The disclosure relates generally to mixing, and more particularly, to a high volume mixing of a slurry such as a ceramic suspension with reduced cooling of the suspension.
Conventional manufacture of ceramic components includes mixing constituents to form a ceramic suspension during which the temperature of the suspension is carefully controlled to ensure a high quality ceramic and prevent premature curing. In particular, the mixing of ceramic suspension constituents typically creates high temperatures such that a ceramic suspension must be cooled, e.g., to −40° C., during mixing to prevent premature curing and to allow for the necessary intermixing of the constituents. Where high volumes of the ceramic suspension are needed, the process can be very complicated including, for example, pre-chilling the constituents and then repeatedly mixing certain constituents, chilling the suspension, adding additional constituent(s), and re-chilling the suspension, before using the suspension to form the ceramic component. The process is very time consuming because of the need to keep the suspension cool. An additional challenge is attaining a high quality intermixing of constituents as the process proceeds. Current mixers for suspension are rudimentary, providing an overhead mixer to an open-air bowl and using a simple planetary path for the mixing head. Use of such mixers can cause defects by pulling in air into the suspension which creates additional steps to remove the air. Current mixers also present challenges during the above-described mixing process, e.g., keeping the suspension cool and handling the suspension between mixing and chilling steps. Consequently, current mixers do not provide effective mixing with low heat and quick production for high volumes.
A first aspect of the disclosure provides a mixer, comprising: a sealed mixing chamber having an interior; a rotating mixing bowl within the interior of the sealed mixing chamber; a stand for operatively supporting the sealed mixing chamber, the stand including: a foundation, a mixing chamber base movably coupled to the foundation and positioning the sealed mixing chamber at an angle relative to horizontal, and a linear actuator system configured to move the mixing chamber base relative to the foundation in at least one linear direction; and a rotating mixing head operatively positioned and sealingly disposed within the sealed mixing chamber, the rotating mixing head rotating within the rotating mixing bowl.
A second aspect of the disclosure provides a method of mixing a ceramic suspension with reduced cooling to the ceramic suspension, the method comprising: adding at least two constituents of the ceramic suspension into a mixing bowl positioned in a mixing chamber, the mixing chamber and the mixing bowl being tilted relative to horizontal; sealing the mixing chamber and applying a vacuum, creating a sealed mixing chamber; and mixing the at least two constituents in the mixing bowl in the sealed mixing chamber with reduced cooling by simultaneously: first rotating a rotating mixing head relative to the mixing bowl, second rotating the mixing bowl, and moving the sealed mixing chamber in at least one linear direction.
A third aspect of the disclosure provides a mixer for mixing a ceramic suspension with reduced cooling the ceramic suspension, the mixer comprising: a sealed mixing chamber having an interior and an exterior; a rotating mixing bowl within the interior of the sealed mixing chamber, the rotating mixing bowl including a first rotational actuator; a stand for operatively supporting the sealed mixing chamber, the stand including: a foundation, a mixing chamber base movably coupled to the foundation by a plurality of elastic mounts, the mixing chamber base positioning the sealed mixing chamber at an angle relative to horizontal, and a linear actuator system to move the mixing chamber base relative to the foundation, the linear actuator system including: a first linear actuator system coupled to the mixing chamber base for moving the sealed mixing chamber in a first linear direction; and a second linear actuator system coupled to the mixing chamber base for moving the sealed mixing chamber in a second linear direction different than the first linear direction; and a rotating mixing head operatively positioned and sealingly disposed within the sealed mixing chamber, the rotating mixing head including a second rotational actuator for rotating the rotating mixing head within the rotating mixing bowl.
The illustrative aspects of the present disclosure are designed to solve the problems herein described and/or other problems not discussed.
These and other features of this disclosure will be more readily understood from the following detailed description of the various aspects of the disclosure taken in conjunction with the accompanying drawings that depict various embodiments of the disclosure, in which:
It is noted that the drawings of the disclosure are not to scale. The drawings are intended to depict only typical aspects of the disclosure, and therefore should not be considered as limiting the scope of the disclosure. In the drawings, like numbering represents like elements between the drawings.
Embodiments of the disclosure provide a mixer and a method for mixing materials such as constituents of a ceramic suspension with at least reduced cooling of the suspension. As will be described, the mixer provides at least four motions that collectively act to mix the ceramic suspension with reduced friction and thus at least reduces, and possibly eliminates, the need to cool the ceramic suspension. The ceramic suspension may include any now known or later developed ceramic suspension such as but not limited to those for creating ceramic cores for metal castings of gas turbine blades. While embodiments of the disclosure will be described for applications with ceramic suspension, it is emphasized that the teachings of the disclosure are applicable to any material requiring mixing.
