Nipple drinker for poultry waterer with variable flowrate

A nipple drinker 102 for use in a watering system 104 of an animal house having at least one watering pipe 110, wherein the watering pipe carries pressurized water to the nipple drinker, the nipple drinker having a sealing ball 814 that is forced against a sealing bushing 816 thereby forming a watertight seal to prevent leakage of water from the flow channel out through the nipple drinker 102, a bottom pin 818 configured to displace the sealing ball from the sealing bushing to release drinking water through the nipple drinker, a nipple body 806 that receives the sealing ball, the sealing bushing and the bottom pin and forms an internal flow channel from a nipple inlet 808 and past the sealing ball when the sealing ball is displaced from the sealing bushing, and a top pin 812 received by the nipple body and movable in a vertical direction with respect to the nipple body, wherein the nipple body comprises:

• a flow control zone 902 in the internal flow channel, the flow control zone interfacing with the top pin such that vertical movement of the top pin relative the flow control zone provides different flow rates through the nipple drinker such that when the top pin is in a first vertical position there is a first flowrate of water and when the top pin is in a second vertical position, there is a second flowrate of water greater than the first flow rate.