Process pump having a crank drive
The present invention relates to a process pump having a crank mechanism ( 1 ) and at least three cylinders that represent a first cylinder, a second cylinder and a third cylinder when seen clockwise or counterclockwise around the crank mechanism ( 1 ), wherein the crank mechanism ( 1 ) has a vertical crankshaft and for each cylinder a crosshead ( 7, 10, 13 ) each and a connecting rod ( 8, 11, 14 ), each having a large connecting rod top end ( 8 a, 11 a ) for receiving the crankshaft, wherein the crossheads ( 7, 10, 13 ) are functionally connected to the crankshaft via the connecting rods ( 8, 11, 14 ). The invention is characterized in that the crankshaft is formed as an eccentric shaft ( 5 ) with a first eccentric and a second eccentric, wherein the connecting rod ( 8 ) of the first cylinder and the connecting rod ( 14 ) of the third cylinder are arranged on the first eccentric, and wherein the connecting rod ( 11 ) of the second cylinder is arranged on the second eccentric, so that the large connecting rod top end ( 8 a ) of the connecting rod ( 8 ) of the first cylinder and the large connecting rod top end of the connecting rod ( 14 ) of the third cylinder have a common central axis.
1. A process pump ( 100 ) having a crank mechanism ( 1 ) and at least three cylinders ( 2 , 3 , 4 ) that when seen around the crank mechanism ( 1 ) represent a first cylinder ( 2 ), a second cylinder ( 3 ) and a third cylinder ( 4 ), wherein the crank mechanism ( 1 ) has a crankshaft and for each cylinder ( 2 , 3 , 4 ) a crosshead ( 7 , 10 , 13 ) and a connecting rod ( 8 , 11 , 14 ), each connecting rod having a large connecting rod top end ( 8 a , 11 a , 14 a ) being received by the crankshaft, wherein the crossheads ( 7 , 10 , 13 ) are functionally connected to the crankshaft via the connecting rods ( 8 , 11 , 14 ),
characterized in that
the crankshaft is formed as an eccentric shaft ( 5 ) with a first eccentric ( 15 ) and a second eccentric ( 16 ), wherein the connecting rod ( 8 ) of the first cylinder ( 2 ) and the connecting rod ( 14 ) of the third cylinder ( 4 ) are arranged on the first eccentric ( 15 ), and wherein the connecting rod ( 11 ) of the second cylinder ( 3 ) is arranged on the second eccentric ( 16 ), so that the large connecting rod top end ( 8 a ) of the connecting rod ( 8 ) of the first cylinder ( 2 ) and the large connecting rod top end ( 14 a ) of the connecting rod ( 14 ) of the third cylinder ( 4 ) have a common central axis ( 17 );
a plurality of axes ( 20 , 21 , 22 ) of adjacent cylinders ( 2 , 3 , 4 ) have an angular offset (W 1-2 , W 2-3 ) of 60° to each other, wherein each of the plurality of axes are projected onto a common plane disposed perpendicularly to a rotational axis of the eccentric shaft;
the angular offset (W 1-3 ) between the axis ( 20 ) of the first cylinder ( 2 ) and the axis ( 22 ) of the third cylinder ( 4 ) is 120°;
a balancing mass ( 24 ) is arranged on the eccentric shaft ( 5 ); and
the first eccentric ( 15 ) and the second eccentric ( 16 ) are arranged on the eccentric shaft ( 5 ) by an offset of 180°, wherein the common plane has a vertical and a horizontal axis ( 21 ) in which the vibrations are reduced.
2. The process pump ( 100 ) according to claim 1 , characterized in that the process pump ( 100 ) has exactly three cylinders ( 2 , 3 , 4 ).
3. The process pump ( 100 ) according to claim 1 ,
characterized in that at least one of the two eccentrics ( 15 , 16 ), is formed as an eccentric disc.
4. The process pump ( 100 ) according to claim 1 ,
characterized in that
the connecting rods ( 8 , 11 , 14 ) each have a connecting rod shank ( 8 b , 11 b , 14 b ) and a small connecting rod top end ( 8 c , 11 c , 14 c ) for functional connection with the crossheads ( 7 , 10 , 13 ), wherein the large connecting rod top end ( 8 a , 11 a , 14 a ), the connecting rod shank ( 8 b , 11 b , 14 b ), and the small connecting rod top end ( 8 c , 11 c , 14 c ) are formed as one piece.
5. The process pump ( 100 ) according to claim 1 ,
characterized in that
the eccentric shaft ( 5 ) is formed as one piece.
6. The process pump ( 100 ) according to claim 1 ,
characterized in that the balancing mass ( 24 ) is the only balancing mass arranged on the eccentric shaft ( 5 ).
7. The process pump ( 100 ) according to claim 1 ,
characterized in that
the process pump ( 100 ) has at least one pump head formed as a single-acting ( 102 a , 103 a , 104 a ) or double-acting pump head ( 102 , 103 , 104 ).
8. The process pump ( 100 ) according to claim 1 , characterized in that both of the two eccentrics ( 15 , 16 ), are each formed as a respective eccentric disc.
9. The process pump ( 100 ) according to claim 1 , characterized in that the eccentric shaft is configured for receiving the balancing mass upstream of the first cylinder when viewed in an axial direction.
10. The process pump ( 100 ) according to claim 1 , wherein the balancing mass comprises a radially acting fastening element to secure the balancing mass on the eccentric shaft.