Fuel pump having improved pumping behaviour

The present invention relates to a fuel pump for pumping fuel, comprising a piston (2) and a diaphragm seal element (3), which seals on an inner annular seal seat (4) and an outer annular seal seat (5), wherein the following equation is satisfied: (Ra2-ra2)/(ri+L)2 = ra/ri, where ri is the inner radius of the inner seal seat (4), ra is the inner radius of the outer seal seat (5), Ra is the outer diameter of the piston (2) and L is a difference between an outer radius (Ria) of the inner seal seat (4) and the inner radius (ri) of the inner seal seat (4). The invention further relates to a method for operating a fuel pump. 本发明涉及种用于输送燃料的燃料泵，该燃料泵包括活塞(2)和密封在内环形密封座(4)和外环形密封座(5)上的薄膜密封元件(3)，其中满足下面的公式：(Ra-ra)/(ri+L)＝ra/ri，其中，(ri)是所述内密封座(4)的内半径，其中，(ra)是所述外密封座(5)的内半径，其中，(Ra)是所述活塞(2)的半径，并且其中，(L)是所述内密封座(4)的外半径(Ria)和所述内密封座(4)的内半径(ri)之间的差。本发明还涉及种用于运行燃料泵的方法。