Patent Application
20180288831
A very common laboratory operation is heating a round-bottomed flask or other round-bottomed vessel. Flasks can be heated with a flame from a burner but this is very hazardous when associated with flammable solvents often found in laboratories. Steam baths are safer but require a source of steam and this method is otherwise usually not favored due to complications from liquid water present in steam lines, the need to drain condensate water from the bath and temperature control limitations.
Most commonly today, round-bottomed vessels are heated either with heating mantles or with a fluid-filled baths placed on electrical heat sources such as hotplates. Heating mantles are typically constructed from woven-glass-fiber fabric and from glass wool stuffing enclosing a resistance wire or other heating element. Usually the heating mantle is constructed to form a rounded pocket and sized to closely fit the contours of a flask of a certain capacity such as 100 ml, 500 mL, 1 L, 20 L, etc. Consequently, a different heating mantle is required for each size of flask which will likely be heated in the course of laboratory operations and thus an investment in a number of heating mantles is often required. In addition, typically required is a voltage regulating device such as a variable transformer in order to regulate the heat output of the heating mantle. Adjusting such a device to the proper voltage output to achieve a steady temperature is often a matter of trial-and-error. To automatically maintain a temperature set-point may require an additional, separate piece of equipment. To magnetically stir the contents of the round-bottomed flask requires a rotating-magnet device placed under the heating mantle and a magnetic follower in the vessel. However, even with such an arrangement of rotating-magnet device, heating mantle and magnetic follower, satisfactory stirring can fail as the thickness of the heating mantle will separate the rotating magnet from the magnetic follower to the extent that interaction and synchronization of the two magnets is poor.
A fluid-filled bath set on a hotplate can serve as a medium of heat conduction between a flat heating surface and a round-bottomed vessel placed in the bath. Temperature control is usually simpler than with a heating mantle since hotplates often feature digital temperature controls and a thermocouple probe which may be placed in the fluid-filled bath or in the vessel, itself. The bath may be filled with several types of fluids but silicone oil is preferred since it is non-flammable and can be found in grades which are both high boiling and have high decomposition temperatures. The negative aspects of using an oil bath include the following: spillage, the need to adjust of the bath oil level for the displacement of different sized vessels and the need to adjust fluid levels for optimal magnetic stirring height. Any water contamination of the oil will cause oil spattering when the bath is later heated above the boiling point of water. Spillage can occur due to moving and storage of liquid-filled vessels, tipping of fluid-filled baths on jacks or platforms, overflowing due to the thermal expansion of the liquid, cracking or breaking of glass baths and so forth.
Aluminum blocks are found which are formed with both bowl-shaped cavities to receive rounded vessels and with flat bottoms to sit flat on a hotplate. Like heating mantles these aluminum heating blocks are specifically sized for each size of vessel and thus a considerable cost is incurred in obtaining several heating blocks for several different sizes of vessels. Devices which integrate heating blocks with hotplate-type controllers are also available and are purportedly able to accommodate up to three sizes of round vessels. But their utility is typically limited to rounded vessels, because, lacking a flat heating surface, they typically cannot be used as a typical hotplate is used.
Consequently a device is needed which will sit on a hot plate device and transmit heat to a round-bottomed vessel or other rounded apparatus. Further it is desirable for such a device to allow magnetic stirring of the contents of the vessel by means of a magnetic follower placed in the flask. Further it is desirable that such a device be easily adaptable to round bottomed vessels of various sizes and that it be relatively inexpensive to manufacture and easy to use.
The present invention is a variant of that disclosed in U.S. patent application Ser. No. 15/246,733, filed Aug. 25, 2016, and of U.S. Provisional Application Ser. No. 62/210,112, filed Aug. 26, 2015, both of which are hereby incorporated in their entirety herein by reference. The present invention may be used in place of the concentric ring construction disclosed therein, and otherwise optionally with the heating and stirring elements disclosed therein.
The present invention may be described as a device to facilitate the heating of rounded vessels and other rounded objects comprising a flexible polymeric support comprising a plurality of nested, concentric hollow cylindrical portions each having respective upper edges and adapted to be arranged and fixed in at least two configurations such that the upper edges of the concentric hollow cylindrical portions accommodate at least two respective bowl-shaped contours. The flexible polymeric support may comprise an upper side adapted to contact a container of one of the at least two bowl-shaped contours and a lower side opposite the upper side, and additionally comprising a container disposed on the lower side of the flexible polymeric support, the container containing a thermally conductive fluid.
In some embodiments, the concentric hollow cylindrical portions may comprise a heat-conducting polymeric material selected from the group consisting of heat-conducting silicone rubbers.
The device may additionally comprise a mechanism for creating a rotating magnetic field for purposes of stirring a vessel containing a magnet and disposed on the contour formed by the concentric hollow cylindrical portions. The device also may additionally comprise a thermometer, thermocouple or other temperature-sensing device and an orifice or adaptation to attach a temperature-sensing device.
