Digital fluid flow control apparatus

Claim 2

Digital fluid flow control apparatus comprising: a fluid inlet having an inlet axis that lies approximately in a flow plane; a fluid outlet having an outlet axis that lies approximately in the flow plane; a housing having an upstream manifold to which the inlet is connected, a downstream manifold to which the outlet is connected, and a planar partition between the upstream and downstream manifolds, the partition lying at an acute angle to the flow plane; and a plurality of individually actuatable bistable valve elements connecting the upstream and downstream manifolds across the partition.

Claim 3

The apparatus of claim 1, in which one of the manifolds has a side wall opposite to the partition that is approximately parallel to the flow axis.

Claim 4

The apparatus of claim 2, in which the other manifold has a side wall opposite to the partition that is approximately parallel to the partition.

Claim 5

The apparatus of claim 1, in which one of the manifolds has a side wall opposite to the partition that is approximately parallel to the partition.

Claim 6

The apparatus of claim 1, in which the housing comprises an outer casing having an open cavity with a side wall and an end wall, and a core removably fitting in the cavity, the core having an annular groove defining with the side wall of the cavity one of the manifolds, and having an end wall spaced from the end wall of the cavity to define the other manifold the portion of the core between the groove and the end wall of the core forming the partition.

Claim 7

The apparatus of claim 5, additionally comprising means for removably mounting the valve elements onto the core in a parallel arrangement.

Claim 8

The apparatus of claim 6, in which for each valve element a pair of unthreaded axially aligned bores are formed in the core portions of the bore on opposite sides of the annular groove, and the means for removably mounting each valve element comprises a shoulder on such valve element that contacts an abutting surface of the core when such valve element is mounted onto the core and means for clamping the valve element against the abutting surface.

Claim 9

The apparatus of claim 7, in which the abutting surface comprises a surface of the groove adjacent to the bore through the portion of the bore forming the partition.

Claim 10

Digital fluid flow control apparatus having an upstream manifold, a downstream manifold, and a plurality of individually actuatable bistable valve elements connecting the upstream and downstream manifolds, the improvement characterized in that the valve elements each comprise in one of the manifolds: a stationary hollow inner cage having a perforated side wall permitting communication between the inside and outside of the inner cage; a movable plug surrounding the inner cage and axially slidable thereover to cover and uncover the side wall perforations of the inner cage; a stationary hollow outer cage surrounding the plug, the outer cage having a perforated side wall permitting communication between the inside and outside of the outer cage; means for sealing the interface between the side wall perforations in one of the cages and the plug when the plug covers the side wall perforations in the inner cage; a tubular passage coupling the open end of the inner cage to the other manifold; and a converging-diverging nozzle formed in the tubular passage.

Claim 11

Digital fluid flow control apparatus having an upstream manifold, a downstream manifold, and a plurality of individually actuatable bistable valve elements connecting the upstream and downstream manifolds, the improvement characterized in that the valve elements each comprise in one of the manifolds: a stationary hollow inner cage having a perforated side wall permitting communication between the inside and outside of the inner cage; a movable plug surrounding the inner cage and axially slidable thereover to cover and uncover the side wall perforations of the inner cage; a stationary hollow outer cage surrounding the plug, the outer cage having a perforated side wall permitting communication between the inside and outside of the outer cage; means for sealing the interface between the side wall perforations in one of the cages and the plug when the plug covers the side wall perforations in the inner cage; a tubular passage coupling the open end of the inner cage to the other manifold; and a converging-diverging nozzle formed in the tubular passage.

Claim 12

The apparatus of claim 9, in which the plug fits closely about the inner cage, the outer cage fits closely about the plug, the inner cage is closed at one end and open at the other end for communication with the other manifold, and the sealing means comprises an O-ring retained in the side wall of the inner cage near its closed end to engage the inner side wall of the plug and a face seal retained by the inner cage near its open end to engage the end of the plug when the plug covers the side wall perforations in the inner cage.

Claim 13

Digital fluid flow control apparatus having a housing with an upstream manifold to which the inlet is connected, a downstream manifold to which the outlet is connected, and a plurality of bores extending in part between the upstream and downstream manifolds; a fluid inlet in the housing to the upstream manifold; a fluid outlet in the housing to the downstream manifold; and a plurality of individually actuatable bistable valve elements fitting in the respective bores and connecting the upstream and downstream manifolds, characterized in that: each bore is unthreaded; each valve element has a shoulder that contacts an abutting surface of the housing when such valve element fits in the respective bore; and each valve element has means for removably clamping the valve element against the abutting surface, the clamping means comprising a resilient washer and a snap ring at the entrance of each bore.

Claim 14

Digital fluid flow control apparatus having a housing with an upstream manifold to which the inlet is connected, a downstream manifold to which the outlet is connected, and a plurality of bores extending in part between the upstream and downstream manifolds; a fluid inlet in the housing to the upstream manifold; a fluid outlet in the housing to the downstream manifold; and a plurality of individually actuatable bistable valve elements fitting in the respective bores and connecting the upstream and downstream manifolds, characterized in that: each bore is unthreaded; each valve element has a shoulder that contacts an abutting surface of the housing when such valve element fits in the respective bore; and each valve element has means for removably clamping the valve element against the abutting surface, the clamping means comprising a resilient washer and a snap ring at the entrance of each bore.

Claim 15

The apparatus of claim 11, in which the clamping means comprises a flange on each valve element outside the entrance to the respective bore adjacent to the housing, and means for fastening the flange to the housing.