Multiplex reciprocating pump
View Patent ↗A reciprocating pump assembly comprises: a motor with a rotary motor drive shaft; a cam coupled to the motor drive shaft with an axis of rotation and a cam channel cut generally axially into a radial face of the cam; and multiple reciprocating pump units arranged radially about the cam axis of rotation, each with an inlet valve, an outlet valve, a plunger and a plunger sleeve, with a free end of its plunger coupled to the cam by way of a cam follower riding in the cam channel; wherein rotation of the motor output drive shaft causes the plunger in each pump unit to independently reciprocate in its respective sleeve.
1. A reciprocating pump assembly that comprises:
a motor with a rotary motor drive shaft;
a cam coupled to the motor drive shaft, the cam having a circular perimeter, a cam axis of rotation and a cam channel that cuts generally axially into a radial face of the cam and has a cam channel path that is generally parallel to the perimeter of the cam and eccentric relative to the cam axis of rotation; and
multiple reciprocating pump units arranged radially about the cam axis of rotation, each with an inlet valve, an outlet valve, a plunger and a plunger sleeve, with a free end of its plunger coupled to the cam by way of a cam follower riding in the cam channel along the cam channel path;
wherein rotation of the motor output drive shaft causes the plunger in each pump unit to reciprocate in its respective plunger sleeve.
2. The pump assembly of claim 1 , wherein the motor comprises an electric motor.
3. The pump assembly of claim 2 , wherein the electric motor comprises a direct current (DC) motor.
4. The pump assembly of claim 1 , further comprising a reduction gear set for coupling the motor to the cam.
5. The pump assembly of claim 4 , wherein the reduction gear set comprises a spur-type gear set.
6. The pump assembly of claim 4 , wherein the reduction gear set comprises a two-stage reduction gear set.
7. The pump assembly of claim 1 , wherein each plunger has a diameter and the reduction gear set has a gear reduction ratio that matches the torque requirement of the pump assembly to the motor.
8. The pump assembly of claim 1 , wherein the cam channel drives each cam follower at a generally constant absolute speed.
9. The pump assembly of claim 1 , wherein each plunger comprises a ceramic material.
10. The pump assembly of claim 1 , wherein each plunger sleeve comprises stainless steel.
11. The pump assembly of claim 1 , wherein each plunger sleeve comprises composite TFE bearings.
12. The pump assembly of claim 1 , wherein each plunger sleeve comprises composite TFE seals.
13. The pump assembly of claim 1 , wherein each inlet valve comprises a ball-type check valve.
14. The pump assembly of claim 13 , wherein each inlet valve comprises composite TFE seats.
15. The pump assembly of claim 1 , wherein each outlet valve comprises a spring-loaded ball-type check valve.
16. The pump assembly of claim 1 , wherein each outlet valve comprises composite TFE seats.
17. A reciprocating pump assembly that comprises:
an electric motor with a rotary motor drive shaft;
a cam that has a circular perimeter, a cam axis of rotation and a cam channel that cuts generally axially into a radial face of the cam and has a cam channel path that is generally parallel to the perimeter of the cam and eccentric relative to the cam axis of rotation;
a gear reduction set that couples the motor drive shaft to the cam; and
multiple reciprocating pump units arranged radially about the cam axis of rotation, each with an inlet valve, an outlet valve, a ceramic plunger and a stainless steel plunger sleeve, with a free end of its plunger coupled to the cam by way of a cam follower riding in the cam channel along the cam channel path;
wherein rotation of the motor output drive shaft causes the plunger in each pump unit to reciprocate in its respective plunger sleeve at a generally constant absolute speed.
18. The pump assembly of claim 17 , wherein each plunger has a diameter and the reduction gear set has a gear reduction ratio that matches the torque requirement of the pump assembly to the motor.
19. The pump assembly of claim 17 , wherein each plunger sleeve comprises composite TFE bearings and seals.
20. The pump assembly of claim 17 , wherein each inlet valve comprises a ball-type check valve with composite TFE seats and each outlet valve comprises a spring-loaded ball-type check valve with composite TFE seats.
21. A reciprocating pump assembly that comprises:
an electric direct current (DC) motor with a rotary motor drive shaft;
a cam that has a circular perimeter, a cam axis of rotation and a cam channel that cuts generally axially into a radial face of the cam and has a cam channel path that is generally parallel to the perimeter of the cam and eccentric relative to the cam axis of rotation;
a gear reduction set that couples the motor drive shaft to the cam; and
two reciprocating pump units arranged in a radially opposed configuration about the cam axis of rotation, each with a ball-type inlet valve, a spring-loaded ball-type outlet valve, a ceramic plunger and a stainless steel plunger sleeve, with a free end of its plunger coupled to the cam by way of a cam follower riding in the cam channel along the cam channel path;
wherein rotation of the motor output drive shaft causes the plunger in each pump unit to reciprocate in its respective plunger sleeve at a generally constant absolute speed.
22. The pump assembly of claim 21 , wherein each plunger has a diameter and the reduction gear set has a gear reduction ratio that matches the torque requirement of the pump assembly to the motor.
23. The pump assembly of claim 21 , wherein each plunger sleeve comprises composite TFE bearings, each inlet valve comprises composite TFE seats and each outlet valve comprises composite TFE seats.