Plastic and nonmetallic article shaping or treating: processes – Direct application of electrical or wave energy to work
Reexamination Certificate
1999-03-24
2001-09-18
Barrera, Ramon M. (Department: 2832)
Plastic and nonmetallic article shaping or treating: processes
Direct application of electrical or wave energy to work
C264S427000
Reexamination Certificate
active
06290894
ABSTRACT:
FIELD OF THE INVENTION
This invention relates to a ferrofluid assembly and, more specifically, to an apparatus for producing novel magnetic sculptures for amusement and educational purposes.
BACKGROUND OF THE INVENTION
Magnetic materials have been used for amusement and educational purposes. For example, containers with magnetic materials have been used before to provide interesting designs based on the magnetic properties of the fluid. Magnetic gels have been designed that respond to a magnet, allowing a gel mass to be attracted and moved by a magnet “wand” for purposes of a demonstration. Two patents cover these different types of uses. The first patent is U.S. Pat. No. 3,648,269 entitled “Magnetic Fluid Display Device,” incorporated herein by reference for all purposes. The second is U.S. Pat. No. 5,810,640 entitled “Magnetic Gel Toy and Method For Making.”
U.S. Pat. No. 3,648,269 discloses a display device that includes an opaque magnetic ferrofluid and a transparent fluid immiscible with the ferrofluid within a sealed display housing. The display housing can be a cylindrical container or a flat, rectangular, “sandwich” type construction that is transparent for viewing. Different types of ferrofluids are disclosed and include water-based ferrofluids, hydrocarbons, fluorocarbons, and the like.
Unfortunately, the different types of ferrofluid materials disclosed in U.S. Pat. No. 3,648,269 suffer from several problems. One such problem is that the ferrofluid wets the surface of the display housing such that spots and smears form on the inside of the housing surface. The spotting mars the view of the display and eventually reduces the amount of free ferrofluid which forms the display. An additional problem is that the ferrofluid may degenerate over time such that its responsiveness to magnetic fields degrades compared to the initial state of relatively fresh ferrofluid. The combination of these two problems severely reduces the shelf-life of the display.
U.S. Pat. No. 5,810,640 discloses magnetic gel materials that are used as toys, play things, and novelties. Magnetic materials are mixed with a play gel that has a soft, thixotropic property to produce a magnetic gel. Using this gel, various types of play applications are possible. These play applications include resilient plastic covered forms, template action figure body forms, flowers, and volcanoes with various shaped openings. A magnetic tool or “wand” is utilized to attract the magnetic gel in a desired direction.
The magnetic gel disclosed in U.S. Pat. No. 5,810,640, suffers some of the same problems above, as well as other problems now presented. For example, by the very nature of the disclosed gel, the magnetic gel is much more viscous than the ferrofluid used in previous applications stated above. As such, the magnetic gel is slow to respond to a magnetic force and is too thick to allow a definition of a magnetic field to be imposed on it. Furthermore, since the gel is exposed to air, it can dry out over time and become hardened to the point of not responding to a magnetic field as intended.
Accordingly, what is needed is a new type of magnetic apparatus which allows free form sculptures or artistic patterns to be generated by magnetic fields. This magnetic apparatus uses a ferrofluid to form the sculpture. The ferrofluid should have a low enough viscosity that it is quickly shaped along the lines of magnetic force applied to it, it does not agglomerate when placed in a container over long periods of time, and it has great longevity and stability over prior systems.
SUMMARY OF THE INVENTION
In accordance with one embodiment, magnetic sculptures are formed by placing a ferrofluid in a shaped magnetic field. In response to the field, the ferrofluid forms fanciful sculptures and art forms as determined by the magnetic field lines. The magnetic field lines are evident by the formation of distinct spikes in the ferrofluid.
In one embodiment, a low viscosity ferrofluid is used in a sealed housing to prevent the ferrofluid from evaporating. The housing is filled with a nonmagnetic liquid that is immiscible with the ferrofluid and contains a ferrofluid globule. In order to prevent the ferrofluid from wetting the inside surface of the housing and degrading the apparatus, the housing is comprised of a boro-silicate glass and the ferrofluid comprises a fluorocarbon carrier liquid. Magnetic sculptures can be formed by applying an external magnetic field of sufficient strength to the apparatus so as to create the magnetic field lines of desired shape within the apparatus. The ferrofluid has a low viscosity, low surface tension and high enough magnetization that allows it to define sharp spikes pointing along the field line path of a magnetic field and, accordingly, the field lines are evident by the formation of a pattern of distinct spikes in the globule which together form a fanciful art form. The shape and size of the sculpture can be varied by changing the shape and strength of the applied magnetic field.
In another embodiment, the aforementioned apparatus may contain a small permanent magnetic located within the ferrofluid globule which magnet can move within the housing for generating an internal magnetic field. The ferrofluid globule encases the permanent magnet. The permanent magnet can interact with an externally applied magnetic field to form different sculptured forms depending on the orientation of the internal magnet with the external field.
In still another alternative embodiment, magnetic sculptures are formed in the open air by using an apparatus which comprises an object for receiving a ferrofluid and a mechanism which generates a magnetic field to shape the ferrofluid. The mechanism may include a magnet which generates a shaped field, a shaped magnet or a shaped magnetically permeable pole piece and a magnet. The ferrofluid is a hydrocarbon- based ferrofluid or another ferrofluid type such as ester, glycol, fluorocarbon, silicone or silahydrocarbon of sufficient magnetization, low viscosity, low surface tension and low volatility so that the ferrofluid forms intricate designs based on the magnetic field used to shape the ferrofluid and the sculpture is stable.
In yet a further embodiment, ferrofluid can be mixed with a solid material that has a low melting point, such as a wax. When the material incorporating the ferrofluid is melted, magnetic sculptures can be formed with the liquid melt using one of the techniques used in the aforementioned embodiments. With the magnetic field present, the material is allowed to solidify, making the magnetic sculpture permanent. The magnet can then be removed.
REFERENCES:
patent: 4025448 (1977-05-01), Sudol
patent: 5916641 (1999-06-01), McArdle et al.
Lennon John
Raj Kuldip
Barrera Ramon M.
Ferrofluidics Corporation
Kudirka & Jobse LLP
LandOfFree
Ferrofluid sculpting apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Ferrofluid sculpting apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ferrofluid sculpting apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2526992