Patent Application
20100111624
1. Field of the Invention
The invention relates to extenders for hole saws or for other cutting tools that are used by plumbers in residential and commercial structures. The extender allows a plumber or other construction worker to provide a passageway through wood or other sawable materials for receiving a pipe. The preferred embodiments comprise an extender that comprises the pipe that the plumber wishes to install in the passageway, and methods that comprise disconnecting the pipe from the saw and power unit and optionally leaving it in place in the passageway for its intended plumbing use.
2. Related Art
Extenders for drilling or sawing at a distance from the user, by means of a hand-held drill power unit, have been developed in the past. For example, the following systems appear in the patent literature: Klein, et al. (U.S. Pat. No. 7,127,972, issued Oct. 31, 2006); DeBlasio (U.S. Pat. No. 6,558,089, issued May 6, 2003); Hanson (U.S. Pat. No. 6,601,478, issued Aug. 5, 2003); Carpinetti (U.S. Pat. No. 5,957,634, issued Sep. 28, 1999); and Carrol (U.S. Pat. No. 5,624,214, issued Apr. 29, 1997); Bowling (U.S. Pat. No. 4,906,146, issued Mar. 6, 1990); Salyers (U.S. Pat. No. 4,474,513, issued Oct. 2, 1984); Emmerich (U.S. Pat. No. 4,206,821, issued Jun. 10, 1980); and Siebrecht (U.S. Pat. No. 4,076,444, issued Feb. 28, 1978).
The invention comprises an extender system for use with a hole saw or other hole-forming tool to allow drilling/sawing of holes to create a passageway through multiple or thick pieces of wood or other materials in a residential or commercial building structure. The passageway receives a fluid flow pipe that connects to fittings for other plumbing in the building structure. The extender system and methods of using the extender system comprise a hollow pipe with only external threads at each end. The preferred methods comprise using the extender system to drill through said multiple or thick wood or other materials, then disengaging the externally-threaded pipe from the any apparatus attached to its ends, and optionally leaving said externally-threaded pipe in place in the passageway that was created with the hole-forming tool, for use in its plumbing capacity. The externally-threaded pipe allows said use of the pipe in its plumbing capacity without the internal threads or other disruptions in the interior surface that typically cause turbulent fluid flow through the pipe and, as a result, the invented system reduces or prevents turbulence-caused pitting, damage, and disintegration of the interior, and, ultimately the entire wall, of the pipe.
Referring to the Figures, there are shown two, but not the only, embodiments, of the invented extender system for drilling/sawing a passageway for a pipe intended for conducting fluids through a building. There is also shown in the Figures, one embodiment of a method for forming a passageway and installing an externally-threaded pipe in said passageway by using an externally-threaded standard fluid plumbing pipe as a portion of the extender system. The preferred forming and installing methods minimize the number of steps and apparatus that must be used to accomplish the plumbing task. While the preferred embodiment is described and drawn as including a hole saw, other cutting or drilling tools may be connected to the distal end of the extender system, for example, any auger-style or self-feeding bits, and/or a spade bit or other drill bit that makes a large hole. Said cutting or drilling tools preferably are selected from those that are capable of making a hole in the range of 1-6 inches. The term “hole-forming tool,” therefore, may be used to include a hole saw, spade bit, and/or other tools that may be installed at the distal end of the extender system for the methods described herein.
The extender system 10 is portrayed in
The preferred embodiments allow the drilling/sawing of the passageway to be done straight and accurately, and the pipe, which is coaxial with the passageway as it is created, remains coaxial with the passageway during use. The pipe 20 is symmetric about its axis, as are, preferably, the bit connector 22 and the saw connector 24, in order to prevent wobbling and/or inaccurate cutting/sawing.
