Hole cutter with chip egress aperture
A hole cutter has a substantially cylindrical blade body defining a blade body circumference, a cutting edge formed on one end of the blade body, and an axially-elongated slot formed through the substantially cylindrical blade body. The axially-elongated slot is configured to receive chips flowing from the cutting edge within the interior of the blade body and (i) into the slot, and/or (ii) through the slot, to prevent the collection of such chips within the interior of the blade body and/or at an interface between the blade body and work piece. The axially-elongated slot defines a first end adjacent to the cutting edge, a second end axially spaced further from the cutting edge, and a slot area. The hole cutter further defines a total slot area to blade body circumference ratio within the range of about 0.1 to about 0.3 depending on the size of the hole cutter.
Latest Irwin Industrial Tool Company Patents:
This application is a continuation-in-part of co-pending U.S. patent application Ser. No. 12/687,078 filed Jan. 13, 2010, which is incorporated by reference in its entirety as if fully set forth herein.
FIELD OF THE INVENTIONThe present invention relates to hole cutters, and more particularly, to hole cutters with apertures formed in the side walls thereof.
BACKGROUND INFORMATIONA typical prior art hole cutter includes a cylindrical blade body defining a plurality of saw teeth on the cutting edge of the blade body, and one or more apertures formed through an intermediate portion of the blade body. Typically, smaller diameter hole cutters have fewer apertures formed through the blade bodies, and larger diameter hole cutters have more apertures formed through the blade bodies. The apertures formed through prior art hole cutter blade bodies may define a variety of different configurations to facilitate inserting a tool into the apertures, such as a screw driver, to remove circular work piece slugs from the interiors of the blade bodies.
One of the drawbacks encountered with prior art hole cutters is that chips or dust, particularly when cutting wood, collects within the interiors of the hole cutters between the work piece slugs and the caps on the non-working ends of the hole cutters. The apertures formed in the side walls of the blade bodies are designed to allow the insertion of screw drivers or like tools to remove work piece slugs, but are not configured to allow the chips or dust generated during cutting to flow through the apertures and away from the interiors of the blade bodies. The chips and dust that collect within the interiors of the blade bodies can become compacted and rapidly fill the hole cutters. Chips and dust also collect at the interfaces between the blade bodies and work pieces, such as between the external surfaces of the blade bodies and the work pieces. The chips and dust that collect at the interfaces of the blades bodies and work pieces can become heated due to frictional forces created between the rotating blade bodies, collected chips and dust, and work pieces. The thermal energy created by such frictional forces can be sufficient to cause the paints or coatings on the external surfaces of the blade bodies to become soft or gooey. The collection of chips and dust within the interiors of the blade bodies and/or at the interfaces of the blade bodies and work pieces can significantly reduce the cutting efficiency and overall cutting speed and/or blade life of such hole cutters.
Although many prior art hole cutters include one or more apertures formed through the side walls of the blade bodies, the apertures are not configured to facilitate the flow of chips from the interiors of the blade bodies into and/or through the apertures. In some such hole cutters, the apertures are spaced too far from the cutting edge, such that the chips generated at the cutting edge become packed between the interior of the blade body and the work piece slug prior to reaching the aperture(s). In other such hole cutters, the apertures are too small to allow any material volume of chips to flow into the apertures and/or through the apertures such that the apertures do not materially impact chip egress. In other such hole cutters, the apertures are not configured to cause the chips to flow into or through the apertures and away from the cutting edge and interiors of the blade bodies.
Accordingly, it is an object of the present invention to overcome one or more of the above-described drawbacks and/or disadvantages of the prior art.
