Closure device for a fluid vessel

Abstract

A closure device for a fluid vessel can comprise a bistable valve arrangement which includes first and second valve rim portions and a valve member engageable with either of the rim portions respectively to define an open position in which fluid can exit the vessel and a closed position in which fluid is substantially prevented from exiting the vessel The valve can be arranged to close automatically when an impulse is exerted against the valve member. This can occur for example when the vessel is knocked over and the fluid therein exerts pressure against the valve member.

1 - 63 . (canceled) 
     
     
         64 . A lid for a fluid vessel, comprising:
 a valve that controls flow of fluid from the fluid vessel, and   wherein the valve comprises a plastics material impregnated with a magnetic material.   
     
     
         65 . The lid of  claim 64 , wherein the valve comprises a valve seat, and wherein the valve seat includes the plastics material impregnated with the magnetic material. 
     
     
         66 . The lid of  claim 64 , wherein the valve comprises a valve member that selectively permits and restricts flow through a valve aperture, and wherein the valve member includes the plastics material impregnated with the magnetic material. 
     
     
         67 . The lid of  claim 64 , wherein the valve comprises a valve member that selectively engages first and second valve seats in respective closed and open positions of the valve, and wherein each of the first and second seats includes the plastics material impregnated with the magnetic material. 
     
     
         68 . The lid of  claim 67 , wherein a magnetic attraction between the valve member and the first valve seat is greater than a magnetic attraction between the valve member and the second valve seat. 
     
     
         69 . The lid of  claim 64 , wherein the valve controls flow of the fluid through a valve aperture, and wherein the fluid flows through the valve aperture, irrespective of a rotational orientation of the lid, when the valve is in an open position and the vessel is tilted from an upright position. 
     
     
         70 . A lid for a fluid vessel, comprising:
 a valve that controls flow of fluid from the fluid vessel through a valve aperture, and   wherein the valve aperture is circumscribed by a valve rim portion over which the fluid flows, irrespective of a rotational orientation of the lid, when the valve is in an open position and the vessel is tilted from an upright position.   
     
     
         71 . The lid of  claim 70 , wherein a valve member engages the valve rim portion in a closed position of the valve. 
     
     
         72 . The lid of  claim 71 , wherein the valve member comprises a disc. 
     
     
         73 . The lid of  claim 71 , wherein a first magnetic force maintains the valve member engaged with the valve rim portion. 
     
     
         74 . The lid of  claim 73 , wherein a second magnetic force maintains the valve in the open position, and wherein the first magnetic force is greater than the second magnetic force. 
     
     
         75 . The lid of  claim 70 , wherein the fluid vessel comprises a drinking cup, and wherein a user can drink from any side of a periphery of the valve aperture. 
     
     
         76 . The lid of  claim 70 , wherein the lid covers an opening of the fluid vessel, and wherein the valve aperture has a substantially same size as the opening of the fluid vessel. 
     
     
         77 . A lid for a fluid vessel, comprising:
 a valve disc;   first and second valve seats positioned on opposite sides of the valve disc;   in a closed position, a periphery of the valve disc engages a valve rim portion of the first valve seat, wherein the valve rim portion circumscribes a valve aperture; and   in an open position, the valve disc engages the second valve seat and permits relatively unobstructed flow through the valve aperture.   
     
     
         78 . The lid of  claim 77 , wherein a first magnetic force maintains the valve disc engaged with the first valve seat in the closed position. 
     
     
         79 . The lid of  claim 78 , wherein a second magnetic force maintains the valve disc engaged with the second valve seat in the open position. 
     
     
         80 . The lid of  claim 79 , wherein the first magnetic force is greater than the second magnetic force. 
     
     
         81 . The lid of  claim 77 , wherein the valve disc comprises a plastics material impregnated with a magnetic material. 
     
     
         82 . The lid of  claim 77 , wherein at least one of the first and second valve seats comprises a plastics material impregnated with a magnetic material. 
     
     
         83 . The lid of  claim 77 , wherein a fluid flows through the valve aperture, irrespective of a rotational orientation of the lid, when the valve disc is in the open position and the vessel is tilted from an upright position.