Ball cage with directed flow paths for a ball pump

1. A pump ( 10 ) for pumping heavily filled material containing a fluid and heavy fillers, aggregates, cementitious material, or similar constituents that can separate under pressure, the pump comprising:

an outlet port ( 12 );

an outlet section ( 14 ) in fluid communication with the outlet port;

an inlet port ( 16 );

a ball cage ( 20 ), comprising:

a first ball ( 28 ) disposed therewithin;

spaced apart opposing first and second ends ( 30 , 32 ) that operate as ball stops for the first ball ( 28 );

a first opening ( 34 ) at the first end ( 30 ) of the ball cage, the first opening in fluid communication with the inlet port; and

a second opening ( 36 ) at the second end ( 32 ) of the ball cage, wherein the second opening ( 36 ) has a central portion and plurality of circumferentially spaced smaller openings ( 38 ) extending outward from the central portion, wherein when the first ball is stopped by the second end, the central portion of the second opening ( 36 ) is blocked by the first ball ( 28 ) and the smaller openings ( 38 ) are not blocked by the first ball ( 28 );

a plurality of passages ( 40 ) within the ball cage, each passage ( 40 ) being connected at one end to one of the plurality of smaller openings ( 38 ) and each passage being defined at least in part by the first ball and by an inner wall of the ball cage ( 20 ), so that material entering the pump ( 18 ) through the inlet port ( 16 ) flows into the ball cage ( 20 ) through the first opening ( 34 ) and along the passages ( 40 ) to exit the ball cage ( 20 ) through the smaller openings ( 38 ) of the second opening ( 36 ) at the second end ( 32 ), wherein a cross-sectional area of the passages decreases with increasing distance from the first opening ( 34 ), so that a velocity of material flowing through the passages ( 40 ) increases with increasing distance from the first opening ( 34 ) to the smaller openings ( 38 ) of second opening ( 36 ) at the second end ( 32 ) of the ball cage ( 20 );

wherein the increase in the velocity flushes away compressed or hardened material out of the ball cage to prevent packing out; and

wherein, the ball cage is configured for uninhibited displacement of the first ball within the ball cage between the first and second ends ( 30 , 32 );

a first seat ( 58 ) at the first end of the ball cage ( 20 ); and

a substantially hollow middle section ( 24 ) extending between the outlet section ( 14 ) and the ball cage ( 20 ), the middle section ( 24 ) in fluid communications with the outlet section ( 14 ) and with the second opening ( 36 );

wherein material flows from the inlet port ( 16 ) through the first opening ( 34 ) into the passages ( 40 ) and through the second opening ( 36 ) into the middle section ( 24 );

wherein a pressure applied on the first ball in a first direction sealingly seats the first ball on the seat, thereby inhibiting flow of material across the first opening;

wherein a pressure applied on the first ball in a second direction unseats the first ball from the seat and positions the first ball on the central portion of the second opening;

wherein material in the middle section flows into the outlet section; and

wherein material in the outlet section flows out of the pump through the outlet port.

2. The pump of claim 1 , wherein the pressure in the second direction is due to one or more of:

a pressure in the ball cage that is relatively higher than a pressure in the middle section;

a pressure at the inlet port that is relatively higher than the pressure in the ball cage; and

flow of material from the inlet port into the ball cage through the first opening.

3. The pump of claim 1 , wherein the increase in the velocity flushes away compressed or hardened material out of the ball cage to prevent packing out.

4. The pump of claim 1 , wherein material in the outlet section flows out of the pump through the outlet port.

5. The pump of claim 1 , wherein the first ball comprises a substantially compliant coating ( 72 ) encasing a substantially rigid core ( 74 ).

6. The pump of claim 1 , further comprising:

an inlet section ( 18 ) in fluid communication with the inlet port; wherein the middle section ( 24 ) extends between and in fluid communication with the inlet and outlet sections;

a ball guide ( 22 ) comprising a second ball ( 54 ) disposed therewithin; and

a piston ( 26 ) configured for displacing the ball guide towards and away from the ball cage ( 20 ).

7. The pump of claim 6 , further comprising:

a second seat ( 60 ) disposed at an end of the ball guide;

wherein,

the first ball disposed within the ball cage is a compliant ball;

the ball cage, the first ball disposed therewithin, and the seat disposed at an end of the ball cage are configured as a check valve;

the second ball disposed within the ball guide is a compliant ball; and

the ball guide, the second ball disposed therewithin, and the seat disposed at an end of the ball guide are configured as a check valve.

8. The pump of claim 7 , wherein each of the compliant first and second balls disposed within the ball cage and the ball guide, respectively comprises:

a substantially rigid core ( 74 ); and

a compliant coating ( 72 ) encasing the rigid core.