SUMMARY OF THE INVENTIONIn accordance with a first aspect, the present invention is directed to a hole cutter or hole saw for cutting a work piece. The hole cutter comprises a substantially cylindrical blade body defining a blade body circumference, a cutting edge formed on one end of the blade body, and an axially-elongated aperture or slot formed through the substantially cylindrical blade body. The axially-elongated slot is configured to receive chips flowing from the cutting edge within the interior of the blade body and (i) into the slot, and/or (ii) through the slot, to prevent the collection of such chips within the interior of the blade body and/or at an interface between the blade body and work piece. The axially-elongated slot defines a first end adjacent to the cutting edge and axially spaced therefrom a first distance within the range of about 15/100 inch to about ⅜ inch, a second end axially spaced from the cutting edge a second distance that is greater than the first distance and is at least about one inch, and a slot area. The hole cutter further defines one of the following: (i) the substantially cylindrical blade body defines a diameter of about 13/16 inch or less, only one of the axially-elongated slots is formed through the blade body, and the slot area to blade body circumference ratio is at least about 0.15; (ii) the substantially cylindrical blade body defines a diameter within the range of about ⅞ inch to about 1 7/16 inches, only two of the axially-elongated slots are formed through the blade body and are angularly spaced relative to each other, and the slot area to blade body circumference ratio is at least about 0.18; (iii) the substantially cylindrical blade body defines a diameter within the range of about 1½ inches to about 3⅜ inches, at least two of the axially-elongated slots are formed through the blade body and are angularly spaced relative to each other, and the slot area to blade body circumference ratio is at least about 0.1; and (iv) the substantially cylindrical blade body defines a diameter of about 3½ inches or greater, more than two of the axially-elongated slots are formed through the blade body and are angularly spaced relative to each other, and the slot area to blade body circumference ratio is at least about 0.1.
In accordance with another aspect, the hole cutter defines one of the following: (i) the substantially cylindrical blade body defines a diameter of about 13/16 inch or less, only one of the axially-elongated slots is formed through the blade body, and the slot area to blade body circumference ratio is at least about 0.13; (ii) the substantially cylindrical blade body defines a diameter within the range of about ⅞ inch to about 1 7/16 inches, only two of the axially-elongated slots are formed through the blade body and are angularly spaced relative to each other, and the slot area to blade body circumference ratio is at least about 0.15; (iii) the substantially cylindrical blade body defines a diameter within the range of about 1½ inches to about 3⅜ inches, at least two of the axially-elongated slots are formed through the blade body and are angularly spaced relative to each other, and the slot area to blade body circumference ratio is at least about 0.1; and (iv) the substantially cylindrical blade body defines a diameter of about 3½ inches or greater, more than two of the axially-elongated slots are formed through the blade body and are angularly spaced relative to each other, and the slot area to blade body circumference ratio is at least about 0.1.
In the currently preferred embodiments of the present invention, the hole cutter defines one of the following: (i) the substantially cylindrical blade body defines a diameter of about 13/16 inch or less, and the axially-elongated slot defines a slot area to blade body circumference ratio within the range of about 0.15 to about 0.25; (ii) the substantially cylindrical blade body defines a diameter within the range of about ⅞ inch to about 1 7/16 inches, and the two axially-elongated slots define a slot area to blade body circumference ratio within the range of about 0.2 to about 0.33; (iii) the substantially cylindrical blade body defines a diameter within the range of about 1½ inches to about 3⅜ inches, and the two or more axially-elongated slots define a slot area to blade body circumference ratio within the range of about 0.1 to about 0.33; and (iv) the substantially cylindrical blade body defines a diameter of about 3½ inches or greater, and the two or more axially-elongated slots define a slot area to blade body circumference ratio within the range of about 0.1 to about 0.25.
In some embodiments of the present invention, the hole cutter defines a direction of rotation that is the cutting direction of the cutting edge, and the first end of the axially-elongated slot defines an edge surface that slopes away from the cutting edge in a direction opposite the cutting direction. Preferably, the first end defines a maximum width of at least about ⅖ inch, the sloped surface is at least about ⅖ inch long, and the sloped surface is at least one of curvilinear and rectilinear. In some such embodiments, the sloped surface is oriented at an acute angle relative to an axis of the blade body within the range of about 35° to about 60°.
In some embodiments of the present invention, the hole cutter defines a direction of rotation that is the cutting direction of the cutting edge, and the second end of the slot is angularly spaced relative to the first end in a direction opposite the cutting direction. The axially-elongated slot is oriented at an acute angle relative to an axis of the blade body. The acute angle is preferably at least about 30°, and more preferably is within the range of about 35° to about 60°.
