T 0839/05 05-10-2006

Reasons for the Decision

1. The appeal is admissible.

2. Main request - patent as granted

2.1 The state of the art in accordance with Article 54(2) EPC comprises the arrangement, generally referred to as D1, of a tool body as shown in document D1e (Plattensitz P2200-2-C) in combination with an insert as shown in document D1f (Wendeplatte P 22215-2), which was made available to the public by undisputed prior use.

2.2 Using the wording of claim 1 of the patent in suit, this arrangement comprises an anti-rotation mounting mechanism between an indexable insert and an insert-receiving pocket in a tool body, said insert including (see D1f) an upper surface that terminates in a cutting edge, a lower surface, and a circular side surface between said upper and lower surfaces, comprising:

a plurality of stop surfaces disposed around said insert side surface, a portion of which is obliquely oriented with respect to said side surface of said insert (see D1f, lowest drawing); at least one anti-rotation means (see the pin designated "Zylinderstift" in D1e) in said pocket of said tool body for engaging said obliquely oriented portion of said curved stop surfaces forming an interference joint; wherein said stop surfaces are curved and both said surfaces and anti-rotation means are substantially defined by a partial radius curve.

In the known arrangement, each stop surface is provided by a recess defined by a portion of a circle (see the front view of the insert in D1f) and the anti-rotation means is provided by a cylindrical pin (see D1e) which has a radius slightly smaller than that of the recess.

It is undisputed that, since it is an edge of the pin that contacts the recess, the contact between the pin and the recess occurs, in theory, at a point, and that in practice, due to the unavoidable deformation of the materials, the contact occurs along a line extending along the edge of the pin.

The appellant submitted that since an edge was not a surface, D1 did not disclose that it was a stop surface that engaged the anti-rotation surface. However, an edge created by the intersection of two surfaces is, by definition, a line common to both surfaces. Accordingly, the edge of the pin is part of the cylindrical surface of the pin, and therefore the above mentioned anti-rotation means can effectively be regarded as an anti-rotation surface.

2.3 It follows from the above that the novelty of the subject-matter of claim 1 depends on whether the claim refers to the contact which occurs in theory or that which occurs in practice.

2.4 The patent in suit discloses that the curved stop surfaces and anti-rotation surfaces are "relatively gently sloping" (see col. 5, last three lines). Figs. 4 and 5 clearly and unambiguously disclose that these surfaces have different inclinations. The theoretical contact between such round surfaces having different inclinations as shown in Fig. 4 to 6 can, however, only be a point, not a line.

The appellant submitted that Figures 4 and 5 represented cross-sectional views taken at a distance from where the contact between the stop surface and the anti-rotation surface occurred, and that at that location, these surfaces were parallel. This interpretation is neither corroborated by geometrical explanations nor finds any support in the description. In fact, either the curved surfaces are parallel along their entire extension, but then there would be no different inclinations in the cross-sectional views of Figs. 4 and 5, or at least one of them has a varying inclination such that parallelism is given at the contact location only. However, there is no indication in the disclosure of the patent in suit taken as a whole to support the latter specific construction of surfaces. Moreover, the statement in the description (col. 5, lines 50 to 56) according to which "oblique contact refers to the fact that a line C1, C2 drawn tangent to the engagement portions 37a, 58a traverses the outer circumference of the circular insert 15 at an angle which is non-orthogonal to the outer circumference of the circular insert 3" rather suggests that the line contact does not occur in a substantially vertical direction (as seen in the view of Fig. 4) but rather along the horizontal oblique lines C1 and C2, as shown in Fig. 6. However, even in the horizontal plane of Fig. 6 there is no theoretical line contact, since the curved lines representing the profile of the curved surfaces 35 and 36 can in theory only contact each other at a point (although in practice they are in contact along a line). Finally, the fact that appellant itself provided two different interpretations of Fig. 5, is an indication that the geometrical representation of Fig. 5 has a certain degree of ambiguity.

The appellant further submitted that a clear distinction was made in the patent in suit between the definition in the claims, stating that there was line contact, and the result in practice, which was described as a broad line or lenticular contact. However, the claims refer to "at least line contact" and the description does not mention a "line contact" but only discloses a "broad line or lenticular contact" (column 3, lines 4, 5 and 24, 25; column 6, lines 1,2). The latter type of contact falls under the generic definition of "at least line contact" and is, undisputedly, the type of contact that occurs in practice in the embodiments described in the patent in suit. Therefore, there is no basis in the patent in suit to conclude that the terminology in the claims refers to the theoretical contact whilst that of the description to the contact that occurs in practice.

