Abstract: A shutter assembly for an animal-watering valve which is operable by a small animal moving a lever arm from side to side. The primary purpose of the shutter is to prevent the animal from stuffing material between the lever arm and the water passage and thereby render the valve inoperable i.e. in a full on, full off or leaking mode. The shutter includes a disc mounted on the lever arm which substantially covers the annular opening between the lever arm and the water passage formed in the valve housing. To insure operablility of the valve at elevated water pressures, a pressure equalization chamber may be formed in the valve to equalize the water pressure on the shutter when the valve is in the closed position.

Abstract: A miniature valve for very small animals such as tiny weanling mice consisting briefly of a housing having an interior passage. A lever arm extends through the passage and slightly beyond the end of the housing so that the animal can move the lever by biting it with its teeth or deflecting it with its tongue. Deflection of the valve arm causes a valve head member to pivot and partially lift off a valve seat. The valve seat is of resilient material and formed at an angle to the underside of the valve head so that a "line-point" type contact is made between the valve head member and the valve seat. A biasing member, such as a spring, returns the lever arm to a centered position when the animal lets go of the lever thereby automatically preventing further water flow.