| 主权项 |
1. Apparatus comprising
a longitudinally elongated bar having a longitudinal axis, a first end and a second end, a housing defining a longitudinal passage having a longitudinal axis, said longitudinal passage slidably receiving the longitudinally elongated bar, so that the longitudinal axis of the passage coincides with the longitudinal axis of the bar, wherein the bar defines first, second and third bar cross-passages each extending transversely through the bar from a first face to an opposite second face, the first transverse bar cross-passage crossing between the first end and the second end of the bar, the second transverse bar cross-passage crossing between the first transverse bar cross-passage and the second end, and the third transverse bar cross-passage crossing between the first transverse bar cross-passage and the second transverse bar cross-passage, said third transverse bar cross-passage being of a much smaller diameter than the first bar cross-passage or the second bar cross-passage, said first and third bar cross-passages extending from an inlet on the first face of the bar to an outlet on the second face of the bar, said second bar cross-passage extending from an inlet on the second face of the bar to an outlet on the first face of the bar, wherein the housing defines first, second and third housing lateral penetration passages each extending transversely from an outer surface of the housing to the longitudinal passage, said first and second housing lateral penetration passages being spaced apart longitudinally apart from each other, said first housing lateral penetration passage extending from an inlet on the first lateral side of the housing to an outlet at the longitudinal passage, said second lateral penetration passage extending from an inlet at the longitudinal passage to an outlet on the first lateral side of the housing, and said third housing lateral penetration passage extending from a second lateral side of the housing opposite from the first lateral side of the housing to the longitudinal passage, said third housing lateral penetration passage intersecting the longitudinal passage at a longitudinal position across from a point between the first and second housing penetration passages, wherein at least one of the housing and the bar defines a longitudinal groove to maintain the third housing lateral penetration passage in flow communication with all three of the cross passages though the bar, wherein the bar is positionable in first, second, third and fourth positions, wherein when the bar is in the first position, the inlet to the third cross-passage is in peripherally sealed flow communication with the outlet of the first lateral penetration and the inlet to the second lateral penetration is sealed off by the first face of the bar, wherein when the bar is in the second position, the inlet to the first cross-passage through the bar is in peripherally sealed flow communication with the outlet of the first lateral penetration passage and the inlet to the second lateral penetration is sealed off by the first face of the bar, wherein when the bar is in the third position, the outlet of the first lateral penetration passage and the inlet to the second lateral penetration passage is sealed off by the first face of the bar; and wherein when the bar is in the fourth position, the outlet to the first lateral penetration passage is sealed off by the first face of the bar and the inlet to the second lateral penetration is in peripherally sealed flow communication with the second cross-passage through the bar. |
