Newworld built in gas oven turn gas off and on

[kr5ai]

I have the following gas build in oven;

Newworld vision model 200502074

The problem I am having is the ovens flame turns off and on and off after every few minutes. The oven dispaly and light is on the whole time, then when I put the oven on it will light up fine and start heating up. After a few minutes the flame will go off, and the ingnition will keep clicking automatically for a few minuters until the flame comes back on (hence I think this particular model has a sparking ignition system). Then the whole process will start over again, I carnt smell any excess gas. Please please can you help.

parts for this model can be seen at

http://www.espares.co.uk/parts/cookers-and-hobs/new-world/200502074/p/1092/327/0/884950


thanks kris