In the currently preferred embodiments of the present invention, the hole cutter defines one of the following: (i) the diameter of the substantially cylindrical blade body is about 1 7/16 inches or less, and the axially-elongated slot is oriented substantially parallel to an axis of the blade body, and (ii) the diameter of the substantially cylindrical blade body is greater than about 1 7/16 inches, and each axially-elongated slot is oriented at an acute angle relative to an axis of the blade body and slopes away from the cutting edge in a direction opposite a cutting direction.
In accordance with another aspect, the present invention is directed to a hole cutter for cutting a work piece. The hole cutter comprises a substantially cylindrical blade body defining a blade body circumference, a cutting edge formed on one end of the blade body, and means formed through the substantially cylindrical blade body for receiving chips flowing from the cutting edge within the interior of the blade body and (i) into the means, and/or (ii) through the means, for preventing the collection of such chips within the interior of the blade body and/or at an interface between the blade body and work piece. The means defines a first end adjacent to the cutting edge and axially spaced therefrom a first distance within the range of about 15/100 inch to about ⅜ inch, a second end axially spaced from the cutting edge a second distance that is greater than the first distance and is at least about one inch, and an area. The hole cutter defines one of the following: (i) the substantially cylindrical blade body defines a diameter of about 13/16 inch or less, only one of said means is formed through the blade body, and the means area to blade body circumference ratio is at least about 0.15; (ii) the substantially cylindrical blade body defines a diameter within the range of about ⅞ inch to about 1 7/16 inches, only two of said means are formed through the blade body and are angularly spaced relative to each other, and the means area to blade body circumference ratio is at least about 0.18; (iii) the substantially cylindrical blade body defines a diameter within the range of about 1½ inches to about 3⅜ inches, at least two of said means are formed through the blade body and are angularly spaced relative to each other, and the means area to blade body circumference ratio is at least about 0.1; and (iv) the substantially cylindrical blade body defines a diameter of about 3½ inches or greater, more than two of said means are formed through the blade body and are angularly spaced relative to each other, and the means area to blade body circumference ratio is at least about 0.1.
In accordance with yet another aspect, the hole cutter defines one of the following: (i) the substantially cylindrical blade body defines a diameter of about 13/16 inch or less, only one of said means is formed through the blade body, and the means area to blade body circumference ratio is at least about 0.13; (ii) the substantially cylindrical blade body defines a diameter within the range of about ⅞ inch to about 1 7/16 inches, only two of said means are formed through the blade body and are angularly spaced relative to each other, and the means area to blade body circumference ratio is at least about 0.15; (iii) the substantially cylindrical blade body defines a diameter within the range of about 1½ inches to about 3⅜ inches, at least two of said means are formed through the blade body and are angularly spaced relative to each other, and the means area to blade body circumference ratio is at least about 0.1; and (iv) the substantially cylindrical blade body defines a diameter of about 3½ inches or greater, more than two of said means are formed through the blade body and are angularly spaced relative to each other, and the means area to blade body circumference ratio is at least about 0.1.
In the currently preferred embodiments of the present invention, the hole cutter defines one of the following: (i) the substantially cylindrical blade body defines a diameter of about 13/16 inch or less, and the means defines a means area to blade body circumference ratio within the range of about 0.15 to about 0.25; (ii) the substantially cylindrical blade body defines a diameter within the range of about ⅞ inch to about 1 7/16 inches, and the two means define a means area to blade body circumference ratio within the range of about 0.2 to about 0.33; (iii) the substantially cylindrical blade body defines a diameter within the range of about 1½ inches to about 3⅜ inches, and the two or more means define a means area to blade body circumference ratio within the range of about 0.1 to about 0.33; and (iv) the substantially cylindrical blade body defines a diameter of at least about 3½ inches or greater, and the three or more means define a means area to blade body circumference ratio within the range of about 0.1 to about 0.25. In the currently preferred embodiments, each means is an axially-elongated aperture or slot.
