T 0399/20 02-06-2023

Summary of Facts and Submissions

I. With the decision posted on 18 December 2019, the opposition division decided that the patent and the invention to which it related according to the second auxiliary request met the requirements of the EPC.

II. The opponent filed an appeal against this decision.

III. Oral proceedings were held before the Board on 2 June 2023. As announced with the letter dated 19 April 2023, the respondents (patent proprietors) did not attend the oral proceedings. In accordance with Rule 115(2) EPC and Article 15(3) RPBA 2020 the proceedings were continued in their absence and they were treated as relying on their written submissions.

IV. The appellant (opponent) requested that the decision under appeal be set aside and that the patent be revoked.

V. The respondents requested that the appeal be dismissed, or in the alternative, that the patent be maintained according to one of auxiliary requests 1 - 5 filed with the reply to the appeal on 16 September 2020.

VI. The independent product claims read as follows:

Main request (as found allowable by the opposition division):

"A carrier (12f) and mount (24f) assembly for a heavy vehicle disc brake, the assembly comprising:

a carrier (12f) having a first location formation (32f) formed therein,

a mount (24f) having a second location formation (30f) formed therein, wherein the second location formation (30f) is aligned with the first location formation (32f), and wherein the carrier (12f) is mounted to the mount (24f) via two or more fasteners that extend in a direction substantially parallel to a tangential direction (T) of insertion or removal of a friction element into or from the carrier (12f); and

a locator (38f) positioned in the first (32f) and second (30f) location formations to enable the carrier (12f) and mount (30f) to be assembled in the correct position, and wherein the locator (38f) is a bush, and the bush extends at least partially through the first (32f) and second (30f) formations, characterised in that the locator (38f) is an interference fit to the first (32f) and second (30f) location formations."

Auxiliary request 1

The characterising part has been changed (additions underlined, deletions struck through) as follows:

"the locator (38f) is at least a close [deleted: interference] fit to the first (32f) and second (30f) location formations; and wherein the bush is a split bush."

Auxiliary request 2

The following feature is added to claim 1 of the main request:

"wherein the bush is a split bush."

Auxiliary request 3

The following feature is added to the independent claims of auxiliary request 1:

"wherein an end of the bush received in the mount (24f) has a chamfered outer edge (70f)."

Auxiliary request 4

The extra features of auxiliary requests 2 and 3 are added to the independent claims of auxiliary request 1.

Auxiliary request 5

The following features replace the characterising part of the independent claim 1 as granted:

"the carrier comprises two holes (84f,86f) arranged such that one hole is positioned on either side of a plane defined by an axis extending substantially parallel to a direction of insertion or removal of a friction element into or from the carrier (12f) and an axis of rotation of a rotor of a disc brake, and wherein the mount (24f) comprises two holes (76f,78f) positioned to be substantially coaxial with the two holes of the carrier (12f), and wherein one of the two or more fasteners extends through each of the holes for mounting the carrier (12f) to the mount (24f);

the first location formation (32f) is integrally formed with one of the holes (74f) in the carrier (12f) and the second location formation is integrally formed with one of the holes (72f) in the mount (24f);

further comprising a further bush (68f) positioned to extend at least partially through the other of the two holes (72f) formed in the carrier (12f) and mount (24f) and

characterised in that the locator (38f) is at least a close fit to the first (32f) and second (30f) location formations and in that the further bush (68f) is a loose fit to the bush (72f) in the mount (24f)."

VII. Documents

The following document is relevant for this decision:

E1: US 2008/0135352 A1

VIII. The appellant argued essentially the following:

a) Main request - inventive step

The subject-matter of claim 1 lacked an inventive step over E1 as the closest prior art.

b) Auxiliary requests 1, 3, 4 and 5 - Reformatio in peius

In the claims as found allowable by the opposition division, it was specified that the locator was at least an interference fit to the first and second location formations. Auxiliary requests 1, 3, 4 and 5 have changed this to a "close fit". A close fit, as defined by the patent at p. 3, l. 7, was broader than an interference fit because it included the possibility of being a transition fit. Thus the amended claims included embodiments which were broader than those found allowable by the opposition division and, hence, offended against the prohibition of reformatio in peius. These requests were therefore not admissible.

b) Auxiliary request 2 - inventive step

The subject-matter of claim 1 did not involve an inventive step because a split bush was a well known connection means.

IX. The respondents argued essentially the following:

a) Main request - inventive step

E1 did not disclose the characterising feature of claim 1 whereby the locator is an interference fit to the first and second location formations. Paragraph [0014], final sentence, taught that an individual joint should not be over-constrained to prevent binding. This led the skilled person away from the claimed invention and, hence, it was not obvious for the skilled person to design the locator with an interference fit.

b) Auxiliary requests 1, 3, 4 and 5 - Reformatio in peius

The respondents stated in the reply to the appeal with regard to auxiliary request 1, paragraph 11.1, that "[t]he Respondents recognise that under Reformatio in Peius principles this auxiliary request is admissible in the unlikely event that the Appellant's attacks at 7 or 7.1 are successful."

The respondents also proposed filing new requests replacing "close fit" with "interference fit" during the oral proceedings.

b) Auxiliary request 2 - inventive step

There was no suggestion that a split bush was used in E1, in particular references to pins and dowels in E1 did not suggest a particular type of bush that was resiliently compressible. This had the advantage of ensuring accurate alignment due to the interference fit but nevertheless enabled assembly to be more easily achieved.

The subject-matter of claim 1 therefore involved an inventive step.