US20170335832A1

US20170335832A1 - Pump System for Inline Conditioning

Info

Publication number: US20170335832A1
Application number: US15/533,439
Authority: US
Inventors: Bjorn Markus Olovsson; Thomas Erik Arctaedius
Original assignee: GE Healthcare Bio Sciences Corp
Current assignee: Cytiva Sweden AB
Priority date: 2014-12-18
Filing date: 2015-12-17
Publication date: 2017-11-23
Also published as: WO2016097146A1

Abstract

A pump system is disclosed. The pump system includes a cavity (102) comprising one or more inlet check valves (120, 122) and one or more outlet check valves (124, 126). A piston (104) having an enlargement (106) at a substantially middle portion of the piston (104). The piston (104) is capable of moving within the cavity (102) for forming a first chamber (116) and a second chamber (118), wherein up movement of the piston (104) the volume in the first chamber (112) is increased and simultaneously the volume in the second chamber (118) is decreased and vice versa.

Description

FIELD OF THE INVENTION

The subject matter disclosed herein relates to supplying solutions using a pump system. More specifically the subject matter relates to a pump system for supplying solutions for inline conditioning.

BACKGROUND OF THE INVENTION

Numerous pumping system and mechanisms are used for supplying solutions for different purposes. The pumping system includes different pumps of varying capacity for supplying solutions at different flow rates. In current systems each pump is driven by a driving unit which makes the system complex for functioning and bulky.
Chromatography is a well-established and valuable technique for separating chemical and biological substances and is widely used in research and industry, finding many applications in compound preparation, purification and analysis. There are many different forms of chromatography, liquid chromatography being of particular importance in the pharmaceutical and biological industries for the preparation, purification and analysis of proteins, peptides and nucleic acids. A typical liquid chromatography apparatus has an upright housing in which a bed of packing material, which is usually particulate in nature and consists of a porous medium, rests against a permeable retaining layer. A liquid mobile phase enters through an inlet, for example at the top of the column, usually through a porous, perforated filter, mesh or frit, moves through the bed of packing material and is removed via an outlet, typically through a second filter, mesh or frit.
In many cases it is important to obtain liquids of precisely known composition and/or other characteristics, such as pH, ionic strength, viscosity, density etc. It is further not uncommon that the composition of the liquid should not only be at each moment precisely known and controlled, but also should vary with time in a precise and controlled manner Such liquids are usually obtained by mixing or blending two or more liquids with each other, typically using a blending system, usually an on-site blending system, which may provide for both isocratic and gradient blending modes (step gradient and linear gradient). One application where the composition of liquids is of utmost importance is in the field of liquid chromatography, when buffers having a specified pH and optionally also ionic strength are utilized, the pH and ionic strength of the eluent being the two most important parameters that control selectivity of protein separations in chromatography, such as on ion exchange resins. Another such application is filtration.
The current systems include usage of multiple pumps for supplying solutions for inline conditioning in a chromatography system. Each pump may have a multiple pump head and may be driven by a driving unit per pump head. The driving unit operates the pump to supply solutions for instance buffer solution to a chromatography column for purifying and separation of numerous proteins. However multiple driving units for each pump render the system more bulky and complex in operation.
Accordingly, a need exists for an improved pump system for supplying solutions for chromatography.

SUMMARY OF THE INVENTION

The object of the invention is to provide an improved way of pumping and supplying solutions, which overcomes one or more drawbacks of the prior art. This is achieved by an improved pump system having multiple pumps driven by one motor for supplying solutions for as defined in the independent claim.
One advantage with the disclosed pump system is that it has multiple pumps that can be driven by a single motor per pump for supplying solutions. In this pump system a single piston is configured to operate the flowing in of the solutions through inlet pumps and flowing out of the solutions through outlet check valves. The piston may be operated by one driving unit which renders the pump system to be simple in construction and operable with ease. Further in an inline conditioning application in chromatography the pump system facilitates efficient inline dilution and purification of proteins.
In an embodiment a pump system is disclosed. The pump system includes a cavity comprising one or more inlet check valves and one or more outlet check valves. A piston having an enlargement at a substantially middle portion of the piston. The piston is capable of moving within the cavity for forming a first chamber and a second chamber, wherein up movement of the piston the volume in the first chamber is increased and simultaneously the volume in the second chamber is decreased and vice versa.
In another embodiment an inline conditioning system is disclosed. The inline conditioning system includes a pump system includes a cavity including one or more inlet check valves and one or more outlet check valves. A piston present in the system has an enlargement at a substantially middle portion of the piston. The piston is capable of moving within the cavity for forming a first chamber and a second chamber, wherein up movement of the piston the volume in the first chamber is increased and simultaneously the volume in the second chamber is decreased and vice versa. When the piston moves a solution is filled into the cavity and simultaneously some solution is also supplied out from the cavity. The pump system is connected to buffer preparation unit configured to receive solution for buffer preparation.
A more complete understanding of the present invention, as well as further features and advantages thereof, will be obtained by reference to the following detailed description and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration of a pump system for supplying solutions according to an embodiment;