One advantage of the hole cutters of the present invention is that the first ends of the axially-elongated slots or like means are axially spaced adjacent to the cutting edge a first distance within the range of about 15/100 inch to about ⅜ inch, and the second ends of the slots or like means are axially spaced from the cutting edge a second distance that is greater than the first distance. The second distance is at least about 1½ inches. As a result, the chips flowing from the cutting edges within the interiors of the blade bodies are allowed to flow into the slots or like means and/or through the slots or like means to, in turn, prevent the collection of such chips within the interiors of the blade bodies and/or at an interface between the blade bodies and work pieces. The relatively close spacing of the first end of each slot or like means to the cutting edge (about 15/100 inch to about ⅜ inch) facilitates the flow of chips into the slot or like means, and the depth of the slot or like means from the cutting edge (at least about 1½ inches) facilitates the flow of chips into and/or through the slot or like means for a wide variety of work piece thicknesses. Yet another advantage of the hole cutters of the present invention is that they define significant slot area to cylindrical blade body circumference ratios of at least about 0.1, and in many sizes of hole cutters, at least about 0.15 or 0.2, which in turn gives rise to substantial slot areas per given blade body diameters. As a result, the relatively large areas of the slots or like means, in combination with the close placement of the first or inlet ends of the slots or like means relative to the cutting edges of the hole cutters, facilitates the flow of chips into and/or through the slots, and in turn prevents the collection of such chips within the interiors of the hole cutters. The relatively large slot areas facilitate in preventing the slots from becoming clogged with chips and/or allow the slots themselves to retain a significant volume of chips, that otherwise would be trapped within the interiors of the blade bodies. Accordingly, the hole cutters of the present invention provide significantly improved chip removal or egress from the interiors of the blade bodies in comparison to prior art hole cutters which, in turn, can lead to significantly improved cutting speeds and/or blade life. Another advantage of some currently preferred embodiments of the present invention is that the slots or like means are oriented at acute angles relative to the axes of the hole cutters to facilitate the flow of chips up and/or through the slots and thus away from the interiors of the blade bodies. Yet another advantage of some currently preferred embodiments of the present invention is that the first or inlet ends of the slots define edge surfaces that slope away from the cutting edge in a direction opposite the cutting direction of the hole cutters to further facilitate the flow of chips up and/or through the slots and thus away from the interiors of the blade bodies.
Other objects and advantages of the hole cutters of the present invention, and/or of the currently preferred embodiments thereof, will become more readily apparent in view of the following detailed description of the currently preferred embodiments and the accompanying drawings.
In
As shown in
As shown in
As shown in
The number of slots 18 formed through the side wall 13 of the hole cutter 10 depends on the size of the hole cutter. As a general rule, the larger the diameter of the hole cutter, the greater is the number of axially-elongated apertures or slots 18 that can be formed through the cylindrical blade body 12. In the currently preferred embodiments of the present invention, relatively small diameter hole cutters (e.g., about 9/16 inch in diameter to about 13/16 inch in diameter) have one slot 18 oriented substantially parallel to the axis X of the hole cutter, larger diameter hole cutters have two slots 18 (e.g., about ⅞ inch in diameter to about 1 7/16 inches in diameter) oriented substantially parallel to the axis X of the hole cutter, still larger diameter hole cutters (e.g., about 1½ inches in diameter to about 3⅜ inches in diameter) have two larger area slots 18 that are oriented at acute angles relative to the axis X of the hole cutter, and still larger diameter hole cutters (e.g., about 3½ inches in diameter to about 6 inches in diameter) have four larger area slots 18 oriented at acute angles relative to the axis X of the hole cutter. In the embodiment of
In the currently preferred embodiments of hole cutters having multiple slots 18, the slots 18 are approximately equally spaced relative to each other about the axis X of the hole cutter, i.e., if there are two slots 18 they are angularly spaced about 180° relative to each other, if there are three slots 18 they are angularly spaced about 120° relative to each other, if there are four slots 18 they are angularly spaced about 90° relative to each other, etc. However, as may be recognized by those of ordinary skill in the pertinent art based on the teachings herein, the slots 18 need not be equally spaced relative to each other, nor do all apertures or slots 18 on the same hole cutter need to define the same aperture or slot configuration or size.