Upon completion of the passageway for plumbing applications, the user and/or assistant(s) may optionally disconnect the pipe 20 of the extender system 10 from the bit connection unit 22 (or “bit connector”), and from the saw connection unit 24 (or “saw connector”), to leave only the pipe 20 remaining in the passageway. The bit connector 22 and the saw connector 24 are removed by unscrewing them from the pipe 20, and no fasteners, screws, set screws, or other fasteners (other than the threads) need be disconnected in order to disconnect the pipe 20 from this adjacent apparatus. No tools are needed to accomplish the disconnection except perhaps for a pipe wrench or other wrench/pliers to grip and turn the bit connector 22/pipe 20 relative to each other, and to grip and turn the saw connector 24/pipe 20 relative to each other. Thus, as best shown in
Details of the preferred embodiment are shown to best advantage in
The bit connector 22 has a bit end 26, with a hexagonal exterior surface, for being received and locked into the power unit 5, and an opposing female end 28 for threadably connecting to the proximal end 21 of the pipe 20. Preferably, no screws, set screws, or other fasteners are used to connect the pipe 20 to the bit connector 22. The female end 28 has internal threads 30 for connecting to the external threads 32 of the proximal end 21 of pipe 20 (see
The saw connector 24 has a proximal female end 38 with internal threads 40 that connect to the external threads 42 of the distal end 23 of the pipe 20 (see
Alternatively, the extender system may have different bit styles, including different bit exterior surface shapes. For example, the bit end 26 of the bit connector 22 may be other polygonal shapes besides hexagonal, may be cylindrical, or may be any shape or style required for adaptation to alternative power units. The bit end 48 of the saw connector 24 also may be other polygonal shapes besides hexagonal, may be cylindrical, or may be any shape or style required for adaptation to alternative power units, and/or any shape or style for adaptation to the female, distal end 44 of the saw connector. For example, bit end 26 may be one shape/style to cooperate with a particular power unit, while the bit end 48 of the hole saw may be another shape/style to cooperate with a particular saw connector 24, and the bit ends 26, 48, therefore, do not necessarily need to be the same shape/style. Good gripping features, such as a polygonal shape are preferred, however, to provide secure and reliable connections during sawing. Note also, that keyed, keyless, or other types of chucks and/or power units may be used.
It may be noted that the simple and durable construction of the preferred extender system 10, and particularly the externally-threaded pipe 20 therein, provides for efficient creation of a passageway for a fluid pipe or for other elements of a building, particularly where at least a portion of the passageway is at a hard-to-reach distance or position relative to the person creating the passageway. In plumbing applications, the preferred extender system 10 allows efficient installation of said pipe in a minimum number of steps, because the pipe element of the extender may be left in place as the pipe for that section of plumbing. In such plumbing applications, a substantial portion of the extender system need not be removed from the holes and spaces through which the drilling/sawing has been done, but instead left there for the ultimate purpose of the project, that is, to have a fluid pipe extend through those holes/spaces for subsequent use when the building is completed/occupied.
The above methods may all be accomplished with a pipe that is optimum for said subsequent use, by virtue of having only external threads (no internal threads), preferably external National Pipe Threads (according to U.S. NPT threaded pipe standards). The external threading provides superior surfaces for fluid flow, by maintaining a non-threaded internal surface inside the pipe that is smooth except for any natural texture or irregularities of the pipe metal, which natural texture or irregularities would be insignificant compared to the roughness created by threads. The externally-threaded pipe interior surface does not cause, or at least does not increase, turbulence in the fluid flow and consequent pitting and damage of the pipe wall, and, hence significantly extends the life of the pipe in its use as a fluid conduit.
The preferred pipe 20 may be any type of metal pipe, typically ½ inch or ¾ inch diameter, with normal iron pipe size (IPS) thread. A ½ inch pipe is expected to be usable with any size drill bit without bending or striping the threads. Most preferably, black iron or galvanized schedule 40 or 80 pipe is used as pipe 20.
In preferred embodiments, therefore, the extender system comprises a bit connector 22 with both a male bit and a female threaded receptacle, and a saw connector 24 with two female ends, one with threads and one with a polygonal or other surface that mates with the hole-forming tool to discourage relative rotation. The saw connector 24 may include set screws to discourage axial movement of the hole-forming tool relative to the saw connector 24. Each of the bit connector 22 and the saw connector 24 will typically be about 3-8 inches long (and more preferably 4-6 inches long). The bit connector 22 and the saw connector 24 may be adapted for use with a keyed chuck on a conventional power unit 5 such as a Jacobs™ power unit that has, for example, a ⅜ or ½ inch chuck. Alternatively, may be adapted for use with a keyless chuck on a conventional power unit such as a Dewalt™ power unit, for example.
The pipe 20 is preferably is a single, continuous piece of pipe having a length in the range of 0.5-21 feet long, depending upon the application and user preference, wherein the bit connector 22 is preferably a single unitary piece with no disconnectable parts, and the saw connector is preferably a single unitary piece with two set screws as its only disconnectable parts. For many applications, a continuous piece of pipe in the range of 3-10 feet long will be effective, but special applications may find a shorter or longer pipe beneficial. All of said pipe, bit connector, and saw connector are preferably all metal.
Although this invention has been described above with reference to particular means, materials and embodiments, it is to be understood that the invention is not limited to these disclosed particulars, but extends instead to all equivalents within the scope of the following claims.