FIG. 2 is a schematic illustration of a pump system having a piston moving towards a first chamber in a cavity for supplying solutions according to an embodiment;

FIG. 3 is a schematic illustration of a pump system having a piston moving towards a second chamber in a cavity for supplying solutions according to an embodiment;

FIG. 4 is a schematic illustration of a pump system having a piston moving within a cavity and connected to a driving unit and a resilient unit according to an embodiment;

FIG. 5 is a schematic illustration of a pump system having a piston connected to an eccentric drive unit according to an embodiment;

FIG. 6 is a schematic illustration of a pump system having an extension at one end of the piston according to an embodiment; and

FIG. 7 illustrates an inline conditioning system according to an exemplary embodiment.

DETAILED DESCRIPTION OF THE INVENTION

In the following detailed description, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration specific embodiments that may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the embodiments, and it is to be understood that other embodiments may be utilized and that logical, mechanical and other changes may be made without departing from the scope of the embodiments. The following detailed description is, therefore, not to be taken as limiting the scope of the invention.
As discussed in detail below, embodiments of a pump system is disclosed. The pump system includes a cavity comprising one or more inlet check valves and one or more outlet check valves. A piston having an enlargement at a substantially middle portion of the piston. The piston is capable of moving within the cavity for forming a first chamber and a second chamber, wherein up movement of the piston the volume in the first chamber is increased and simultaneously the volume in the second chamber is decreased and vice versa.
FIG. 1 illustrates a pump system 100 for supplying solutions according to an embodiment. The pump system 100 includes a cavity 102 within which a piston 104 moves to and fro. The piston 104 may have an enlargement at a substantial middle portion. In an embodiment the piston 104 may have a middle portion 106 (i.e. the enlargement) with a larger dimension and extensions 108 and 110 provided at both sides of the middle portion 106. The extensions 108 and 110 may have a smaller dimension as compared to the middle portion 106. In an embodiment the middle portion 106 may have a larger circumference or perimeter as compared to circumference or perimeter of the extensions 108 and 110. The middle portion 106 and the extensions 108 and 110 may have cylindrical structure. In other embodiments the middle portion and the extensions 108 and 110 may have any other structures such as but not limited to a cuboid, cube, hexahedron and so on. In an embodiment the extensions 108 and 110 may have different structural configuration such as different dimensions. For instance the extension 108 may have a larger dimension as compared to the extension 110. Alternatively the extension 108 may be longer as compared to the extension 110. The extensions 102 and 110 may pass through and extends out of the cavity 102 at two ends as illustrated in FIG. 1.
The piston 104 may be connected to an end by a driving unit 112 for driving the piston 104. More specifically the driving unit 112 is connected to an end 114 of the extension 108 for driving the piston 104. The driving unit 112 drives the piston 104 to move in a to and fro manner within the cavity 102. In an embodiment the driving unit 112 may rotate the piston 104 and simultaneously move it in a to and fro manner. When the piston 104 moves, a first chamber 116 and a second chamber 118 are formed within the cavity 102.
The cavity 102 may have one or more inlet check valves and one or more outlet check valves. For example the cavity 102 may have an inlet check valve 120, an inlet check valve 122, an outlet check valve 124 and an outlet check valve 126. While the piston 104 moves within the cavity 102 a solution flows into and out of the cavity 102 through these check valves. The inlet check valves 120 and 122 are capable of receiving the solution into the cavity 102 shown by arrows 128 and 130. Further the outlet check valves 124 and 126 are capable of supplying the solution from the cavity 102 shown by the arrows 132 and 134. The inlet check valves 120 and 122 are configured at opposite orientation as compared to the outlet check valves 124 and 126. For instance the cavity 102 may have the inlet check valves 120 and 122 arranged at one side of the cavity 102 as illustrated in FIG. 1. Whereas the outlet check valves 124 and 126 are configured at another side i.e. an opposite side of the cavity 102 as compared to the inlet check valves 120 and 122.
During operation the piston 104 may move from the second chamber 118 to the first chamber 116 so that volume in the second chamber 118 increases and volume in the first chamber 116 decreases as illustrated in FIG. 2. When the piston 104 moves towards the first chamber 116 a suction pressure is created within the second chamber 118 and an expelling pressure is created in the first chamber 116. In an embodiment sealing such as sealing 136 may be provided in the cavity 102 so that solution from these chambers does not leak between the chambers i.e. the first chamber 116 and the second chamber 118. The sealing 136 may be arranged at a substantial middle portion of the cavity 102. In another embodiment the sealing 136 may be configured to move along with the piston 104 within the cavity 102. It may be noted that the circular or ring shaped seal 136 is merely exemplary and hence seals may have other structural configuration and dimension. Consequently the solution enters through the inlet check valve 122 into the second chamber 118 and the solution present in the first chamber 116 passes out through the outlet check valve 124. The inlet check valve 122 and the outlet check valve 124 may be arranged in opposite sides of the cavity 102. In an embodiment the inlet check valve 122 and the outlet check valve 124 may be arranged in a diagonally opposite manner along the sides of the cavity 102 as illustrated in FIG. 3. The inlet check valve 122 and the outlet check valve 124 may be in a closed position. In an embodiment each of the outlet check valve 124 and the inlet check valve 120 may be configured to close and open for allowing the solution to flow in and flow out of these pumps. The outlet check valve 124 and the inlet check valve 122 may be in a closed position. In other embodiments the inlet check valve 120 and the outlet check valve 124 may be configured in any other manner for allowing the solution to flow in and out of the cavity 102.
