WO2016083895A1

WO2016083895A1 - Assembly for agitating or mixing material

Info

Publication number: WO2016083895A1
Application number: PCT/IB2015/002390
Authority: WO
Inventors: Alf Löfving; Håkan Samuelsson; Lennart Myhrberg; Sten Johansson
Original assignee: Alf Löfving; Håkan Samuelsson; Lennart Myhrberg; Sten Johansson
Priority date: 2014-11-26
Filing date: 2015-11-24
Publication date: 2016-06-02
Also published as: TW201632254A

Abstract

An assembly (100) for agitating or mixing material. The assembly (100) includes a flexible bag (110, 1) having a wall and defining an interior for containing the material. The assembly (100) also includes a rigid carrier (120) disposed on an exterior of the bag (110) and a bearing (132) disposed on the interior of the bag (110) adjacent to the carrier (120). The assembly (100) also includes a mixing element (130, 134) disposed on the interior of the bag (110) and rotatably supported on the bearing (132). The assembly (100) further includes a motor drive unit (140) disposed on the exterior of the bag (110) adjacent to the carrier (120) for rotating the mixing element (130, 134). In some aspects the mixing element (130, 134) and motor drive unit (140) may include magnets (136, 138, 139, 144, 146) configured to align the mixing element (130, 134) and motor drive unit (140) as a result of application of an external magnetic field.

Description

ASSEMBLY FOR AGITATING OR MIXING MATERIAL

Description

[0001] This application claims priority to U.S. Provisional Patent Application No. 62/084,896, filed November 26, 2014, the entire contents of which are incorporated herein by reference.

Technical Field

[0002] This disclosure generally relates an assembly for agitating or mixing material and, more particularly, to a flexible bag assembly for agitating or mixing material.

Background

[0003] Pharmaceutical manufacturing is primarily done by mixing material in batches in reusable stainless-steel vessels and similar reusable equipment. One drawback with this type of production is that it requires significant initial investments in materials and equipment, as well as a costly cleaning and sterilization systems and protocols. In some instances, pharmaceutical manufacturing is accomplished through single use technologies. For example, materials are mixed by using equipment (often made from different types of plastics) that are designed for a single use. The equipment may be fabricated, sterilized, and assembled in a clean room environment to provide a production assembly for use as part of a pharmaceutical manufacturing process. After production, the equipment is cleaned and disposed of as waste. Using disposable or single use equipment may result in lower initial investment and a more adaptive manufacturing process.

[0004] One goal in pharmaceutical manufacturing is ensuring the added components, e.g., the pharmaceuticals, drugs, and other materials combined in a formulation, are uniformly blended. This is usually done with a mixer. Different materials and formulations have different requirements and often require different mixing methods. For example, a powder may be brought into liquid solution with or without other materials and with or without aeration. For another example, living cells that are typically sensitive to shear may require mixing and combination with other materials without damage. And other components may need variable mixing, e.g., low shear, high shear, vortex, non-vortex mixing, all in a single batch to provide suitable end results and satisfactory mixing. Additionally, the materials and other substances may be heated or cooled, or include a chemical or biological processing, during the mixing process. Another goal in pharmaceutical manufacturing is timely, efficient, and complete mixing.

Generally, the quicker and more efficient a substance or compound is mixed into homogenous blend, the less time required for the manufacturing process.

[0005] In some mixer arrangements, a drive shaft must be sealed within an opening in the mixing vessel, e.g., within a stainless-steel (multi-use) or flexible bag (single-use) system. In such instances, there is a risk that the seals will contaminate the materials inside the vessel, either by leaching of the seal material itself or by leakage of contaminants into or out of the vessel through the seal. In addition, one or more of the materials within the mixing vessel may be hazardous and there is a risk that the seals will leak hazardous material (e.g., vapors or liquids) out of the vessel and into the surrounding environment. Such exposure may be harmful to workers. Furthermore, after mixing and emptying the mixed components from the vessel, some components may remain lodged cavities that are formed within the seal. These cavities may collect and trap material which may be difficult to clean.

[0006] The disclosed mixing assembly is directed to overcoming one or more of the shortcomings mentioned above and/or other shortcomings in art.

Summary of the Disclosure

[0007] According to one aspect of the disclosure, a flexible bag assembly for mixing a material is disclosed. The assembly comprises a flexible bag having a wall and defining an interior for containing the material. The assembly also includes a rigid carrier disposed on an exterior of the bag and a bearing disposed on the interior of the bag adjacent to the carrier. The assembly also includes a mixing element disposed on the interior of the bag and rotatably supported on the bearing. The assembly further includes a motor drive unit disposed on the exterior of the bag adjacent to the carrier for rotating the mixing element. The bearing and/or mixer and the drive unit include magnets configured to interact with an alternating magnetic field. Additionally, some or all surfaces in contact with the flexible bag may be coated with a silicon, gel, fluid, foam, or other material to protect the bag, for example by reducing frictional forces or preventing the bag from degrading.