The present invention also may be described as a device to facilitate the heating of rounded vessels and other rounded objects comprising a flexible polymeric support comprising a plurality of nested, concentric hollow cylindrical portions each having respective upper edges and adapted to be reversibly moved from a collapsed configuration wherein the upper edges are substantially coplanar to a fixed configuration such that the upper edges of the hollow cylindrical portions accommodate the shape of a bowl-shaped contour. The flexible polymeric support may comprise an upper side adapted to contact a container of the bowl-shaped contour and a lower side opposite the upper side, and additionally comprising a container disposed on the lower side of the flexible polymeric support, the container containing a thermally conductive fluid.
The present invention also may be described as a device to facilitate the heating of rounded vessels and other rounded objects comprising a flexible polymeric support comprising a plurality of nested, concentric hollow cylindrical portions each having respective upper edges and adapted to be reversibly moved between two (or more) deployed configurations such that the upper edges of the hollow cylindrical portions accommodate respectively the shapes of at least two (or more) different bowl-shaped contours. The flexible polymeric support may comprise an upper side adapted to contact a container of one of the at least two (or more) bowl-shaped contours and a lower side opposite the upper side, and additionally comprising a container disposed on the lower side of the flexible polymeric support, the container containing a thermally conductive fluid.
The present invention also may be described as a device to facilitate the heating of rounded vessels and other rounded objects comprising a container presenting a flexible polymeric support surface, the container containing a malleable material selected from the group consisting of liquids, pastes, putties, greases, gums or other fluids, such that the flexible polymeric support surface is sufficiently malleable so as to be adapted for the heating of objects or containers selected from the group consisting of rounded containers and objects and other rounded, regularly-shaped or irregularly-shaped objects and containers.
The flexible polymeric support surface of this embodiment may comprise a thermal interface silicone rubber selected from the group consisting of silicone rubber compositions and fluoro-silicone rubber compositions containing substantially-uniform dispersions of filler particles chosen from thermally-conducting metals, minerals, ceramics or other inorganic or organic materials.
The malleable material of this embodiment may be selected from the group consisting of high-temperature-resistant thermal-transfer fluids (e.g., such as Paratherm (Paratherm Corp.), Dowtherm (Dow Chemical Corporation), and Therminol (Eastman Chemical Co.); silicone oil thermal transfer fluids (e.g., such as Syltherm XLT HTF, Syltherm 800 Stabilized HTF, Syltherm HF HTF, (all commercially available from Dow Chemical Company)) and silicone fluids, silicone greases and other silicone materials containing a substantially-uniform dispersion of substantially thermally-conducting filler particles such as those selected from particles of heat-conducting metals, mineral particles, ceramic particles, and inorganic or organic materials.
This embodiment of the device may constructed so to form an object or article which is substantially flat on one face and which is, on the opposite face, substantially shaped to form a pocket, socket, depression or basin such as may conform to the profile of a round-bottomed vessel or to the shape of some other rounded or regularly or irregularly shaped object situated or nested in the pocket.
This embodiment of the device may constructed so to comprise concentric circular pleats or folds in the skin of the flexible polymeric support surface such that a pocket of a certain size and shape is formed as a result of one or more of the pleats/folds being substantially tightly folded-in on itself simultaneous with one or more of the other pleats/folds being substantially unfolded; the device thereby being transformable from accommodating a round-bottomed flask of one capacity to then being reversibly transformed to accommodate a round-bottomed flask of a different capacity. In some embodiments, the flexible pleats or flutes or foldable bands in its skin such that in transforming the device to accommodate round-bottomed flasks of differing capacities the total volume of the device shall remain substantially unchanged even as, simultaneously, the height and diameter/width of the device or article may be changed.
In some embodiments, the device may be transformable to accommodate round-bottomed flasks of two, three or four different capacities. For instance, the device may comprise five concentric pleats or folds in one face such that a single device is transformable to accommodate a 100 mL flask by the substantial unfolding of the two innermost pleats while the three outermost pleats are substantially folded and is transformable to accommodate a 250 mL flask by the substantial unfolding of the second and third innermost pleats while the first innermost pleat and the two outermost pleats are substantially folded and is transformable to accommodate a 500 mL flask by the substantial unfolding of the third and fourth innermost pleats while the first and second innermost pleats plus the outermost pleat are substantially folded and is transformable to accommodate a 1000 mL flask by the substantial folding of the innermost two pleats while the outermost three pleats are substantially unfolded.
A device of the many embodiments of the present invention may additionally comprising handle portion. In some embodiments, the device may additionally comprise a rigid or semi-rigid part which may be used as a handle to lift or carry the device.
In other embodiments, the device may additionally comprise a circular band of rigid or semi-rigid material attached to (or near) the device's upper face with the band's diameter parallel with the device's upper face in a manner useful for uniformly folding or unfolding the concentric circular pleats of the device.
In still other embodiments, the device may additionally comprise a partial covering of a second skin or shell, exterior to the first skin or shell, which is substantially thermally-insulating and which is substantially thermally stable at temperatures of 100° C. or greater.
In still further embodiments, the device may additionally comprise a hole, socket, clip or other feature connecting, retaining, or integrating a thermometer, thermocouple or other temperature measuring or heat measuring instrument.
