A proportion-integration-derivation (PID) kettle structure includes: a kettle upper cover; a water filling cap, embedded into kettle upper cover; and a PID element, fixed onto inner side of water filling cap, to indicate usage time of a filter core in a kettle. The PID element includes: a guiding axis, disposed at an end inside the water filling cap; a pushing rack, sleeved around the guiding axis; a reset spring, disposed between pushing rack and guiding axis; an arc-shape rack pushing boss, disposed symmetrically on both sides of the pushing rack, used to push the pushing rack to move, when water filling cap is opened or closed; a driving gear, disposed at front end of the pushing rack, to act in cooperation with the pushing rack; and a driven gear, disposed below the driving gear, and connected to rotate along with the driving gear.

A proportion-integration-derivation (PID) kettle structure includes: a kettle upper cover; a water filling cap, embedded into kettle upper cover; and a PID element, fixed onto inner side of water filling cap, to indicate usage time of a filter core in a kettle. The PID element includes: a guiding axis, disposed at an end inside the water filling cap; a pushing rack, sleeved around the guiding axis; a reset spring, disposed between pushing rack and guiding axis; an arc-shape rack pushing boss, disposed symmetrically on both sides of the pushing rack, used to push the pushing rack to move, when water filling cap is opened or closed; a driving gear, disposed at front end of the pushing rack, to act in cooperation with the pushing rack; and a driven gear, disposed below the driving gear, and connected to rotate along with the driving gear.

An appliance including: a vessel having a chamber for containing flowable substance; a first sensor arrangement measuring a parameter indicative of the amount of flowable substance in the chamber; wherein, the appliance is configured to determine a target angular deviation from a reference axis required to pour a predetermined amount of flowable substance from the chamber

An appliance including: a vessel having a chamber for containing flowable substance; a first sensor arrangement measuring a parameter indicative of the amount of flowable substance in the chamber; wherein, the appliance is configured to determine a target angular deviation from a reference axis required to pour a predetermined amount of flowable substance from the chamber