1. Field of the Invention
This invention relates to carpentry tools. More particularly, the invention relates to a method and apparatus for smoothing unfinished wood or plastic surfaces and edges that are of curved other complex shapes.
2. General Background and State of the Art
Many individuals engage in building products from wood or plastic, either professionally or as a hobby. Enhancement of a person's home or office, for example, is possible by utilizing the tools and techniques known or taught through experience or through researching books or trade journals on the subject.
A wide variety of tools are available to the builder to achieve his or her goals in any building project. Tools vary from the small and simple (pliers, hammers, screwdrivers, to name a few) to the large and complex (lathes, for example). Some tools are powered by hand while others may be powered by electricity. Tools can be used to cut and form simple straight lines or level surfaces. Specialty tools, such as routers, also are available to cut more complex shapes, allowing the individual to form creative and fanciful pieces for purposes of function and/or enhancing the appearance of the finished project.
The process of building a finished product of wood or plastic requires a number of steps. It may be required by the particular project to prepare a piece in some fashion before it is cut. After the piece is cut into its desired configuration, other steps remain, which may include smoothing, polishing, assembling and finishing. Smoothing operations are generally achieved by sanding. Currently, all powered sanding tools are only for flat surfaces. Sanding and polishing of more complex surfaces is achieved through time consuming and painstaking manual sanding and polishing. Some smoothing and polishing of complex surfaces may be attempted by using a router, but there is a risk that the router bit could splinter the piece, therefore ruining the product.
There is no sander currently available that will sand the custom curves and shapes that a router makes on the edges of various projects.
There is no sander currently available that will allow free style sanding with the sanding tubes that are currently widely available.
There is no device currently known that is versatile and will allow the smoothing and polishing of a variety of shapes with easily changeable parts.
Accordingly, it is an object of the invention to provide a multipurpose machine and method that can be used to meet the requirements of virtually any sanding project that involve complex shapes and surfaces.
Another object of the invention is to provide a sanding tool that can be configured into almost any shape to meet the needs of such a project.
A further object of the invention is to allow the easy interchange of parts so that a sanding project can proceed efficiently with little interruption regardless of the variety of complex curves and surfaces encountered.
An additional object of the invention is to enable the use of removable sanding heads that could match the various shapes currently available in standard router heads.
It is yet another object of the present invention to provide a multipurpose machine that could be used in conjunction with standard sanding tubes and paint rollers to allow for freehand sanding and/or polishing over various surfaces and curves.
These and other objectives are achieved by the present invention, which, in a broad aspect, provides a high degree of flexibility and efficiency in allowing the user to sand and polish a wide range of complex surfaces and curves in wood or plastic products.
An apparatus according to one embodiment of the invention utilizes part of an existing rotational variable speed power tool having a driving mandrel extending from the power unit of the tool. The driving head of the mandrel has locking receptacles in the driving head surface that faces away from the power unit. A sanding head having locking flanges at one of its ends is fitted over the mandrel and is fixed to the driving head by inserting the locking flanges of the sanding head into the locking receptacles of the driving head. The sanding head is further secured to the mandrel by means of a threaded fastener that fits into a threaded recess in the end of the mandrel. A shaped abrasive material is adhered to the outside of the sanding head. The abrasive material can be formed into virtually any shape that will conform to the surface or curve that is to be sanded. When it is desired to use the tool to smooth a different shape, the sanding head can be removed and exchanged with another sanding head that is nearly identical in configuration to the first head, except that on the second sanding head the abrasive material is shaped to conform to the next surface that is to be smoothed. It is possible to build a number of interchangeable sanding heads each having an abrasive layer in a unique configuration that will allow for virtually any complex shape or curve to be smoothed by the tool.
Another embodiment of the invention allows the use of a standard sanding tube to be fixed to the driving head of the mandrel by attaching an extension to the threaded recess in the end of the drive shaft of the mandrel so that the combination of mandrel and extension is sized to accommodate the length of a standard sanding tube. The sanding tube can then be fitted over the drive shaft and extension and fixed at the two ends in a manner similar to the way in which the sanding head is fixed to the mandrel. If so desired, a handle may be secured to the end of the extension instead of a threaded fastener. This application allows for free style sanding of the surface that is to be sanded.
The length of the sanding surface can be extended to accommodate more than one sanding tube by the addition of one or more additional extensions, thus extending the sanding surface available to the user. If larger diameter sanding tubes are needed for certain applications, rubber sleeves can be fixed over the drive shaft and the extension(s) prior to fixing the sanding tube(s) to the drive shaft and extension(s).