Brief Description of the Drawings

[0008] Figure 1 is a schematic diagram of an exemplary assembly for mixing material;

[0009] Figure 1 schematically illustrates an exemplary mixing assembly 100. The assembly 100 includes a flexible bag, e.g., flexible bag 1 10, that may be formed, arranged, and/or adjusted into one or more different shapes or configurations depending on the specific application. As explained in more detail below, the bag 1 10 includes a wall and generally defines an interior and an exterior with respect to the wall. The assembly 100 also includes a rigid carrier 120 disposed on the exterior of the bag and configured to support at least a portion of the bag 1 10. The rigid carrier 120 may include a removable carrier section (not shown). The assembly 100 also includes a mixing element 130 disposed on the interior of the bag 1 10. The mixing element 130 includes a mixer 134 rotatably supported on a bearing element 132. The assembly 100 also includes a drive unit 140 disposed on the exterior of the bag 1 10. The drive unit 140 may be disposed substantially adjacent the mixing element 130.

[0010] The flexible bag 1 10 may be made out of any suitable material. For example, the material may include generally flexible polymers such as polyethylene or polypropylene. The flexible bag 1 10 may include a single layer or a composition of two or more layers. The layers may be suitable to keep various materials including gases, solids or liquids in or out of the bag. The material may be impermeable to particular types or specific gases liquids or solids and the material may be permeable to particular types or specific gases, liquids or solids. The material may be configured to block certain types of light or radiation such as ultraviolet, visible light, infrared light, and/or x-rays.

[001 1 ] In one example, flexible bag 1 10 may include at least three layers, including an inner layer, adjacent to and forming the interior surface of the flexible bag 1 10, that is inert to the materials being mixed inside the flexible bag 1 10, an outer layer, adjacent to and forming the exterior surface of the flexible bag 1 10, and one or more middle layers disposed between the inner and outer layers. The inert inner layer may be formed from a material that helps prevent or reduce contamination of the materials to be mixed or otherwise disposed in the interior of the bag. One or more of the middle layer may be materials that are impermeable to one or more gasses to further prevent or reduce contamination of the materials to be mixed or otherwise disposed in the interior of the bag. For example, the gas impermeable layer may reduce or prevent gases, vapors, or other fluids that are part of or result from mixing the material from escaping the interior of the flexible bag 1 10 and leaking to an exterior environment. In addition, the gas impermeable layer may reduce or prevent gases, vapors, or other fluids present in a surrounding environment from passing through and entering the interior of the flexible bag. The outer layer may be a material that is inert to the conditions outside the flexible bag 1 10. The outer layer may provide a third barrier of protection against contamination of the mixture in the flexible bag 1 10.

[0012] It is contemplated that any of the respective layers may be formed from, for example, polyethelylene, linear low-density polyethylene, polyethylene vinyl acetate, polypropylene, ethylene tetrafuoroethylene, polyvinylidene fluoride, polyethylene terephthalate, polyamide, ethylene vinyl alcohol, styrene ethylene butadiene styrene, polyethylene terephthalate glycol, polyvinylidene fluoride, or other suitable materials. In general, suitable materials for any of the respective layers may be biodegradable, non-biodegradeable, opaque, transparent, translucent, may or may not block ultraviolet light or radiation, may or may not block x-rays, may or may not have insulative properties, may or may not be conductive, and may include any combination of such properties. It is also contemplated that any of the respective layers may be any thickness, and the overall wall of the flexible bag may be any thickness. It is further contemplated that the respective layers may each have the same thickness, may have different thicknesses, and/or one or more layers of the same material may have the same or different thicknesses throughout the wall of the bag.

(0013] It is contemplated that the wall of the flexible bag 1 10 any include any number of layers. For example, the wall of the flexible bag 1 10 may include three layers, e.g., an inner layer, an outer layer, and a single middle layer disposed between the inner and outer layers. In addition, or as an alternative, the wall of the flexible bag 1 10 may include any number of middle layers, e.g., two, three, four, five, or six layers. It is also contemplated that flexible bag 1 10 may include any number of different layers or may include a one or more layers of the same material inter-disposed between other layers. The layers may be configured in any order and include any material, including any of the materials described hereinabove.

