A problem with toasters is that during the first toasting, the present dust particles are burnt and introduces off flavors into the bread. A solution to this is to provide a plastic lid. However, if the lid is closed while the toasters is still hot, the lid can be deformed or melted. A Shape Memory Spring has been built to prevent such a mishap. When the Shape Memory Spring reaches a critical temperature of 60°C, the Shape Memory Spring induces a latch mechanism that makes it impossible to close the lid. Closing of the lid is only possible after the Shape Memory Spring has cooled down to room temperature.