As shown in
The term “chip” is used herein to mean small particles of a work piece formed upon cutting the work piece with the hole cutter, and including without limitation, saw dust, wood dust, wood chips, metal dust, metal chips, dust and/or chips created upon cutting work pieces formed of materials other than wood or metal, and/or including materials or components in addition to wood or metal.
In the illustrated embodiment, the distances D1 and D2 are measured from a plane extending between the tips of unset teeth. However, as may be recognized by those of ordinary skill in the pertinent art based on the teachings herein, these distances, or the distances between other features of the hole cutter 10 and the cutting edge 14, may be measured with respect to any of numerous other reference lines or features that are currently known or used, or that later become known or used, such as from the base of the deepest gullets of the cutting teeth.
As shown in
As described above and shown in
In
Another difference of the blade body 12 in comparison to the blade body 112 described above is in the configuration of the sloped edge surface 128 of the first or inlet end 122 of each slot 118. As can be seen, the first or inlet end 122 of each slot 118 is defined by two curvilinear regions. A first curvilinear region is contiguous to a side edge of the first fulcrum 220A and is defined by one or more relatively small radii R1. A second curvilinear region is contiguous to the first curvilinear region and is defined by one or more larger radii R2. As can be seen, the larger radius R2 imparts a shape to the respective edge of the slot 118 that slopes away from the cutting edge 114 in a direction opposite the cutting direction of the blade 112. In addition, the location and orientation of the first fulcrum 120A, the respective side and the sloped edge surface imparts a relatively wide inlet 122 to the slot 118 to facilitate the flow of chips or dust from the cutting edge 114 into the slot 118. In the illustrated embodiment, the width W2 at the inlet 122 of the slot 118 is within the range of about ⅕ to about ⅗ inch, and in the illustrated embodiment is about ⅖ inch.
As shown in the table of
The terms “nominal shell area” and “nominal circumference” in
As shown in
The currently preferred embodiments of “small” hole cutters defining diameters of about 13/16 inch or less include only one small configuration slot 118 formed through the blade body. These “small” hole cutters define a slot area to blade body circumference ratio that is at least about 0.15, and more preferably is within the range of about 0.15 to about 0.25. The area of each small configuration slot is within the range of about 3/10 inch to about ½ inch, and in the illustrated embodiments, the area of each smaller configuration slot 118 is about ⅖ inch. As described above, the smaller configuration slots 118 are oriented substantially parallel to the axis X of the hole cutter.
As also shown in
As further shown in
As also shown in
In
The primary difference of the blade body 212 in comparison to the blade body 112 described above is that the axially-extending apertures or slots 218 formed in the blade body 112 have two fulcrums 120A, 120C. This results in a smaller slot area than the slot depicted in
Similar to as described above regarding
As also shown in
One advantage of the combination of the location of the inlet or first ends of the slots in relation to the cutting edge (such as the distance between a plane defined by the tips of unset cutting teeth and the inlet edge), the orientation of the slots (such as being angled with respect to a plane defined by the axis of the cutter at an acute angle of at least about 30° and/or including a sloped surface angled away from the cutting direction), and the relatively large slot area to circumference ratios, is that the slots provide for more efficient and effective chip ejection, and therefore, increased cutting efficiency. Another advantage of the hole cutters of the present invention is that the slots can be configured to allow the chips generated during cutting to flow through the slots and away from the interiors of the blade bodies. Yet another advantage of the hole cutters of the present invention is that the slots can prevent the hole cutters from being overcome by the rate at which the chips are generated during cutting and can allow for the proper egress of chips away from the interiors of the hole cutters and/or the interfaces between the blade bodies and work pieces.