In another embodiment of the invention, a standard paint roller can be used in much the same way as the sanding tube for free style polishing of surfaces such as surfing boards or skis.
In a further embodiment of the invention, parts of a rotational variable speed tool will be utilized that will enable the use of removable sanding heads that would match the shapes of currently available router heads and also allow the use of standard router bearings.
Further objects and advantages of this invention will become more apparent from the following description of the preferred embodiments, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.
In the following description of the present invention, reference is made to the accompanying drawings, which form a part thereof, and in which are shown, by way of illustration, exemplary embodiments illustrating the principles of the present invention and how it may be practiced. It is to be understood that other embodiments may be utilized to practice the present invention and structural and functional changes may be made thereto without departing from the scope of the present invention.
A method and apparatus for smoothing unfinished surfaces, according to the preferred embodiment of the invention, is embodied in a power tool generally referred to by the reference numeral 10 (
Mandrel 18 is illustrated in greater detail in
To utilize tool 10 in accordance with the present invention, a sanding head 32 is mounted on drive shaft 28 of mandrel 18. Various configurations of sanding head 32 are further illustrated in
Sanding head 32 further includes drive locks 50 mounted on first end 34 (
In practice the assembled tool 10 is used by applying the abrasive material 44 on sanding head 32 to the curve or shape that requires smoothing. Sanding heads having different shapes formed by raised surface 43 and abrasive material 44 can be easily interchanged as needed as the requirements of any sanding projects dictate by removing threaded fastener 48 from threaded recess 46, releasing drive locks 50 from locking receptacles 26, and sliding the sanding head 32 from the tool 10 and replacing it with a similar sanding head having the appropriately-shaped abrasive material 44 on its outer surface 40. While the present invention allows the flexibility of using one tool for smoothing a wide variety of surfaces, an additional advantage of the present invention is that power unit 12 is a variable speed unit, thus allowing very precise control of the smoothing operation.
In addition, the use of vertical depth guide 52 would allow the depth of the sanding head 32 to be controlled in order to further match the curve and depth to match the routed surface. Guide 52 slips over the power unit 12 and set screw 54 adjusts guide 52 to the desired depth. Guide 52 can be positioned so that it almost reaches abrasive material 44. For this embodiment of the invention, I have found that the Multipro, a product made by Dremel of Racine, Wis., provides a suitable base on which to build the finished unit.
Further embodiments of the invention are made possible by extending mandrel 18 to accommodate smoothing fixtures other than sanding heads. In
A third embodiment of the present invention is illustrated in
If a user so desires, hollow handle 72 may be secured to extension 58 by threading handle fastener 76 into threaded receiving port 66. Thrust bearing 74 is embedded in handle 72 to allow the handle to turn freely during operation.
Two sanding tubes 68 may be used in this application by attaching additional extensions as needed to make the overall length of the drive shaft 9 inches. By using two sanding tubes 68 in tandem, the present invention allows sanding over a 9-inch surface or into complex curves of carvings.
If a user desires to use larger size standard sanding tubes (they are available in sizes up to 1½ inches in diameter), a rubber sleeve 70 is placed onto the drive shaft 28/extension 58 combination prior to placing the sanding tube 68 on the apparatus. Rubber sleeves of 4½ inch length are available from the Ridge Tool Company of Elyria, Ohio.
A fourth embodiment of the present invention is illustrated in
An alternative way of mounting paint roller 78 to drive shaft 28 in order to ensure a suitable fit between paint roller 78 and drive shaft 28, is through the use of plastic insert 104, which is fitted onto drive shaft 28 after flanged end cap 80 is secured to drive plate 22 as illustrated in
The foregoing descriptions of exemplary embodiments of the present invention have been presented for purposes of enablement, illustration, and description. They are not intended to be exhaustive of or to limit the present invention to the precise forms discussed. There are, however, other configurations for apparatuses and methods for smoothing unfinished surfaces not specifically described herein, but with which the present invention is applicable. The present invention should therefore not be seen as limited to the particular embodiments described herein, rather, it should be understood that the present invention has wide applicability with respect to sanding and polishing projects. Such other configurations can be achieved by those skilled in the art in view of the descriptions herein. Accordingly, the scope of the invention is defined by the following claims.
This application claims the benefit of U.S. Provisional Patent Application No. 60/381,071 filed May 17, 2002, incorporated herein by reference.
Number | Name | Date | Kind |
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3858368 | Cocherell et al. | Jan 1975 | A |
4897968 | Hutt | Feb 1990 | A |
5439410 | Larsson | Aug 1995 | A |
5681211 | Wiand | Oct 1997 | A |
Number | Date | Country | |
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60381071 | May 2002 | US |