Cutlery – Cutting tools – Saw
Reexamination Certificate
2002-03-07
2003-05-27
Shoap, Allan N. (Department: 3724)
Cutlery
Cutting tools
Saw
C030S390000, C030S391000
Reexamination Certificate
active
06568088
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to the field of portable power cutting tools. More particularly, the present invention relates to the field of attachment plates for assisting the movement of portable power circular saws.
2. Description of the Prior Art
Portable power circular saws are widely used. Most conventional circular saws come with a flat plate attached to the bottom of the circular saw. When the circular saw is in use to cut a workpiece, the bottom plate of the circular saw comes in contact with the workpiece and slides on the workpiece as the circular saw is moving forward along the cutting direction. However, this often requires extra effort from the user of the circular saw to overcome the friction between the bottom pate of the circular saw and the workpiece.
It is highly desirable to provide a wheel attachment apparatus that attaches roller wheels to the bottom plate of a circular saw that reduce the friction between the bottom plate and the workpiece being cut. It is also desirable to provide a wheel attachment apparatus that can be an after-market item for quick and easy installation on existing circular saws to provide a set of wheels attached to the bottom plate of a circular saw to reduce the friction between the bottom plate and the workpiece.
BRIEF SUMMARY OF THE INVENTION
The present invention is a novel and unique wheel attachment apparatus for a portable power cutting tool.
It is an object of the present invention to provide a wheel attachment apparatus that is attached to the bottom plate of a circular saw for reducing the friction between the bottom plate and the workpiece being cut.
It is also object of the present invention to provide a wheel attachment apparatus that attaches wheels to the bottom plate of a circular saw, where the wheels are positioned and aligned such that they will always ride on the remaining portion of the workpiece being cut, so that the circular saw is continuously supported throughout the cutting process even when the cut-off portion of the workpiece being cut becomes lose and separated from the remaining portion of the workpiece being cut.
It is another object of the present invention to provide a wheel attachment apparatus that is an after-market item for quick and easy installation on existing circular saws to provide a set of wheels attached to the bottom plate of a circular saw to reduce the friction between the bottom plate and the workpiece being cut.
It is a further object of the present invention to provide a wheel attachment apparatus that is an original equipment manufacture (OEM) item that comes with new circular saws which provides a set of wheels attached to the bottom plate of a circular saw for reducing the friction between the bottom plate and the workpiece being cut.
Described briefly in general terms, the wheel attachment apparatus of the present invention is designed for a portable power cutting tool having a cutting blade driven by a power unit for cutting a workpiece into a cut-off portion and a remaining portion. The power cutting tool has a bottom plate which is to be placed above the working piece to support the cutting tool during a cutting process. The wheel attachment apparatus include two wheel mounting pieces for supporting a set of roller wheels. The wheel mounting pieces are attached to the bottom plate and each has a mounting portion and two outward extending arms. A respective one of the wheels is pivotally mounted to each outward extending arm.
When the cutting tool is used to cut the workpiece, the set of wheels is brought into contact with the workpiece and elevates the bottom plate so that there is no contact between the bottom plate and the workpiece and instead the wheels are rolling on the workpiece to reduce any friction between the bottom plate and the workpiece and ease the movement of the power tool during the cutting process.
In addition, the wheels are positioned and aligned in a way such that they are all on the same side of the cutting blade as the power unit so that they are always rolling on the remaining portion of the workpiece to ensure that the power tool is always firmly supported by the remaining portion of the workpiece throughout the cutting process, even when the cut-off portion of the workpiece becomes lose and separated from the remaining portion of the workpiece.
The present invention has many advantages. It provides a set of wheels attached to the bottom plate of a circular saw to reduce the friction between the bottom plate and the workpiece being cut. It can be an OEM item where the wheels are pre-installed on the bottom plate of new circular saws, or an after-market item where the wheels can be installed on the bottom plate of existing circular saws. An important novel feature and advantage of the present invention wheel attachment apparatus is the positioning and alignment of the wheels which ensure that the wheels will always ride on the remaining portion of the workpiece being cut. As a result, even when the cut-off portion of the workpiece being cut becomes lose and separated from the remaining portion of the workpiece being cut, the circular saw is continuously supported by the remaining portion of the workpiece being cut throughout the cutting process.
REFERENCES:
patent: 1428506 (1922-09-01), Krebs
patent: 1563844 (1925-12-01), Gerlach
patent: 2673725 (1954-03-01), Coates
patent: 2736311 (1956-02-01), Coates
patent: 4456303 (1984-06-01), Due
patent: 4891858 (1990-01-01), Wachter
patent: 4921308 (1990-05-01), Yelton et al.
patent: 4938201 (1990-07-01), Chiuminatta et al.
patent: 5305729 (1994-04-01), Chiuminatta et al.
patent: 5381780 (1995-01-01), Yelton et al.
patent: 5540210 (1996-07-01), Jones
patent: 5669371 (1997-09-01), Rupprecht et al.
patent: 5785293 (1998-07-01), Ford et al.
patent: 5826893 (1998-10-01), Snoeyenbos
patent: 6019433 (2000-02-01), Allen
patent: 6079931 (2000-06-01), English et al.
patent: 6109625 (2000-08-01), Hewitt
patent: 6112736 (2000-09-01), Bearden
patent: 6179542 (2001-01-01), Haven
patent: 6345829 (2002-02-01), Mueller
patent: 6349712 (2002-02-01), Halstead
patent: 6478666 (2002-11-01), Berger et al.
Chen Tony D.
Prone Jason
Rozsa Thomas I.
Shoap Allan N.
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