T 0910/94 26-01-2000

1. The appeal is admissible.

2. Main request

2.1. Claim 1 according to this request differs from claim 1 as granted amongst others in that it is directed to a yarn winder comprising a plurality of yarn take-up means, wherein the bobbin holding portion of each of the take-up means is more than 800 mm in length (see feature c-2).

2.2. In the originally filed documents take-up means having a length of more than 800 mm in length were solely disclosed in connection with the description of the preferred embodiment, in particular as a first aspect of the invention (see page 9, lines 9 to 14). In accordance with this first aspect of the invention, field-balancing of the bobbin holding portion of such a long yarn take-up means requires the provision of at least three groups of holes for the attachment of weights, said holes being arranged in balance correcting planes located at opposite ends of the bobbin holding portion and at least one intermediate position, and said holes having the same phase arrangement in the respective balance correcting planes (see page 10, lines 2 to 12 of the originally filed description).

2.3. It is apparent from this information that for carrying out the field balancing technique, in addition to the position of the three planes, the phase-position of the holes for the attachment of the balancing weights must also be known. Namely, in contrast to the balancing techniques in which weights can be attached at any wanted phase position, the weights in accordance with the yarn winder claimed can only be attached to the holes and therefore the phase position of the holes must be known for calculation of a weight distribution of the balancing weights with respect to the phase of the holes.

In so far the description of the preferred embodiment includes all the essential parameters for carrying out field-balancing by reference to the holes for the attachment of weights being arranged in particular balance correcting planes and that the holes have the same phase arrangement in each plane. While it is further stated that the number of the holes, the type of the holes and the arrangement of the holes with respect to each other may vary (see page 10, lines 14 to 18), no exception is mentioned for the phase arrangement of the holes.

2.4. Although the respondent argued during the oral proceedings that limitation of the subject-matter of claim 1 to include the phase angle of the holes was not required because the skilled person would be able to calculate the weight distribution by other means, no evidence or arguments were provided as to how such calculation should be carried out without information concerning the phase positions of the holes.

Therefore in the absence of reasons why the balancing parameter concerning the phase arrangement of the holes should be considered redundant, and the fact that the subject-matter now claimed is disclosed as a combination of features including the phase arrangement of the holes, the Board is of the opinion that only the combination can be seen to be supported by the originally filed application documents.

2.5. The respondent's argument according to which the decision T 301/87 setting limits on the introduction of an objection under Article 84 EPC applied in the present case, is based on the assumption that this objection is merely related to the arrangement of holes as such.

However, claim 1 was amended such that it now relates to a preferred embodiment having a particular combination of features, which in accordance with the disclosure of the patent not only requires a particular arrangement of the holes, but also a known phase arrangement for the holes in all balancing correcting planes, so as to be able to calculate the weight distribution of the balancing weights during field-balancing.

Therefore, in the present case the amendment concerning the long spindle caused Article 84 EPC to be contravened, and it cannot be concluded from decision T 301/87 that this contravention is not to be considered.

2.6. Since claim 1 of the main request does not include the feature according to which the holes have a known phase arrangement, it does not meet the requirements of Article 84 EPC in respect of essential features of the invention now claimed.

Therefore, the main request is not allowable.

3. First subsidiary request

3.1. Amendments

3.1.1. Features (a) to (b-4) of claim 1, as well as its feature (c-5) and that part of (c-4) according to which the bobbin holding portion may be dynamically balanced by field balancing, correspond to the features of the originally filed claim 1. Feature (b-5) was comprised in originally filed claim 4 and the combination of the characterising features (c-1) to (c-5) was described with respect to the first aspect of the invention on pages 9 to 17 of the originally filed description in connection with figures 1 and 2 of the originally filed drawings.

Moreover, claim 1 according to the first auxiliary request includes all features of claim 1 of the patent specification and is restricted over this claim by features (b-5), (c-1), (c-2) and the features of (c-3) and (c-4) according to which the holes have the same phase arrangement in the respective planes and field-balancing is used for reducing vibrations generated by the spindle.

Dependent claims 3 to 10 correspond to originally filed claims 5, 7, 9, 11 to 14 and 6 and the features of claim 2 are disclosed in the originally filed description on page 9, line 28 to page 10, line 12.

The description has merely been amended in order to adapt it to the claims of the first subsidiary request and to correct some clerical errors.

Therefore, the first subsidiary request does not contain subject-matter which extends beyond the content of the application as filed and the claims are not amended in such a way as to extend the protection conferred.

3.1.2. Compared to claim 1 according to the main request, claim 1 according to the first subsidiary request comprises all essential features for balancing a bobbin holding portion longer than 800 mm by field-balancing. Additionally, also claim 2 has been amended in order to clarify that the holes in the disc have the same phase arrangement as the holes in the other balance correcting planes.

Therefore, the objection under Article 84 EPC raised against claim 1 of the main request is no longer relevant for claim 1 according to the first auxiliary request.

3.1.3. In view of the above assessment, the amended documents according to the first subsidiary request do not give raise to objections under Articles 123(2), (3) and 84 EPC.