It follows that the patent in suit does not clearly and unambiguously disclose a theoretical line contact, but only a line contact as the contact which occurs in practice.

Furthermore, by reciting that the stop surfaces and the anti-rotation surface "engage in at least line contact in forming said interference joint", claim 1 of the patent in suit (and analogously independent claim 10 as well) refers to the situation in which the surfaces are engaged and the interference joint is formed, hence to a situation in which each surface applies a force to the other. In an anti-rotation mounting mechanism of the kind claimed, the different situation in which an interference joint, in the sense of a positive locking of one surface respect to the other, exists without any application of a force is rather hypothetical and certainly not maintained in use when external forces act on the insert. Accordingly, claim 1 taken alone can only be seen as relating to a situation which occurs in practice, not in theory.

2.5 It follows from the above that the information in the patent in suit only allows claim 1 to be understood as referring to the contact which occurs in practice. Since, as explained above, in D1 such contact is "at least along a line", the subject-matter of claim 1 lacks novelty and therefore the main request of the respondent cannot be allowed due to lack of novelty (Art. 54(2) EPC).

3. The auxiliary requests

The non-allowance of the main request implies that the decision of the Opposition Division according to which the claimed subject-matter was both novel and inventive must be set aside and the auxiliary requests taken into consideration.

The amendments according to the auxiliary requests consist principally in the inclusion, in the independent granted claims, of additional features which are different for each auxiliary request. This means that, assuming that novelty is present, the assessment of inventive step must be made on a substantially different basis for each auxiliary request.

It has been acknowledged in the jurisprudence of the Boards of Appeal that there is no absolute right of a party to have every aspect of a case examined in two instances (see e.g. T 133/87, point 2. of the reasons), even if as a consequence the patent is revoked for the first time by the Board of Appeal (see e.g. T 557/94, point 1.3 of the reasons). Other criteria, e.g. the general interest that proceedings are brought to a close within an appropriate period of time, have also to be taken into account by the Board when deciding whether or not to remit a case. In the present case, since the amendments are of a different nature for each auxiliary request, a possible consequence of remittal could be further remittals on subsequent appeal proceedings, which would unduly lengthen the proceedings. Thus, with due consideration made for procedural economy and to avoid further delay, the Board decides not to remit the case but to decide on it itself in accordance with Article 111(1) EPC.

4. Auxiliary request II

4.1 Claim 1 of auxiliary request II includes all the features of granted claim 1 and, additionally, the feature of granted claim 6 according to which "said anti-rotation surface is substantially complementary to said curve of said stop surfaces".

4.2 As explained above (point 2.2), in the prior used arrangement each stop surface is provided by a recess defined by a portion of a circle and the anti-rotation surface is provided by a cylindrical pin which has a radius (2 mm: see the indication "Ø4" for the diameter of the pin in D1e) slightly smaller than that of the recess (the radius of the recess is about 2.1 mm, see the indication R2,1 in D1f, whereby the difference between the radiuses is 0.1 mm). When comparing D1e and D1f, it is clear that the surface of the recess which contacts the pin is inclined at an angle of 7º with respect to the cylindrical surface of the pin. Accordingly, the surface of the recess and the cylindrical surface of the pin are not identical, and thus not perfectly complementary. However, the expression "substantially complementary" in claim 1 can only be regarded as requiring that the two surfaces are approximately complementary, since as shown in Fig. 6, they have different inclinations (see also point 2.3 above). Since the relevant surfaces of the pin and the recess in D1 only differ by a very small amount in radius and inclination, they are approximately complementary.

It follows that D1 discloses, in combination, all the features of claim 1 according to auxiliary request II.

4.3 Therefore, auxiliary request II is not allowable due to lack of novelty (Article 54(2) EPC).

5. Auxiliary request III

5.1 Claim 1 of auxiliary request III includes all the features of granted claim 1 and, additionally, the feature of granted claim 2 according to which "said anti-rotation surface is an integral part of a lower side surface of said pocket".

5.2 In D1, as is evident from D1e, the anti-rotation surface provided by the pin is integrated in a lower side surface of the insert-receiving pocket. However, since the pin is provided as a separate component, it is not an integral part of a lower side surface of the pocket, whereby the expression "integral part" can only be understood in the context of the patent in suit (see e.g. Fig. 2A) as meaning that the anti-rotation surface is structurally formed as a unit with the pocket.

