said floor (106d, 206d) of said inner gallery (120, 220). (my emphasis)

Claim 1 of the auxiliary request read (changes have been made apparent)

A piston assembly for heavy duty diesel engine applications comprising:

a one piece upper crown part (102, 202) and a one piece lower crown part (104, 204);

said upper crown part (102, 202) having a lower connecting portion formed with an inner annular rib (107, 207) and an outer annular rib (109, 209) spaced from said inner rib (107, 209),

said inner and outer ribs (107, 207, 109, 209) of said upper crown part (102, 202) extending axially to free ends thereof each presenting a single planar joining surface (108, 110, 208, 210) of said upper crown part ribs (107, 207, 109, 209);

said lower crown part (104, 204) having an upper connecting portion (117, 217) from which a pair of pin boss portions (121, 221) depend having a space (127, 227) between said pin boss portions (121, 221) to receive a connecting rod, said upper connecting portion (117, 217) having an inner annular rib (113, 213) and an outer annular rib (115, 215) spaced from said inner annular rib (113, 213) of said lower crown part (104, 204),

said inner and outer ribs (113, 213, 115, 215) of said lower crown part (104, 204) extending axially to free ends thereof each presenting a single planar joining surface (116, 118, 216, 218) of said lower crown part ribs (113, 213, 115, 215);

said lower crown part (104, 204) having an inner gallery floor (106d, 206d) arranged above said space (127, 227) of said pin boss portions (121, 221) and surrounded by said inner annular rib (113, 213) of said lower crown part (104, 204); and

said inner gallery floor (106d, 206d) including an opening (106e, 206e) establishing fluid communication between said inner gallery (120, 220) and said space (127, 227) between said pin boss portions (121, 221)

characterized in

that said inner and outer ribs (107, 207, 109, 209) of said upper crown part (102, 202) are joined to said inner and outer ribs (113, 213) of said lower crown part (104, 204), respectively, across their respective single planar joining surfaces (108, 110, 208, 210, 116, 118, 216, 218) by friction weld joints (106b, 106g, 206b, 206g) to define the inner oil gallery (120, 220) and the outer oil gallery (122, 222) within the joined crown parts (102, 202, 104, 204) separated by said inner ribs (107, 113, 207, 213) of said joined crown parts (102, 202, 104, 204),

that said inner rib (113, 213) of said lower crown part (104, 204) is formed with at least one fluid transfer port (123, 223) spaced axially from said joining surface thereof

and extending between said outer oil gallery (122, 222) and said inner oil gallery (120, 220) to establish fluid communication therebetween,

that said fluid transfer port (123, 223) of said inner rib (113, 213) extends upwardly at an angle from said outer gallery (122, 222) to said inner gallery (120, 220),

that said fluid transfer port (123, 223) extends from a location above said floor (124, 224) of said outer gallery (122, 222) to said floor (106d, 206d) of said inner gallery (120, 220) at said upward angle,

that said outer gallery (122, 222) has a floor (124, 224) extending between said inner rib (113, 213) and said outer rib (115, 215) that is spaced axially from said planar joining surfaces (116, 118, 216, 218) of said inner and outer ribs (113, 213, 115, 215) of said lower crown part (104, 204), (and)

that said floor (124, 224) of said outer gallery (122, 222) is spaced below said floor (106d, 206d) of said inner gallery (120, 220), and

that said inner ribs (107, 113, 207, 213) of said upper and lower crown parts (102, 202, 104, 204) extend substantially parallel to a central longitudinal axis A of said upper and said lower crown parts (102, 202, 104, 204) adjacent said joining surfaces (116, 118, 216, 218, 108, 110, 208, 210).

This case offers us the opportunity to study one of those cases where the Boards accepts reformatio in peius.

Main request (A 84 EPC 1973)

[2.1] The [patent proprietor] was of the opinion that the insertion of “single” into claim 1 made during the opposition proceedings was only a clarification which did not restrict the claimed subject-matter. The Board however finds that the amendment is a restriction; it excludes for example multi-planar surfaces. The amendment is thus not simply a clarification of what the granted claim already states as argued by the [patent proprietor]. As the amendment is also not simply a result of combining granted claims, the requirements of A 84 EPC 1973 need to be fulfilled by the amendment.

[2.2] The features in the pre-characterizing portion of claim 1 define two crown parts of a piston assembly to be joined by friction welding (i.e. to achieve the welded state defined in the characterizing portion). However, the claim is directed to a “piston assembly” (i.e. an assembly formed by assembling these crown parts) in which the friction welded joining surfaces are no longer identifiable because the surfaces have melted and are welded to one another. Consequently the features of the pre-characterizing portion in question are no longer present in the subject-matter having the further features of the characterizing portion. This leads to a lack of clarity in the meaning of A 84 EPC 1973 since it is not determinable in which configuration the respective joining surfaces are related to one another in the piston assembly according to claim 1. Specifically in the present case, it is no longer possible to identify whether a single surface was used on each rib before welding. Although the [patent proprietor] argued that a single surface on each rib could still be identified in the welded assembly, as allegedly demonstrated by Annex A, the Board is unconvinced by this argument, since the joining surfaces where friction welding occurred in Annex A are highly deformed (as shown for example at the outer portions thereof) such that identification of a single surface on each of the contact areas which were ultimately joined cannot be made.

[2.3] For this reason the main request cannot be allowed.

Auxiliary request (exception to the prohibition of reformatio in peius)

[3.1] In its decision G 1/99 the Enlarged Board of Appeal held that in principle, an amended claim, which would put the opponent and sole [opponent] in a worse situation than if it had not appealed, must be rejected. However, an exception to this principle may be made in order to meet an objection put forward by the opponent/[opponent] or the Board during the appeal proceedings, in circumstances where the patent as maintained in amended form would otherwise have to be revoked as a direct consequence of an inadmissible amendment held allowable by the OD in its interlocutory decision.

In such circumstances, in order to overcome the deficiency, the patent proprietor/[patent proprietor] may be allowed to file requests, as follows:

• in the first place, for an amendment introducing one or more originally disclosed features which limit the scope of the patent as maintained;
• if such a limitation is not possible, for an amendment introducing one or more originally disclosed features which extend the scope of the patent as maintained, but within the limits of A 123(3);
• finally, if such amendments are not possible, for deletion of the inadmissible amendment, but within the limits of A 123(3).

[3.2] In the present case neither the Board nor the parties to the proceedings saw a possibility of applying one of the first or second alternative solutions established by the Enlarged Board. The newly introduced term “single” cannot be restricted by another expression since it has already the narrowest specific meaning in defining the surfaces. There is no other expression in the patent which would be suitable to restrict “single” in another way because it is already the highest degree of definition compared to the possibilities of “a” or “one”. Therefore, according to established case law, the [patent proprietor] may be allowed to delete the inadmissible amendment made during the opposition proceedings. Since the deletion also does not extend the scope of protection conferred by claim 1 as granted (as this defined merely “a planar joining surface”), deletion of the term “single” does not contravene A 123(3).

Finally the case was remitted to the first instance for further prosecution.

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