[0014] A membrane or piece of material (not shown) may be attached to the interior or the exterior wall of flexible bag 1 10. The membrane may be formed from any type of material, be any suitable shape or contour, have any suitable or desired thickness, and may, or may not, attect the mixing dynamics or me material. In an exemplary embodiment, the additional membrane or material is made of silicone. The membranes may reduce turbulence in flexible bag 1 10 by providing a substantially smooth interior surface by covering surface irregulatarites that may form in the flexible bag wall. A smooth interior may help promote uniform mixing, reduce or eliminate vortices, and/or generally promote laminar flow. It is contemplated that the membrane or piece of material may be sufficiently elastic to stretch and extend so as to accommodate the carrier and/or bearing when assembled without tearing or otherwise breaking. Alternatively, the membrane or piece of material may be configured to tear or otherwise break when the carrier and/or bearing are assembled. By being configured to tear or otherwise break, the membrane may provide a visible indication that the flexible bag has been used and/or that a particular mixing operation has been completed. It is contemplated that the membrane may be attached to the bag 1 10 via any suitable method including, for example, adhesive or welding, and may be attached with a continuous or intermittent attachment joint.

[0015J Rigid carrier 120 may include legs or other supports (not referenced) to support the carrier 120 and overall assembly relative to a surface or other structure. It is contemplated that carrier 120 may not include legs or support structures and may instead include other suitable support means to support the carrier 120 and the overall assembly relative to a table.

[0016J When included, the removable carrier section 122 is a modular component of the rigid carrier 120 that may be removed from the remainder of the rigid carrier 120 and relocated, e.g., placed, at one or more various locations around rigid carrier 120. Rigid carrier 120 may have one, two, three, four, or more locations configured to accommodate the removable carrier section 122. One or more removable carrier section 122 may be used in rigid carrier 120 and may be disposed in one or more locations configured to accommodate the removable carrier sections. The removable carrier section 122 permits the drive unit 140 and the mixing element 130 to be moved to different locations. The removable carrier section 122 may be attached or secured to rigid carrier 120 by any suitable coupling method.

[0017] The drive unit 140 may be attached or secured by any suitable coupling to the carrier 120 and, in particular, to the removable carrier section 122. For example, the drive unit 140 may be coupled to the carrier 120 and/or the carrier section 122 by one or more brackets, and/or one or more locks, and/or one or more fasteners, e.g., bolts, screws, rivets, and/or one or more clamps, and/or any other suitable coupling. The coupling is constructed and/or arranged to permit adjustability in the location of the drive unit 140 relative to the carrier 120 and/or the bag 1 10 and/or the mixing element, as well as permit adjustability of the angle and/or orientation of the drive unit 140 relative to the carrier 120, and/or the bag 1 10, and/or the mixing element 130. For example, a drive shaft of the drive unit 140 may be oriented substantially perpendicular, e.g., approximately 90°, to the wall of rigid carrier 120 and/or flexible bag 1 10. Or the drive shaft of the drive unit 140 may be orientated at a non-perpendicular angle, e.g., approximately 89°, 88°, 87°, 86°, 85°, 80°, 75°, 60°, 50°, 45°, 40°, 35°, 30°, 25°, 20°, 15°, 10°, 5°, 4°, 3° ,2°, 1 °, or any other suitable angle. It is contemplated that the drive shaft of the drive unit 140 may be at any angle between 0" and 90" and that the drive shaft ot the drive unit 1 4U and/or the drive unit 14U may be adjusted or varied to any angle before, during, and/or after mixing.

[0018| As described in more detail below, different angles of the drive unit 140 and/or the drive shaft allow for variable and different mixing dynamics for the materials inside the flexible bag 1 10 before, during and/or after mixing of materials. In particular, the angle of the drive unit 140 and/or the drive shaft may be varied during active mixing of materials, e.g., when the drive unit 140 is actively driving the mixer 134, to dynamically vary the mixing characteristics of the materials. An exemplary sequence of mixing may include starting with the mixing element substantially perpendicular, changing the angle of the drive unit 140 and mixing element 134 to approximately 75°, and changing the angle of the drive unit 140 and mixing element 134 to substantially perpendicular.

[0019] The mixing element 130 may be disposed on an interior of the flexible bag 1 10 and may be any type of mixer suitable for mixing, agitating, or stirring material inside the flexible bag 1 10. In an exemplary embodiment, the mixing element 130 includes mixer 134 with four blades. It is contemplated, however, that the mixer 134 may include any number of blades in any arrangement. The mixer is rotatably supported on the bearing 132 and driven by rotor 141 of the drive unit 140 to agitate, mix, or stir the material. The mixer 134 may be supported on the bearing 132 in any suitable manner. For example, the bearing 132 may include a snug-fit connection with the mixer 134 such that an internal surface of the mixer 1 34 is in sliding relationship with an external surface of the bearing 132.

[0020] Bearing 132 may include magnetically attractive material or magnet 136. Magnetically attractive material or magnet 136 may be disposed within or on the exterior of bearing 132. It is contemplated that a plurality of magnets may be positioned on and/or within bearing 132. Such a plurality may include any number of elements or magnets, e.g., two, three, four, five, or more, and may include elements or magnets arranged in any pattern.