Therefore, the added feature confers novelty to the subject-matter of claim 1 with respect to the arrangement in D1.

5.3 The respondent submitted that the provision of the anti-rotation surface as an integral part of a lower side surface of said pocket allowed a more accurate positioning of the insert in the insert-receiving pocket. However, there is no disclosed basis in the patent in suit to support this alleged effect. Nor can it be said that, generally, better dimensional precision is achieved by integrally forming a curved surface in a tool body than by providing said curved surface as a separate part. Therefore, in the absence of any recognizable further technical effect, the distinguishing feature can only be regarded as an alternative construction of the anti-rotation surface.

The skilled person faced with the technical problem of finding an alternative construction to the press-fitted pin of D1 would obviously consider forming the pin as an integral part of the insert-receiving pocket. Indeed the design alternative of forming a pin element as an integral part of a base surface is known to the skilled person from common general knowledge and this also finds specific application in the present technical field, as shown by D3. In Fig. 3 of D3 the pin 13, which forms the anti-rotation surface of the tool body for engaging a stop surface 19 of the insert, is represented as an integral part of the tool body 10.

Therefore, the skilled person would arrive at the subject-matter of claim 1 without exercising any inventive skill.

5.4 As a consequence, auxiliary request III is not allowable due to lack of inventive step (Article 56 EPC).

6. Auxiliary request IV

The claims according to auxiliary request IV were filed during the oral proceedings, after the discussion of the main request and auxiliary requests I to III. The appellant's submission that auxiliary request IV was filed in response to the Board's view that the claims of the patent in suit referred to the contact which occurred in practice does not justify the late filing, because this view was already set out in the communication accompanying the summons to oral proceedings and, therefore, the amendment could have been filed in advance of the oral proceedings.

Claim 1 of auxiliary request IV includes all the features of granted claim 1 and, additionally, the feature according to which the engagement between the stop surfaces and the anti-rotation surfaces is such that it results in "broad line or lenticular contact". The introduction of this feature, which is taken from the description of the patent in suit, is prima facie objectionable under Article 84 EPC in view of the presence of the vague terms "broad" and "lenticular".

Accordingly, since auxiliary request IV is considered late-filed and claim 1 is not clearly allowable, this request is rejected as inadmissible (see e.g. T 92/93, Reasons, point B.1).

7. Auxiliary request V

7.1 Claim 1 of auxiliary request V includes all the features of granted claim 1 and, additionally, the features of granted claim 9 according to which "said anti-rotation mounting mechanism comprises at least two anti-rotation surfaces spaced apart in said insert-receiving pocket for engaging two different stop surfaces of said insert".

The arrangement of D1 undisputedly comprises one pin and therefore, a single anti-rotation surface.

Thus, the added features confer novelty to the subject-matter of claim 1 with respect to the arrangement in D1.

7.2 The distinguishing features have the effect of reducing the forces between the anti-rotation surface in the insert-receiving pocket and its corresponding stop surface in the insert, and therefore solve the problem of improving the insert's resistance to rotation.

The skilled person faced with the problem of improving the insert's resistance to rotation in the arrangement of D1 would look for a more effective manner of securing the insert in the insert-receiving pocket. The insert of D1 is provided with a plurality of recesses, i.e. of stop surfaces, around its circumference. D4 already discloses effectively preventing rotation of an insert by means of two surface portions (13b) of the insert abutting corresponding walls (37) in the insert-receiving pocket (a lower portion 37 is shown in Fig. 3; the presence of two such portions is clearly derivable from the right-hand portion of Fig. 6 which shows an insert-receiving pocket without the insert, and from the disclosure on page 6, line 3, that "at least one shoulder 33 has a lower portion 37). In other words, D4 discloses actively using more than one of the stop surfaces provided in the insert for preventing its rotation. Therefore, the skilled person would recognise that a manner of solving the above-mentioned technical problem is to actively use more than one of the recesses provided in the insert of D1. This requires the provision of at least a second pin in the arrangement of D1 such that the first and second pins engage two recesses of the insert, a modification that does not present any difficulty for the skilled person. In doing this, the skilled person would arrive at the subject-matter of claim 1 without exercising any inventive skill.

7.3 As a consequence, auxiliary request V is not allowable due to lack of inventive step (Article 56 EPC).

8. Auxiliary request VI

8.1 Claim 1 of auxiliary request VI includes all the features of granted claim 1 and, additionally, a feature taken from the description of the patent in suit (see par. [0014]), according to which "a line drawn tangent to portions of engagement between said stop surface and said anti-rotation surface traversing the outer circumference of the insert at an angle which is non-orthogonal to the outer circumference of the insert".

