A sanitary insert part includes an insert housing, which includes in a housing interior thereof a functional element that controls throughflow and that has at least one throughflow orifice. At least one throughflow opening is delimited by a peripheral wall, the shape of which can be changed against a restoring force as a result of the pressure of the inflowing water in such a manner that the at least one throughflow orifice has a variable orifice cross section which can be changed, in dependence on the pressure of the inflowing water, between an open position and a minimized position having a reduced orifice cross section by comparison.

A regulating device may include a housing that defines an inlet chamber and an outlet chamber, with a flow restriction seat between the inlet chamber and the outlet chamber. A flow restriction valve is movable relative to the flow restriction seat to adjust the flow between the inlet chamber and the outlet chamber of the regulating device. A servo valve having a servo chamber may be used to adjust the position of the flow restriction valve. The servo chamber may be fluidly coupled to the inlet chamber though a fixed flow restriction and to the outlet chamber though an adjustable flow restriction. A stepper motor may be used to adjust the servo valve to adjust the adjustable flow restriction between the servo chamber and the outlet chamber. This causes a change of the servo pressure, which moves the flow restriction valve and adjusts the flow of the regulating device.

The invention relates to a sanitary insert part (1) having an insert housing (2), which (2) includes in a housing interior thereof a functional element (3) that controls throughflow and that has at least one throughflow orifice (4). The insert part according to the invention is characterized in that at least one throughflow opening (4) is delimited by a peripheral wall, the shape of which can be changed against a restoring force as a result of the pressure of the inflowing water in such a manner that the at least one throughflow orifice (4) has a variable orifice cross section which can be changed, in dependence on the pressure of the inflowing water, between an open position and a minimized position having a reduced orifice cross section by comparison.