As shown in the schematic top view of
Returning to
Mixer 100 may also include a rotating mixing bowl 140 within interior 104 of sealed mixing chamber. Constituents to be mixed are held by rotating mixing bowl 140 within sealed mixing chamber 102. Rotating mixing bowl 140 may include any industrial strength material of appropriate strength and corrosion resistance to accommodate materials to be mixed therein. Materials may include but are not limited to: stainless steel and aluminum. Rotating mixing bowl 140 may also include a rotational actuator 142 positioned in exterior 106 of sealed mixing chamber 102 for rotating mixing bowl 140. Rotational actuator 142 may include any now known or later developed source of rotation such as but not limited to an electric, hydraulic or pneumatic motor or some form of engine. Rotational actuator 142 may extend into sealed mixing chamber 102 using any now known or later developed ferrofluidic seal or seal bearing 144. Rotating mixing bowl 140 may removably couple to rotational actuator 142 within sealed mixing chamber 102 in any fashion. In one example, shown in the perspective view of
Mixer 100 may also include a stand 150 for operatively supporting sealed mixing chamber 102. As will be described, stand 150 includes a number of features that allow for multiple axis rotation and linear movement of sealed mixing chamber 102 that allows for mixing of a ceramic suspension with at least reduced cooling of the suspension.
Stand 150 may include a foundation 152 for supporting sealed mixing chamber 102 relative to a floor or other foundational base 154. Stand 150 may also include a mixing chamber base 160 movably coupled to foundation 152 and positioning sealed mixing chamber 102 at an angle β relative to horizontal. As shown in
In one embodiment, mixing chamber base 160 may include a first member 164 coupled to a second, angling member 166. First member 164 may include a flat plate configured to mount generally horizontally using elastic mounts 162 to foundation 152, while second, angling member 166 may include a plate or block higher at one side than another to provide an angled upper surface 168 upon which sealed mixing chamber 102 can be mounted. Angle β can be any angle sufficient to cause movement of constituents in rotating mixing bowl 140 from one side of rotating mixing bowl 140 to the other to increase mixing thereof. While angle I is shown as a fixed angle, in an alternative embodiment, second, angled member 166 may be adjustably angled relative to horizontal using, for example, any now known or later developed adjustably hinged member. Sealed mixing chamber 102 may be coupled to mixing chamber base 160 using any now known or later developed couplings, e.g., threaded fasteners, etc.
Rotational actuator 142 for rotating mixing bowl 140 may be positioned within second, angled member 166, but this is not necessary in all cases. In one embodiment, rotational actuator 134 of rotating mixing head 126 and rotational actuator 142 cause rotation in opposite directions. In this fashion, improved mixing compared to just use of rotating mixing head 126 is observed. The use of angle β also adds to the improved mixing as it causes the suspension to move towards one side of rotating mixing bowl 140 and intersect rotating mixing head 126 more frequently than if chamber 102 was horizontal.
Stand 150 also includes a linear actuator system 170 configured to move sealed mixing chamber 102 (and rotating mixing bowl 140) in at least one linear direction, e.g., X and/or Y (
Mixer 100 may be employed to mix a ceramic suspension using a method of mixing according to embodiments of the disclosure. The method may include adding at least two constituents of the ceramic suspension into the mixing chamber, i.e., bowl 140. At this stage, mixing chamber 102 may be unsealed. As shown in
Constituents may be mixed in sealed mixing chamber 102 with reduced cooling by simultaneously: rotating mixing head 126 relative to rotating mixing bowl 140 in sealed mixing chamber 102 with rotational actuator 134, rotating the rotating mixing bowl 140 with rotational actuator 142, and moving sealed mixing chamber 102 (and rotating mixing bowl 140) in at least one linear direction (X and/or Y (
Mixer 100 provides technical effect by introducing a mixing technology that creates significantly less heat to the process of mixing ceramic suspensions. With the reduction of heat, it is possible to process larger batches of ceramic suspension immediately, rather than having long cooling steps. Mixer 100 also provides a significant reduction in labor as the material can be processed immediately rather than using a number of mixers that requires long periods of chilling between uses due to temperature constraints. The stand described herein incorporates provides at least four motions which significantly improves mixing quality and reduces mixing time. All of the operational parameters of mixer 100 can be adjusted in a controlled manner, e.g., rotational speeds, linear motion, tilt angle, etc., to accommodate different materials. In addition, the depth of the mixing bowl and/or sealed mixing chamber 102 can also be selected to maximize mixing efficiency.
It should be noted that in some alternative implementations, the steps noted herein may occur out of the order noted or, for example, may in fact be executed substantially concurrently or in the reverse order, depending upon the act involved.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. “Optional” or “optionally” means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where the event occurs and instances where it does not.
Approximating language, as used herein throughout the specification and claims, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as “about,” “approximately” and “substantially,” are not to be limited to the precise value specified. In at least some instances, the approximating language may correspond to the precision of an instrument for measuring the value. Here and throughout the specification and claims, range limitations may be combined and/or interchanged, such ranges are identified and include all the sub-ranges contained therein unless context or language indicates otherwise. “Approximately” as applied to a particular value of a range applies to both values, and unless otherwise dependent on the precision of the instrument measuring the value, may indicate +/−10% of the stated value(s).
The corresponding structures, materials, acts, and equivalents of all means or step plus function elements in the claims below are intended to include any structure, material, or act for performing the function in combination with other claimed elements as specifically claimed. The description of the present disclosure has been presented for purposes of illustration and description, but is not intended to be exhaustive or limited to the disclosure in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the disclosure. The embodiment was chosen and described in order to best explain the principles of the disclosure and the practical application, and to enable others of ordinary skill in the art to understand the disclosure for various embodiments with various modifications as are suited to the particular use contemplated.