8.2 The questions of whether this amendment meets the requirements of Article 123(2) or 84 EPC can be left aside, because it is immediately evident that the added feature does not establish novelty over D1. As explained by the Board during the oral proceedings, since the recesses of the circular insert of D1 are defined by portions of circles which centres lie outside the outer circumference of the insert, any line drawn tangent to a recess, i.e. to a stop surface, traverses the outer circumference of the insert at an angle which is non-orthogonal to the outer circumference of the insert.

8.3 Therefore, auxiliary request VI is not allowable due to lack of novelty (Article 54(2) EPC).

9. Auxiliary request VII

9.1 Independent claims 1 and 9 of auxiliary request VII combine the features of claims 1 and 6 and claims 10 and 14 respectively of the patent as granted, and find their basis in claims 1, 2 and 7 and claims 11, 12 and 16 respectively of the application as filed.

Dependent claims 2 to 8 and 10 to 13 correspond to granted claims 2 to 5, 7 to 9, 11, 13, 15 and 16, respectively.

The description is amended to be in conformity with the new claims, and to acknowledge the prior art according to D1. Furthermore, the expression "few thousandths of an inch (mm)" in col. 5 is replaced by "few thousandths of an inch (1 inch equals 25.4 millimeters)" to overcome an objection under Article 123(2) EPC (under Article 100(c) in the notice of opposition) raised by the appellant. The Figures are the same as those of the patent as granted.

Accordingly, the amendments do not give rise to objections under Article 123(2) and (3) EPC.

9.2 The appellant submitted that the feature of claims 1 and 9 according to which "said side surface of said insert includes a sinusoidal profile that defines said stop surfaces" was not clear and not supported by the description.

It is a fact that the wording of claims 1 and 9 was already present as such in the granted claims, and that case law exists (see e.g. T 367/96) according to which objections based upon Article 84 EPC against a claim resulting in substance from the combination of claims of the patent as granted should not be allowed. In the present case, however, the question of whether an objection under Article 84 is admissible against claims 1 and 9, which forms the basis for the appellant's request of referring a question to the Enlarged Board of Appeal, can be left aside, because it is readily apparent that the appellant's objections are unfounded. In fact, giving the term "profile" its ordinary meaning (i.e. outline or contour), it is clear that the above-mentioned feature can only refer to the sinusoidal curve that forms the boundary or edge of the stop surface on the side surface of the insert. This reading is fully supported by the description, which discloses (see col. 5, lines 3 to 8) that the side edges of the stop surfaces create a continuous sinusoidal curve around the circumference of the sidewall of the insert (see also Fig. 3).

It follows from the above that, for the purposes of the present decision, there is no necessity to refer the appellant's question to the Enlarged Board of Appeal in application of Article 112(1)(a) EPC.

9.3 In the insert according to D1 (see D1f), the profile of the stop surfaces in the side surface of the insert is essentially defined by straight lines. Therefore, D1 does not disclose the feature of claims 1 and 9 according to which the side surface of said insert includes a sinusoidal profile that defines said stop surfaces. Since this feature is not disclosed by the other available prior art documents either, the subject-matter of the independent claims is novel.

9.4 Compared to the arrangement of D1, which is the closest prior art for both the mechanism of claim 1 and that of claim 9, the distinguishing features provide a smooth continuous profile in which there are no sharp transitions which could concentrate stresses in use and thus possibly generate cracks in the insert.

Therefore, the problem solved can be regarded as improving the insert's resistance to cracks.

Although it is generally known that stresses might concentrate where sharp transitions are present, there is no indication in the available prior art which would lead the skilled person to consider that the sharp transitions in the profile of the recesses (i.e. the stop surfaces) play a significant role in the generation of cracks in the insert, and therefore, that precisely those sharp transitions should be removed. In any event, even if the skilled person would consider removing the sharp transitions, there is no indication suggesting doing this by modifying the straight lines in the profile so as to provide a sinusoid. In fact, the skilled person, having regard to his general knowledge, would rather consider simply replacing the sharp transitions with curved portions. Therefore, the subject-matter of independent claims 1 and 9 is not suggested by the available prior art. It thus involves an inventive step (Articles 52(1), 56 EPC).

9.5 It follows that claims 1 and 9, together with dependent claims 2 to 8 and 10 to 13, the amended description filed at the oral proceedings, and the drawings as granted, form a suitable basis for maintenance of the patent in amended form.