초록 ▼

A fluid pressure controlling unit including a housing defining at least one substantially fluid tight chamber having first, second and third ports. An arm is disposed, at least in part, in the at least one substantially fluid tight chamber and is capable of being moved between positions which close

A fluid pressure controlling unit including a housing defining at least one substantially fluid tight chamber having first, second and third ports. An arm is disposed, at least in part, in the at least one substantially fluid tight chamber and is capable of being moved between positions which close either the first or the second port. A spring biases the arm to close either the second port or the first port (preferably the second port). An electrically actuable device is capable of moving the arm to close the first port. When the arm closes the second port, the first and the third ports are in communication via the chamber(s), and, when the arm closes the first port, the second and the third ports are in communication via the chamber(s).

대표청구항 ▼

A pulsator unit for incorporation into a milking machine said pulsator unit comprising: housing means defining a chamber having a first, second and third port, said first and second ports being provided with a valve seat inside said chamber, arm means mounted for movement within the chamber of said

A pulsator unit for incorporation into a milking machine said pulsator unit comprising: housing means defining a chamber having a first, second and third port, said first and second ports being provided with a valve seat inside said chamber, arm means mounted for movement within the chamber of said housing means, said arm means having a distal end region movable so that each of two opposite sides of said distal end region is seatable on only one said valve seat of said first and second ports at any one time to close only one of said first and second ports, biasing means for biasing said arm means to close one of said first port and said second port, and electrically actuable means for moving said arm means to open said one of said first and second ports closed by said biasing means acting on said arm means and to close the other of said first and second ports so that when said arm means closes said second port, said first and third ports are in communication via said chamber, and, when said arm means closes said first port, said second and third ports are in communication via said chamber, said electrically actuable means having at least one pair of electrical connections engageable externally of said chamber of said housing means, said first and third ports being located on a common side of said housing means to allow a plug engagement of the pulsator unit into a receiver which provides a vacuum source to said first port and a connection to said third port while the second port is connectable to or vents from a gas source.