Reciprocating pump control system

Claim 2

A control system for a pulse-minimizing pumping system utilizing a first reciprocating pump and a second reciprocating pump for pumping fluid from a fluid source to a fluid output manifold, comprising, in combination: pump biasing means including a first fluid means for biasing said first pump forwardly, a second fluid means for biasing said second pump forwardly, and means for continuously reverse biasing both of said pumps, first valve means responsive to the movement of said second pump for actuating said first fluid biasing means when said second pump is in a prescribed position of the forward stroke thereof, second valve means responsive to the movement of said first pump for actuating said second fluid biasing means when said first pump is in a prescribed position of the forward stroke thereof, first fluid time delay means activated by said first valve means and providing means for deactivating said second biasing means at a predetermined time after said second pump passes the prescribed position of the forward stroke thereof, and second fluid time delay means activated by said first valve means and providing means for deactivating said first biasing means at a predetermined time after said first pump passes the prescribed position of the forward stroke thereof such that at least one of said pumps is always forwardly moving thereby masking out any reverse stroke pulse from the other pump.

Claim 3

The system as set forth in claim 1 including first and second control cylinders and first and second drive pistons within said cylinders, said pistons drivingly connected to said first and second pumps respectively.

Claim 4

The combination as set forth in claim 2 wherein said reverse biasing means comprises a source of fluid under pressure, said source connected to each of said cylinders at the forward ends thereof such that said pistons are continuously reverse biased.

Claim 5

The combination as set forth in claim 2 wherein each of said forwardly biasing means comprises an accumulator and a NOT logic element, the output port of said accumulator being connected to one of the input ports of said NOT logic element, said NOT logic element also having a second input port connected to a source of fluid under pressure and an output port connected to one of the control cylinders for forwardly biasing the drive piston within said control cylinder such that the output of said NOT logic element is pressurized when the input from said accumulator is depressurized and such that the output of the NOT logic element is depressurized when the input from said accumulator is pressurized.

Claim 6

The combination as set forth in claim 4 wherein each of said delaying means comprises a restrictor connected between the output of the NOT logic element fOr one of said forwardly biasing means and the input for the accumulator for the other of said forwardly biasing means such that when the output of the NOT logic element for one of said forwardly biasing means is pressurized to forwardly bias one of said pistons and associated pump, the other of said NOT logic elements is depressurized after a delay time sufficient for the fluid to flow through the one restrictor and fill the other accumulator.

Claim 7

The system as set forth in claim 1 wherein each of said valves includes first, second and third fluid flow ports and a limit arm adapted to interconnect said first and second ports when the arm is actuated and to interconnect said first and third ports when the arm is not actuated.

Claim 8

The combination as set forth in claim 6 wherein the second port of each of said valves is connected to the input of the associated biasing means and the third port of each of the valves is connected to the atmosphere to allow bleeding of pressure from the valve.

Claim 9

The combination as set forth in claim 7 wherein the first ports of each of said valves are interconnected.

Claim 10

An improved fluid control system for alternately driving first and second reciprocating pumps to provide a non-pulsing single output comprising, in combination: a first pump having a reciprocating piston with a drive rod attached thereto for operating a pump; a second pump having a reciprocating piston with a drive rod attached thereto for operating a pump, each of said pistons having a forward pumping stroke and a return stroke said pumps providing a single output; fluid supply means; means for returning said pistons on said return stroke; first sensor means for sensing a prescribed position of said first piston; second sensor means for sensing a prescribed position of said second piston; first valve means connecting said fluid supply means to said first pump, said first valve means operated in response to said second sensor means to open fluid supply means to said first piston for driving said first piston in the forward pumping stroke; second valve means connecting said fluid supply means to said second pump, said second valve means operated in response to said first sensor means to open fluid supply means to said second piston for driving said second piston in the forward pumping stroke; first time delay valve control means for sensing supply pressure to said first piston from said first valve means, said first time delay valve control means operating to close said second valve means and thereby stop fluid supply to said second piston subsequent to a time interval so that said return means operates to return said second piston by said return stroke; and second time delay valve control means for sensing supply pressure to said second piston means from said second valve means; said second time delay valve control means operating to close said first valve means and thereby stop fluid supply to said first piston subsequent to a time interval so that said return means operates to return said first piston by said return stroke.