In other embodiments, the device may additionally comprise a flexible polymeric support surface molded to cast the contours of the lowest section of a Thiele tube, or otherwise shaped in a manner so as to be adapted heating and supporting a Thiele tube.
While the specification concludes with claims particularly pointing out and distinctly claiming the present invention, it is believed that the present invention will be better understood from the following description in conjunction with the accompanying Drawing Figures, in which like reference numerals identify like elements, and wherein:
In the following detailed description of the preferred embodiment, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration, and not by way of limitation, a specific preferred embodiment in which the invention may be practiced. It is to be understood that other embodiments may be utilized and that changes may be made without departing from the spirit and scope of the present invention.
The materials of construction of both the skin 5 and the filler substance 6 are chosen from materials which are resistant to substantial degradation when exposed to the range of temperatures the device is expected to experience in normal use; that is, comprising materials which substantially retain their mechanical properties up to temperatures of about 180° C. or greater for practical periods of time. The material of constructions for 5 is chosen from soft, malleable or flexible metals or metal alloys or chosen from high-temperature-resistant organic polymers such as polyimide films. One type of high-temperature-resistant polyimide film is known by the trade name: Kapton (DuPont Chemicals). Most preferentially, the material of construction of 5 is a silicone rubber or a fluorosilicone rubber and, further, 5 preferentially comprises a silicone rubber with superior thermal conductivity, in other words, a material with superior heat conductivity properties. Examples of high-temperature-resistant materials of this type are known in the art as thermal interface silicone rubbers and are materials chosen from various silicone rubber compositions containing substantially-uniform dispersions of filler particles chosen from thermally-conducting metals, minerals, ceramics or other inorganic or organic materials. The chosen thermal interface silicone rubber, preferentially, will have a thermal conductivity greater than 1 W m−1 K−1. In one embodiment the skin/shell, 5, thickness is in the range of about 0.1 mm to 15 mm but preferentially it is about 2 mm in thickness.
The composition of the moldable/malleable/fluid filler material 6 is to be chosen from high-temperature-resistant thermal-transfer fluids, some examples of which are known by the trade names of Paratherm (Paratherm Corp.), Dowtherm (Dow Chemical Corporation), and Therminol (Eastman Chemical Co.). Still other high-temperature-resistant thermal transfer fluids and materials are known to persons skilled in the art. The preferred moldable/malleable filler substance is a silicone oil such as Syltherm XLT HTF, Syltherm 800 Stabilized HTF, Syltherm HF HTF, (all marketed by Dow Chemical Company) or a silicone fluid, silicone grease or silicone paste and, further, 6 is preferentially a silicone oil, a silicone fluid, a silicone grease or a silicone paste containing a substantially-uniform dispersion of substantially thermally-conducting filler particles such as are chosen from particles of various metals, mineral particles, ceramic particles or other inorganic materials. A silicone paste with continuous thermal stability to 200° C. and very high thermal conductivity is marketed under the trade name Omegatherm 201 by OMEGA Engineering, Inc. Heat-Away 6400 is a high-temperature thermally conductive, copper-filled silicone grease marketed by Aremco Product, Inc. and suitable for heat transfer applications from −51° C. to 288° C. Still other suitable high-temperature thermally conductive fluids, pastes or greases are known to persons skilled in the art.
In one embodiment, the device is constructed to form an object or article which is substantially flat on one face (designated as the bottom) and is substantially shaped, on the opposite face, (designated as the top) to form a pocket, socket, cavity or basin such as may conform to the profile of a round-bottomed vessel or to the shape of some other rounded or regularly or irregularly shaped object to be situated or nested in the pocket.
Another embodiment is also shown in
Viewed as a cylinder, changing the device's diameter by compression of (squeezing) the side(s) of the device will cause the incompressible filler fluid to push the top face up and away from the bottom face. In other words, the height of the device will vary inversely with its diameter because the volume of the device will remain essentially constant even as the device is adjusted to accommodate flasks of different capacities.
This embodiment of the present invention further comprises a lifting ring, 3, (
In one embodiment, the lifting ring 3, is encapsulated by a coating, designated as the lifting ring shell, 2, (
In one embodiment, the device or article comprises a partial covering of a second skin or shell, 4, (
Another embodiment of the present invention may comprise a thermocouple integrated with the device or inserted in slots or holes in the device such that the thermocouple probe may be plugged by means of a thermocouple pair of wires into the external temperature control of a hotplate or similar device.
While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims, which themselves constitute part of the disclosure, all such changes and modifications that are within the scope of this invention.
The following references are hereby incorporated herein by reference:
This application is a continuation-in-part of U.S. patent application Ser. No. 15/246,733, filed Aug. 25, 2016, which claims the priority benefit of U.S. Provisional Application Ser. No. 62/210,112, filed Aug. 26, 2015, both of which are hereby incorporated in their entirety herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 62210112 | Aug 2015 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 15246733 | Aug 2016 | US |
| Child | 15628095 | US |