FIG. 3 illustrates the movement of the piston 104 from the second chamber 118 to the first chamber 116 according to an embodiment. During movement of the piston 104 volume in the second chamber 118 increases and volume in the first chamber 116 decreases as illustrated in FIG. 3. According to an embodiment the volume formed in the first chamber 116 and the volume formed in the second chamber 118 are the same. At this stage the second chamber 118 may be filled with the solution as explained in conjunction with FIG. 2. When the piston 104 moves towards the second chamber 118 a suction pressure is created in the first chamber thereby enabling a solution to flow into the first chamber 116 through the inlet check valve 120. Further the solution in the second chamber 118 is supplied out through the outlet check valve 126 from the cavity 102. The inlet check valve 122 and the outlet check valve 124 may be in a closed position.
FIG. 4 illustrates the piston 104 connected to the driving unit 112 and a resilient unit 402 according to an exemplary embodiment. The piston 104 is operated by the driving unit 112. The driving unit 112 is connected to an end 114 of the extension 108. The driving unit 112 moves the piston 104 to move from the first chamber 116 to the second chamber 118. At this stage as explained in conjunction with FIG. 3 the solution is received within the first chamber 116 through the inlet check valve 120. Further the solution in the second chamber 118 is supplied or expelled out through the outlet check valve 124. Now the piston 104 moves from the second chamber 118 to the first chamber 116 with the help of the resilient unit 402. In an embodiment the resilient unit 402 may include a piston head connected to a spring arrangement. The piston head may be an end 404 of the extension 110 which is connected to the resilient unit 402. The end 404 of the extension 110 may be an open end where the resilient unit 402 is connected. The driving unit 112 may have the power to compress the spring arrangement for moving the piston 104. Similarly the spring arrangement may have the strength to expand to move the piston 104 to suck liquid through the inlet check valve 122 and to press the liquid through the outlet check valves 124. In an embodiment the spring arrangement may be a coil spring that connects to the end 404. In another embodiment the spring arrangement may be connected to other end of the piston 104 if the piston 104 has a flange where it is connected to a driving unit. The spring arrangement compresses when the piston 104 moves from the first chamber 116 to the second chamber 118. The spring arrangement decompresses or expands to move the piston 104 to move from the second chamber 118 to the first chamber 116. During the movement the solution in the first chamber 116 is pumped out and solution is sucked into the second chamber 118. The spring arrangement may be configured to move the piston 104 at the same speed and magnitude equivalent to the speed and magnitude associated with movement of the piston 104 driven by the driving unit 112. The spring arrangement may be a helical spring or any other spring arrangement configured to facilitate the movement of the piston 104.
In an embodiment the spring arrangement may be in a fixed position and thus it compresses and expands to facilitate the movement of the piston 104. The spring arrangement may be removably coupled to the end 404 of the piston 104. For instance the spring arrangement may be coiled around the end 404. Even though only one spring arrangement is present connected to the end 404. However it may be envisioned that the multiple springs can be engaged with the end 404 for moving back the piston 104 after being driven by the driving unit 112. The spring arrangement described as the resilient unit 402 is according to an exemplary embodiment and hence it may be noted that the resilient unit 402 can be any mechanical or electromechanical or pneumatic arrangement that can act as a resilient unit to facilitate the to and fro motion of the piston 104 within the cavity 102.
Now moving on to FIG. 5 illustrating a pump system 500 having a piston 104 operated by a driving unit 502 according to an exemplary embodiment. The driving unit 502 may be an eccentric drive unit. The end 114 of the extension 108 is connected to the driving unit 502 and the other end 404 may be connected to a resilient unit 402. The resilient unit 402 may be but not limited to a spring arrangement. The driving unit 502 connected to the end 114 is configured to move the piston 104 from the first chamber 116 to the second chamber 118. As shown in FIG. 5 the driving unit 502 is configured to rotate in an anti-clockwise direction for moving the piston 104 from the second chamber 118 to the first chamber 116. . The pulsations from the total flow out from the two chambers is held as low as possible by varying the motor speed during the stroke. For this eccentric design the lowest pulsations may be achieved by having a substantially higher motor speed at the piston end positions than in the middle of the stroke. The pulsating force may be unbalanced shaking forces that can affect the movement of the piston 104. Such pulsating forces may be generated in case to and fro movements of the piston 104 are not in the same speed and magnitude. Due to driving the piston 104 at higher speed, to and fro movement of the piston 104 may be made uniform i.e. the volume developed in the first chamber 116 and the volume formed in the second chamber 118 may become same. Consequently the amount of solution received within the first chamber 116 and the amount of solution received within the second chamber 118 are equal. Moreover the flow rate of the solution moving out of the outlet pump 124 and the outlet pump 126 may be the same due to adjusting the speed and magnitude of operation of the driving unit 112.