3.2. Novelty

3.2.1. The most relevant state of the art is disclosed in D1 (EP-A-0 167 708 only, because US-A-4 575 015 is no prior art). This document undisputedly shows a yarn winder as described in the preamble of claim 1.

3.2.2. The appellant's argument that D1 additionally discloses a revolver winder as described in feature (c-1) of the characterising portion of claim 1, is based on the assumption that this feature is implicit in D1.

However, D1 essentially refers to a spindle and is silent about the kind of yarn winder for which this spindle may be used. The only information given in D1 which implicitly discloses the combination of such a spindle and a yarn winder is the disclosure on page 1, lines 8 and 9, according to which the claimed bobbin holder is useful for coiling and feeding thread.

Documents D7 to D10 and D15 to D17 cited by the appellant show that the use of a revolver mechanism in a yarn winder is well known. However, that does not mean that a winder comprising a revolver mechanism is implicitly disclosed in D1, because the combination of the spindle according to D1 with a revolver winder requires at least a selection of such a particular winder.

Therefore, in contradiction to the appellant's opinion, feature (c-1) is not disclosed in D1.

3.2.3. Furthermore, it is undisputed that D1 neither refers to a bobbin holding portion of more than 800 mm in length, nor to a balancing method for this element as defined in features (c-2) to (c-5) of the characterising portion of claim 1.

All further documents cited in the appeal proceedings are less relevant than D1. Novelty of the subject-matter of claim 1 is therefore established.

3.3. Inventive step

3.3.1. On the basis of a yarn winder according to D1, the problem to be solved may be regarded as to improve the productivity of such a known yarn winder (see patent specification, page 2, lines 21 to 26).

This problem is solved by the provision of a plurality of yarn take-up means provided on a rotatable base and the selection of bobbin holding portions of more than 800 mm in length (features c-1 and c-2) as well as measures to make them suitable for high speed operation.

Since yarn take-up means having long bobbin holding portions tend to vibrate when they are rotating (see patent specification, page 2, lines 30, 31), high speed operation requires measures to reduce the vibrations caused by the yarn take-up means.

As to the latter aspect, the yarn winder defined in claim 1 includes at least three groups of holes, each group of holes being arranged in balance correcting planes located at opposite ends of the bobbin holding portion and at least one intermediate position, and each group of holes having the same phase arrangement in the respective plane, the holes being adapted for the attachment of weights, by means of which the bobbin holding portion may be dynamically balanced by field-balancing for reducing vibrations generated by the spindle (features c-3 to c-5).

3.3.2. Starting from D1, it requires a plurality of selections to arrive at the yarn winder as defined in claim 1. In particular the winder type has to be selected, the length of the spindles, a balancing method for the spindles, an arrangement for balancing weights, and means for attaching the balancing weights to the spindles.

The revolver winder selected according to feature (c-1) of claim 1 is well known, as for example shown by documents D7 to D10 and D15 to D17.

D16 additionally describes the use of bobbin holding portions of more than 800 mm in such a revolver winder according to feature (c-2).

With respect to the selection of a balancing method according to features (c-3) to (c-5), D2A teaches (see particularly, paragraph 4.6) that

- balancing weights have to be fixed at the periphery of the rotor in discrete balancing planes,

- the amount of balance correcting planes has to be selected amongst others in dependence of the type of the rotor (rigid or flexible) and on its operating speed,

- the balance correcting planes have to be positioned in dependence of the particular rotor (for example in the case of three planes at the opposite ends and an intermediate position of the rotor).

Furthermore, D4 shows that a rotor may be balanced by field-balancing.

Therefore, the features (c-1), (c-2), (c-4) and (c-5) are well known in the art and could be selected by the skilled person for a yarn winder according to D1.

3.3.3. However, no reason is apparent why the skilled person would select precisely this combination of features to solve the productivity problem mentioned above.

Although it is generally accepted that revolver winders having long spindles may lead to high productivity, there is no suggestion given in the available documents which would lead the skilled person to consider the spindle arrangement of D1, revolver winders having long spindles and the selection of measures making the winder particularly suitable for field- balancing, in combination.

The skilled person could select other methods for reducing the vibrations, as for example constructional measures or damping means, or simply select some other balancing method than field-balancing.

Hence, the plurality of selections according to claim 1 is not determined by a one-way situation, and their combination is not regarded as obvious.

3.3.4. Furthermore, as it was admitted by the appellant, there is no suggestion in the available prior art to provide groups of holes in discrete balance correcting planes of a rotor, which holes have the same phase arrangement in each plane and are adapted for the attachment of weights, in order to enable and facilitate field-balancing of the rotor.

Therefore, the skilled person had at least no suggestion for the particular arrangement of the holes as defined in feature (c-3).

4. The Board therefore comes to the conclusion that the subject-matter of claim 1 according to the respondent's first subsidiary request cannot be derived in an obvious manner from the cited prior art and accordingly involves an inventive step (Article 56 EPC). This claim together with its dependent claims 2 to 10 and the amended description and drawings therefore form a suitable basis for maintenance of the patent in amended form.

5. Second subsidiary request

As the respondent's first subsidiary request is considered allowable, there is no need to consider the second subsidiary request.