Since the cover of the insulated jar uses a third class lever, the distance moved by the effort is furthest. Sometimes, when the cover is not opened completely, it will fall back to its original closed position. The grip where the effort is applied might spoil due to the impact of the fall. Hence, loud distracting sound is produced.
We can support the cover by linkages, as seen in the 3th image. With the help of the movable pivot, the cover will open, fold to the side and close easily, without the risk of it falling and spoiling the grip.
By adding a hinge there, the cover will be prevented from falling. It will stay in the open position until the user closes it. This prevents the risk of it falling and damaging the grip.