Animal drinking troughs have pressure reducers for reducing the higher pressure of the liquid supply to a low liquid pressure for supplying the animal drinking troughs. For various reasons, it is desired to change the reduced pressure. This takes place by adjustment of the pressure reducers. It is known to undertake such an adjustment with compressed air. This requires a separate compressed air source and a corresponding pipe system. The invention makes provision to adjust the pressure reducer hydraulically by means of the higher pressure of the liquid of the liquid supply. The energy required for adjusting the pressure reducers thereby provides the liquid pressure of the liquid supply. As a result, the pressure reducers according to the invention operate autonomously. A separate energy source for adjusting the pressure reducers is not required.

Animal drinking troughs have pressure reducers for reducing the higher pressure of the liquid supply to a low liquid pressure for supplying the animal drinking troughs. For various reasons, it is desired to change the reduced pressure. This takes place by adjustment of the pressure reducers. It is known to undertake such an adjustment with compressed air. This requires a separate compressed air source and a corresponding pipe system. The invention makes provision to adjust the pressure reducer hydraulically by means of the higher pressure of the liquid of the liquid supply. The energy required for adjusting the pressure reducers thereby provides the liquid pressure of the liquid supply. As a result, the pressure reducers according to the invention operate autonomously. A separate energy source for adjusting the pressure reducers is not required.

A pressure regulator has a pressure chamber connected to an inlet flow area which receives liquid flow. As liquid flows into a forward chamber of the pressure chamber, pressure is exerted on the forward face of the piston, which in turn causes the piston to slide longitudinally through the pressure chamber. An internal passageway through the piston fluidically connects the forward pressure chamber and rear pressure chamber such that as the piston slides into the rear pressure chamber pressure increases at the rear pressure chamber, which in turn forces the piston to move forwardly, thus regulating flow out of the pressure chamber. A hand wheel is configured to turn a movable plate located inside the pressure chamber, with the movable plate configured to impede the piston from moving rearwardly. Pressure sensors and vents with a pressurized air source may be used to keep the pressure within a desired range.

The valve includes a casing arrangeable so the fluid in the passage flows over an outer side. The valve includes a piston axially slidably positionable within the casing, and the axial position regulates the fluid pressure in the poppet valve passage downstream, an annular clearance between the piston and casing. The valve includes a dynamic seal between the piston and casing to seal the annular clearance end. The valve includes a piston chamber located on the dynamic seal opposing side of the annular clearance so a leakage flow may cross the dynamic seal between the annular clearance and piston chamber. The fluid pressure in the piston chamber varies the axial position within the casing. A diversion path formed in the casing diverts fluid for the leakage flow into the annular clearance from the fluid flow in the passage, the diversion path having filter to filter debris from the diverted fluid.

The valve includes a casing arrangeable so the fluid in the passage flows over an outer side. The valve includes a piston axially slidably positionable within the casing, and the axial position regulates the fluid pressure in the poppet valve passage downstream, an annular clearance between the piston and casing. The valve includes a dynamic seal between the piston and casing to seal the annular clearance end. The valve includes a piston chamber located on the dynamic seal opposing side of the annular clearance so a leakage flow may cross the dynamic seal between the annular clearance and piston chamber. The fluid pressure in the piston chamber varies the axial position within the casing. A diversion path formed in the casing diverts fluid for the leakage flow into the annular clearance from the fluid flow in the passage, the diversion path having filter to filter debris from the diverted fluid.

It is proposed to design a fluid flux regulating unit, comprising a first fluid port, a second fluid port and a valve comprising a movable valve part and at least one fluid pressure balancing means, wherein the fluid pressure balancing means comprises a surface in fluid communication with the first fluid port, which has a surface normal vector at least partially in parallel to the moving direction of the movable valve part.