Patent ID: 6837257

Claim:
Valve device at dispensers which are adapted for dispensing portions of liquid or semi-liquid products ( 2 ), preferably foodstuff, from containers, and which have vacuum pumps ( 5 ) for generating a negative pressure in passage systems ( 6 ) through which the products ( 2 ) are dispensed from the containers, characterized in that the valve device is a magnetic valve device ( 9 ) which is designed as a permanent magnet device which is provided to generate two magnetic fields (M 1 , M 2 ) for providing retaining forces (P 1 , P 2 ) for retaining a valve body ( 9 d ) in a valve position (L 2 ) in a passage ( 6 a ) in the passage system ( 6 ) between a first container ( 3 ) and the vacuum pump ( 5 ) or another valve position (L 1 ) in another passage ( 6 b ) in the passage system ( 6 ) between a second container ( 4 ) and the vacuum pump ( 5 ), that the valve body ( 9 d ) is movable or displaceable between said two valve positions (L 2 , L 1 ) for keeping one of the passages ( 6 a or 6 b ) open and the other passage ( 6 a or 6 b ) closed, and that the vacuum pump ( 5 ) is provided to increase the pressure in an open passage ( 6 a ) when the container ( 3 ) connected thereto is empty and thereby generate such a pressure differential on opposite sides of the valve body ( 9 d ) that said valve body ( 9 d ) is subjected to displacement forces (F 1 or F 2 ) which are greater than the retaining forces (P 1 or P 2 ) for moving or displacing it from one valve position (L 1 ) to the other valve position (L 2 ) or vice versa and thereby opening a closed passage ( 6 b or 6 a ) such that the vacuum pump ( 5 ) can bring the product ( 2 ) to flow from a second container ( 4 ) containing the product ( 2 ) to flow from a second container ( 4 ) containing the product ( 2 ) when the other ( 3 ) of said containers ( 3 , 4 ) is empty.