Thursday, February 28, 2019 EQE Paper B 2019 - Cooking with solar radiation

EQE Paper B of 2019 concerned cooking using concentrated solar radiation. Candidates needed to evaluate carefully amendments suggested by the client, to see if they were novel/inventive and supported by the application. 

The claims as filed and as amended by the client had several problems for which the candidates had to find solutions. The comments below are not a full response to the office action, but give an indication of the problems that had to be solved. 

Claim 1 in the application as filed is not novel over D1. The client has suggested to add that the storage unit contains a salt composition, but this claim seems to be not inventive over the combination of D1 and D2. Putting the pot of D2 on the cooker of D1 seems an obvious combination, and would fall under this suggested claim. So more is needed. Fortunately, the client already remarks that it is the melting of the salt that is important. Since melting of salt does not occur in the combination of D1 and D2, this further addition seems to solve the problems. The addition is supported by section [0009]. 

New claim 1 is novel over D3 since D3 does not disclose cooking food.

The closest prior art for claim 1 is D1 since it is the only document that discloses a process for cooking with solar radiation. 

Claim 2 in the application as filed is not novel over D2 and D3. Furthermore, the Examiner objected to a lack of essential features. The client's amendments do not complete solve these problems. Adding that there is an empty space is not enough; D2 also has empty space in the form of gaps between the salt. The application adds that the empty space should be dimensioned to allow the salt to expand upon melting. This is supported by sections [010] and [013].

The other amendment in claim 2 is needed to make the claim novel over D3. However, the range is not supported by the application, since the end point 120 is not disclosed. Instead of the point 120, the point 130 is disclosed. Accordingly, a better range is to use 130-350. This will be sufficient for the goals of the client according to his letter.

One could wonder if it is allowed under A.123(2) to restrict a range on the basis of an isolated value given as an example. The guidelines do not give this particular example, but in part H-IV, 2.4 a somewhat similar example is given with two ranges instead of with a range and an isolated value. The case law book does give this particular scenario, in II-E, 1.3.2. The case law cited there, e.g., T201/83 require an additional test, namely that the  'this value was not so closely associated with the other features of the example as to determine the effect of that embodiment of the invention as a whole'. Here that is not the case. We conclude that restricting the range to 130-350 does not constitute added subject matter. 

Conceivably, one could disclaim the salt 'magnesium chloride hexahydrate' instead of adding a range to claim 2. This would be allowed under G 2/10 since it disclaims a disclosed embodiment. This seems to run counter the wishes of the client though. 

The closest prior art for new claim 2 seems to be D2. Only document D1 and D2 are related to cooking, but the latter has more features in common. 

Claim 4 and 5 were switched around by the client. This switch appears to be supported by the application as filed. The embodiment of figure 3 of the application has handles with which unit 3 can be transported, an so it is portable.

The claims for our solution for paper B 2019 are as follows: 

1. A cooking process including the steps:
providing a heat storage unit (3) containing a salt composition (6);
concentrating solar radiation (12) onto the heat storage unit (3) to heat it and to melt the salt composition; and
cooking food (8) placed on the heat storage unit (3).

2. A heat storage unit (3) for use in the process of claim 1, characterised bycomprising:
a box (4) having heat-insulating walls and an opening,
the box (4) containing a salt composition (6),
a light-absorbing plate (5) fitted in the opening and in thermal contact with the salt
composition (6), and
a cooking surface (9) in thermal contact with the salt composition (6),
characterized in that:

the box (4) contains an empty space (7) dimensioned to allow the salt composition to expand upon melting, and in that
the salt composition (6) has a melting temperature from 130C to 350C.

3. Heat storage unit according to claim 2, wherein the cooking surface (9) is a surface of a cooking plate (2) fitted in a second opening of the box (4) and in thermal contact with the salt composition (6).

45. Heat storage unit according to claim 2, wherein the cooking surface (9) is a surface of the light-absorbing plate (5).

54. Heat storage unit according to any of claims 2 or to 34, wherein the heat storage unit (3) is portable by means of handles (10).

6. A solar cooker (1) comprising:
a heat storage unit (3) according to any of claims 2 to 5;
a parabolic mirror (11) for concentrating solar radiation (12) on the light-absorbing plate (5) of the heat storage unit (3).