Claim 11

An improved fluid control system for alternately driving first and second reciprocating pumps to provide a non-pulsing single output comprising, in combination: a first pump having a reciprocating piston with a drive rod attached thereto for operating a pump; a second pump having a reciprocating piston with a drive rod attached thereto for operating a pump, each of said pistons having a forward pumping stroke and a return stroke said pumps providing a single output; fluid supply means; means for returning said pistons on said return stroke; first sensor means for sensing a prescribed position of said first piston; second sensor means for sensing a prescribed position of said second piston; first valve means connecting said fluid supply means to said first pump, said first valve means operated in response to said second sensor means to open fluid supply means to said first piston for driving said first piston in the forward pumping stroke; second valve means connecting said fluid supply means to said second pump, said second valve means operated in response to said first sensor means to open fluid supply means to said second piston for driving said second piston in the forward pumping stroke; first time delay valve control means for sensing supply pressure to said first piston from said first valve means, said first time delay valve control means operating to close said second valve means and thereby stop fluid supply to said second piston subsequent to a time interval so that said return means operates to return said second piston by said return stroke; and second time delay valve control means for sensing supply pressure to said second piston means from said second valve means; said second time delay valve control means operating to close said first valve means and thereby stop fluid supply to said first piston subsequent to a time interval so that said return means operates to return said first piston by said return stroke.

Claim 12

The improved control system of claim 9 wherein said first and second sensor means are interconnected to provide identical control output signals whenever the prescribed position of said first and second pistons is substantially the same.

Claim 13

The control system of claim 9 wherein said first valve means and said second valve means comprise fluid operative NOT devices.

Claim 14

The control system of claim 9 wherein said first and second time delay valve control means comprise restrictors.

Claim 15

The apparatus of claim 9 wherein said first and second time delay means comprise accumulators.

Claim 16

The apparatus of claim 9 wherein said piston rods include indicia and said first and second sensor means include means for sensing said indicia.

Claim 17

A control system for a pulse minimizing pumping system utilizing first and second separate pumps which pump fluid from a single outlet means, each Of said pumps having a forward pumping stroke to said outlet means and a reverse stroke comprising, in combination: means for biasing each of said pumps in the direction of said reverse stroke; forward stroke biasing means for each of said pumps; first and second means for sensing the extent of the forward stroke of said first and second pumps respectively; first and second switch means operable respectively by said second and first means for sensing, said first switch means operable to initiate operation of said forward stroke biasing means for said second pump and said second switch means operable to initiate operation of said forward stroke biasing means of the first pump; and first and second time delay means for sensing the forward stroke of said first and second pumps respectively and for subsequently deactivating said forward stroke biasing means for said second and first pumps respectively to permit simultaneous forward stroking by each pump prior to the reverse stroke by one of the pumps.

Claim 18

A control system for a pulse minimizing pumping system utilizing first and second separate pumps which pump fluid from a single outlet means, each Of said pumps having a forward pumping stroke to said outlet means and a reverse stroke comprising, in combination: means for biasing each of said pumps in the direction of said reverse stroke; forward stroke biasing means for each of said pumps; first and second means for sensing the extent of the forward stroke of said first and second pumps respectively; first and second switch means operable respectively by said second and first means for sensing, said first switch means operable to initiate operation of said forward stroke biasing means for said second pump and said second switch means operable to initiate operation of said forward stroke biasing means of the first pump; and first and second time delay means for sensing the forward stroke of said first and second pumps respectively and for subsequently deactivating said forward stroke biasing means for said second and first pumps respectively to permit simultaneous forward stroking by each pump prior to the reverse stroke by one of the pumps.

Claim 19

A pneumatic control system for a pulse minimizing pumping system of the type including first and second separate pumps which pump through a single outlet means, said pumps each having a forward stroke and a reverse stroke comprising, in combination: fluid means for continuously biasing said pumps in the direction of one stroke; fluid means for each of said pumps for intermittently biasing and driving each of said pumps in the direction of the other stroke; separate means for each of said pumps for sensing a predetermined change in said other stroke, each of said means for sensing including means for operating said means for intermittently biasing upon sensing said predetermined change, and time delay means operative to terminate said means for intermittently biasing subsequent to the initiation of the of the other stroke by said means for intermittently biasing, said means for sensing associated with said first pump operative to initiate the other stroke of said second pump and subsequently terminate the one stroke of said first pump, said means for sensing associated with said second pump operative to initiate the other stroke of said first pump and subsequently terminate the one stroke of said second pump.

Claim 20

A pneumatic control system for a pulse minimizing pumping system of the type including first and second separate pumps which pump through a single outlet means, said pumps each having a forward stroke and a reverse stroke comprising, in combination: fluid means for continuously biasing said pumps in the direction of one stroke; fluid means for each of said pumps for intermittently biasing and driving each of said pumps in the direction of the other stroke; separate means for each of said pumps for sensing a predetermined change in said other stroke, each of said means for sensing including means for operating said means for intermittently biasing upon sensing said predetermined change, and time delay means operative to terminate said means for intermittently biasing subsequent to the initiation of the of the other stroke by said means for intermittently biasing, said means for sensing associated with said first pump operative to initiate the other stroke of said second pump and subsequently terminate the one stroke of said first pump, said means for sensing associated with said second pump operative to initiate the other stroke of said first pump and subsequently terminate the one stroke of said second pump.