[0021] Mixer 134 also includes magnets 138 and 139. Magnets 138 and 139 may be disposed on the exterior of mixer 134 or may be included within mixer 134. It is contemplated that a plurality of magnets may be positioned on and/or within mixer 134. Such a plurality may include any number of magnets, e.g., two, three, four, five, or more, and may include magnets arranged in any pattern.

[0022] Drive unit 140 may be disposed on the exterior of the flexible bag 1 10 and adjacent the rigid carrier 120. The drive unit 140 may include a rotor 141 and a stationary drive shaft 142 (or stator) and may be configured to position the bearing 132 and rotate, e.g., the drive, mixer 134. For example, the drive unit 140 may be configured for contactless transfer of rotational movement from the rotor 141 outside the bag 1 10 to the mixer 134 as the mixer 134 is supported on the bearing 132 inside the bag 1 10. Drive shaft 142 can be located first in position to hold bearing 132 in place and rotor 141 can be slid over bearing 132 in a two-step process to align rotor 141 with mixer 134. One or more magnets 146 and 148 are disposed in or on the rotor 141. One or more magnets, 144, are disposed in or on the drive shaft 142. Any or some of the magnets 146, 148, 144 on the rotor 141 and/or the drive shaft 142 may be permanent magnets or may be electro-magnets. |UU2.J] The rotor 14 1 is capable ot being rotated relative to drive shatt 14 . Magnets i j», I jy, 144,

146, and 148 may be configured such that when the drive shaft 142 is positioned adjacent bearing 132 and the rotor 141 is positioned adjacent the mixer 134 and rotatably and/or axially moved (e.g., in directions

200, 210, and/or 220) the resulting external magnetic field realigns the magnetic fields of magnets 138,

139, 144, 146, and 148. The realignment of the magnetic fields of magnets 138, 139, 144, 146, and 148 causes an attractive force between magnets 136 and 144 and between magnets 138 and 146 and between magnets 139 and 148. For example, the alignment of magnetically attractive material or magnet 136 and magnet 144 align, position, and hold bearing 132 relatively stationary with respect to the drive shaft 142 and the bag 1 10. Additionally, the alignment of magnets 138 and 146, and 136 and 144 aligns the rotor

141 and bearing 132. The alignment of drive shaft 142 and bearing 132 and the attractive force between magnets 138, 139 on the mixer 134 and the magnets 146, 148 on the rotor 141 causes the motion of rotor

141 to be transferred to mixer 134. Drive shaft 142 and mixer 132 rotate about the axis defined by the attractive force between magnets 136 and 144. The rotational axis may be oriented at any angle relative to the flexible bag 1 10, and may be dynamically changed and adjusted during mixing.

[0024] Magnets 138 and 139 may also exert magnet force on one another. Magnet 144 exerts an upwardly directed force on magnets 138 and 139 (indirectly directing a force on mixer 134). Magnets 138 and 139 generate a magnetic force exerting a downwardly directed force on bearing 132. It is contemplated that the mixer 134 may be completely or partially magnetically supported on the bearing 132. For example, the magnitude and direction of the magnetic forces may be configured and/or dynamically adjusted to provide or modify the degree to which the mixer 134 is magnetically supported or directly supported by the bearing 132. It is contemplated that the mixer 134 may be completely magnetically supported, completely directly supported, or supported both magnetically and directly according to any relative percentage of support.

[0025] Further, drive unit 140 may include a non-rotating drive shaft having a plurality of separate electrical coils mounted therein that can be alternatively and sequentially electrified to produce a moving, e.g., revolving, magnetic field to magnetically support and rotate a mixer. It is contemplated that in such an arrangement, the mixer and/or the bearing may or may not have a series of magnets formed therein configured to interact with the alternating magnetic field produced by the non-rotating drive shaft of the drive unit.

[0026] It is contemplated that any number of the features described above with respect to a particular embodiment may be combined with one or more of the features described with respect to the other embodiments, and/or combined in any suitable arrangement in additional embodiments.

[0027] It will be apparent to those skilled in the art that various modifications and variations can be made to assembly of the present disclosure. Other embodiments will be apparent to those skilled in the art from consideration of the specification and practice of the flexible bag assembly for mixing disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope being indicated by the following claims and their equivalents.

Claims

Claims What is claimed is:

1. An assembly for agitating a material, comprising:

a flexible bag having a wall and defining an interior for containing the material;

a rigid carrier disposed on an exterior of the bag;

a bearing disposed on the interior of the bag adjacent the carrier;

a mixing element disposed on the interior of the bag and rotatably supported on the bearing; and a motor drive element disposed on the exterior of the bag adjacent the carrier for rotating the mixing element.