Abstract: A nursing bottle air-inlet regulating valve comprising a flat elastomeric valve (1) that lies on the inner part of a threaded base (2) of a nursing bottle body (3) and comprises small domes (4) on fee upper side (where the liquid is). The domes (4) have a slit (5), through which air flows to balance the pressure in the nursing bottle. Vent channels (8) are included on the Underside of the membrane, which is the side the membrane contacts the threaded base (2) of the nursing bottle. The membrane (1) has a perimeter wall or edge (9) that fits in the inner perimeter of the threaded base (2), continuing in a hollow perimeter channel (7) allowing air to circulate when the base (2) is unthreaded. The domes (4) are connected to the perimeter channel by the vent channels (8). Air-inlet flow is regulated by how much the vent channels (8) are squashed.

Abstract: Nursing bottle air-inlet regulating valve comprising a flat elastomeric valve (1) that lies on the inner part of the threaded base (2) of the nursing bottle body (3) and comprises small domes (4) on the upper side (where the liquid is). Said domes (4) have a slit (5) at the end, through which the air flows to balance the pressure in the nursing bottle. Furthermore, comprises vent channels (6) on the underside (facing the domes, where there is no liquid), which is the side the membrane contacts the threaded base (2) of the nursing bottle. The circular membrane (1) comprises a perimeter wall or edge (9) that fits in the inner perimeter of the threaded base (2), continuing in a hollow perimeter channel (7) allowing air to circulate when the base (2) is unthreaded. The domes (4) are connected to the perimeter channel (7) by small bridges (8) that complete the air-inlet flow, which will be regulated by how much the vent channels (6) are squashed, which are also connected to the hollow perimeter channel (7).

Abstract: A drinking vessel with a cup having a hollow inner body and an open end, a removable cap for sealingly closing the open end, an outer surface with a spout and an air vent, and an inner surface with a tubular outlet passage and a tubular inlet passage. The cup further contains a one piece flow control valve made of an elastomeric material. The flow control valve contains an inlet valve and an outlet valve joined together by a connector bar. The outlet valve of parabolic configuration has a reinforcing ring and a partition wall, held in place by two jutting out walls that are part of the connector bar. The inlet valve has a tubular edge sitting on two wing-like projections holding a membrane with a slit. The tubular edge is integral with the connector bar and the two wing-like projections, with outlet and inlet valves fitting into the outlet and inlet passages, respectively.