In an alternate embodiment the driving unit 502 may be a cam unit. In this case the movement of the piston 104 may be adjusted based on a cam profile of the driving unit 502. The cam profile may have multiple profiles that can facilitate the movement of the piston 104. It may be noted that the driving unit 502 may have different structural and functional configuration for facilitating the movement of the piston 104 without limiting from the scope of the disclosure.
Moving now to FIG. 6 illustrating a pump system 600 having a piston 602 operated by a driving unit 604 according to an exemplary embodiment. The piston 602 in this embodiment may have only one extension such as an extension 606. The piston 602 may also have an enlargement 608 with a larger dimension as compared to the extension 606. An end 610 of the extension 606 is driven by the driving unit 604. The driving unit 604 may be a driving unit that can operate the piston 602. The piston 602 moves from the second chamber 118 to the first chamber 116 in response to be driven by the driving unit 604. The enlargement 608 gets positioned in the second chamber 118. Here the solution in the first chamber 116 is expelled out and solution is received into the second chamber 118. Thereafter the piston 602 moves from the first chamber 116 to the second chamber 118 in response to being pulled by the driving unit 604. Here the enlargement 608 moves into the second chamber 118. In this stage the solution in the second chamber 118 is expelled out and solution is received into the first chamber 116. In FIG. 6, it may be noted that the two pump chambers (i.e. the first chamber 116 and the second chamber 118) may not have equal volume pumped per mm piston stroke by the piston 602. In such a scenario the driving unit 604 is configured to vary its motor speed so that speed of movement of the piston 602 can be varied. Thus change in volume of the chambers may be compensated by having a higher motor speed when a chamber with the smaller pump effect is delivering the solution. However the inlet flow to the pump in this case may not be stable but that may not be significant.
FIG. 7 illustrates an inline conditioning system 700 according to an exemplary embodiment. The inline conditioning system 700 includes the pump system 100 including the cavity 102 within which the piston 104 moves to and fro. The piston 104 may have an enlargement at a substantial middle portion. In an embodiment the piston 104 may have a middle portion 106 with a larger dimension and extensions 108 and 110 provided at both sides of the middle portion 106. The extensions 108 and 110 may have a smaller dimension as compared to the middle portion 106. The piston 104 may be connected to an end by the driving unit 112 for driving the piston 104. More specifically the driving unit 112 is connected to the end 114 of the extension 108 for driving the piston 104. The driving unit 112 drives the piston 104 to move in a to and fro manner within the cavity 102. When the piston 104 moves, a first chamber 116 and a second chamber 118 are formed within the cavity 102. The piston 104 during it's to and fro motion moves from the first chamber 116 to the second chamber 118. This is explained in detail in conjunction with FIG. 1.
The cavity 102 may have one or more inlet check valve and one or more outlet check valve. For example the cavity 102 may have an inlet check valve 120, an inlet check valve 122, an outlet check valve 124 and an outlet check valve 124. While the piston 104 moves within the cavity 102 a solution flows into and out of the cavity 102 through these check valves. The inlet check valves 120 and 122 are capable of receiving the solution into the cavity 102 shown by arrows 128 and 130. The inlet check valves 120 and 122 are connected to a container 702 and a container 704. 0020Further the outlet check valves 124 and 126 are capable of supplying the solution from the cavity 102 shown by the arrows 132 and 134. The outlet check valves 124 and 126 are connected to the buffer preparation unit 706. The solutions supplied through the outlet check valves 124 and 126 are supplied to the buffer preparation unit 706. The buffer preparation unit 706 receives the solutions to prepare the desired buffer solution. Based on the required buffer solution the solutions supplied by the pump system 100 can be varied. It may be noted that the inline conditioning system 700 described herein with respect to FIG. 7 is shown to include few functional units but it may include multiple other functional units that facilitates in inline conditioning without limiting from the scope of this disclosure.
From the foregoing, it will be appreciated that the above pump system is that it has multiple check valves that can be driven by a single motor each for supplying solutions. In this pump system a single piston is configured to operate the flowing in of the solutions through inlet check valves and flowing out of the solutions through outlet check valves. The piston may be operated by one motor which renders the pump system to be simple in construction and operable with ease. Further in an inline conditioning application in chromatography the pump system facilitates efficient inline dilution and purification of proteins. Further the number of driving units used here is less as compared to current systems and driven using single piston and motor. These pump systems provided herein is free of any pulsating forces as compared to current systems having multiple pumps which is affected by pulsating forces. The pump system provided has uniform flow rate accuracy that facilitates in efficient inline dilution or conditioning in a chromatography system. The pump system is also simple in construction and cost efficient.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any computing system or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.

