Method for operating a device for the dosed supply of a liquid

A method for operating a device (1) having:

• at least one pump (2) configured to deliver a liquid, the at least one pump (2) having a pump housing (3) having at least one inlet (4) and at least one outlet (5);
• an eccentric (6) arranged on the pump housing (3) so as to be rotatable relative to the pump housing (3);
• and a deformable diaphragm (7) arranged between the eccentric (6) and the pump housing (3), the deformable diaphragm (7) and the pump housing (3) delimiting a delivery path (8) from the at least one inlet (4) to the at least one outlet (5) and forming at least one seal (9) of the delivery path (8), the at least one seal (9) being displaceable along the delivery path (8) by a movement of the eccentric (6) to deliver the liquid, the at least one pump (2) having an electric drive (26) configured to move the eccentric (6), the method comprising:
• detecting a demanded dose amount of the liquid;
• activating the electric drive (26) of the at least one pump (2) to move the at least one seal (9) in a delivery direction (27) from the inlet (4) to the outlet (5) to deliver the liquid by application of an operating voltage (10) to the electric drive (26);
• stopping operation of the at least one pump (2) when the delivered amount of the liquid corresponds to the demanded dose amount;
• stopping movement of the eccentric (6);
• and
• maintaining a holding voltage (35) at the electric drive (26), wherein, in response to the holding voltage (25), a holding torque (38) is exerted on the eccentric (6) and a movement of the eccentric (6) counter to the delivery direction (27) is prevented.