Claims

We claim:

1. An inline conditioning system comprising:

a pump system comprising:

a cavity comprising at least one inlet check valve and at least one outlet check valve; and

a piston having an enlargement at a substantially middle portion of the piston, wherein the piston is capable of moving within the cavity for forming a first chamber and a second chamber and receiving a solution within the cavity, wherein upon movement of the piston the volume in the first chamber is increased and simultaneously the volume in the second chamber is decreased and vice versa.

2. The inline conditioning system of claim 1, wherein the piston have a first extension and a second extension at opposite ends of the enlargement, the first extension and the second extension having smaller configuration compared to the enlargement.

3. The inline conditioning system of claim 2 further comprising:

a driving unit connected to the first extension for moving the piston; and

a resilient unit connected to the second extension for retrieving the position of the piston.

4. The inline conditioning system of claim 1, wherein the piston having an extension at an end of the enlargement, the extension having smaller configuration compared to the enlargement, the inline conditioning system comprising a driving unit connected to the extension for moving the piston.

5. The inline conditioning system of claim 1, wherein movement of the piston facilitates receiving a solution within the cavity through an inlet check valve and supplying the solution outside the cavity through an outlet check valve.

6. The inline conditioning system of claim 1, wherein when the solution is used for inline conditioning in a chromatography system, the solution is one of acid, base, salt and buffer.

7. The inline conditioning system of claim 1, wherein an inlet check valve of the at least one inlet check valve is configured at opposite orientation as compared to the orientation of an outlet check valve of the at least one outlet check valve.

8. The inline conditioning system of claim 1, wherein upon moving the piston from the first chamber to the second chamber the solution is received within the first chamber through an inlet check valve configured at the first chamber and the solution is supplied out from the second chamber through an outlet check valve configured at the second chamber.

9. The inline conditioning system of claim 8, wherein upon moving the piston from the second chamber to the first chamber the solution is received within the second chamber through an inlet check valve configured at the second chamber and the solution is supplied out from the first chamber through an outlet check valve configured at the first chamber.

10. The inline conditioning system of claim 1, wherein the piston having an extension at the enlargement, the inline conditioning system comprising a driving unit connected to an end of the extension for moving the piston, wherein the driving unit is configured to vary the motor speed for varying the speed of movement of the piston.

11. The inline conditioning system of claim 1, wherein a buffer preparation unit or a mixer is connected to the pump system for receiving the solution for buffer preparation.