The hole cutters of the present invention may include one or more features of the hole cutters disclosed and/or claimed in any of the following patents and patent applications that are assigned to the assignee of the present invention and are hereby expressly incorporated by reference in their entireties as part of the present disclosure: U.S. Pat. No. 8,579,554 issued Nov. 12, 2013 entitled “Hole Cutter with Axially-Elongated Aperture Defining Multiple Fulcrums”; U.S. Pat. No. 8,573,907 issued Nov. 5, 2013 entitled “Hole Cutter With Minimum Tooth Pitch to Blade Body Thickness Ratio”; U.S. patent application Ser. No. 12/687,102 filed on Jan. 13, 2010 entitled “Hole Cutter With Extruded Cap”; U.S. patent application Ser. No. 12/687,052 filed on Jan. 13, 2010 entitled “Coated Hole Cutter”; U.S. Design Pat. D690,334 issued Sep. 24, 2013 entitled “Hole Saw”; and U.S. Design Pat. No. D659,176 issued May 8, 2012 entitled “Hole Saw”.
It may be readily understood by those having skill in the pertinent art from the present disclosure that any of numerous changes and modifications may be made to the above-described and other embodiments of the present invention without departing from the scope of the invention as defined in the appended claims. For example, the hole cutters may be made from any of numerous different materials, in any of numerous shapes, taking any of numerous different dimensions. For example the cutting edge may be made from any of numerous different materials or combinations of materials that are currently known or that later become known. As an example, the cutting edge may be a bi-metal cutting edge, such as bi-metal cutting teeth. As another example, the cutting edge may take any form, pattern, arrangement or configuration that is currently known or that later becomes known, including without limitation tooth patterns that tend to function well in specific applications, hybrid applications or general applications. For example, the cutting teeth may define any of numerous different tooth forms, pitch patterns and/or set patterns. As another example, a single aperture may be provided in the body of the cutter, two or more apertures may be angularly and/or axially aligned with one another, or two or more apertures may be variably spaced angularly and/or axially relative to one another. In addition, the hole cutters may define different numbers of axially-elongated apertures, different aperture configurations, shapes and/or sizes than those disclosed herein. Also, the hole cutters may be used in any of numerous different cutting applications, on any of numerous different work piece materials, such as woods, metals, plastics, composites, resins, stones, fabrics, foams, etc. Further, the blade body may not define any elongated apertures or slots, or the apertures or slots may not be contained within the side walls of the cutters. For example, the apertures may extend to the cutting edge, the top rim of the side wall or cap, or may extend to both the cutting edge and top rim of the side wall or cap to define a channel that extends the entire or substantially entire axial extent of the blade body. For another example, the apertures may include fewer than two fulcrums, or more than three fulcrums. As another example, the sloped surface of the inlet portion of the apertures may be curvilinear, rectilinear and/or a combination of curvilinear and rectilinear edge surface regions. Alternatively, the first or inlet end of the slot need not be sloped. Accordingly, this detailed description of the currently preferred embodiments of the present invention is to be taken in an illustrative, as opposed to a limiting sense.
Claims
1. A hole cutter for cutting a work piece, comprising:
- a substantially cylindrical blade body defining a blade body circumference,
- an annular cutting edge formed on one end of the blade body, and
- an axially-elongated slot formed through the substantially cylindrical blade body and configured to receive chips flowing from the cutting edge within an interior of the blade body and at least one of (i) into the slot, and (ii) through the slot, to prevent the collection of such chips within at least one of the interior of the blade body and an interface between the blade body and the work piece,
- wherein the axially-elongated slot includes at least one fulcrum extending therein,
- wherein the axially-elongated slot defines a first end adjacent to the cutting edge and axially spaced therefrom a first distance selected to be within the range of about 15/100 inch to about ⅜ inch, a second end axially spaced from the cutting edge a second distance that is greater than the first distance and selected to be at least about one inch, and a slot area,
- wherein one of (i) the substantially cylindrical blade body defines a diameter of about 13/16 inch or less, only one of the axially-elongated slots is formed through the blade body, and a slot area to blade body circumference ratio is selected to be at least about 0.13; (ii) the substantially cylindrical blade body defines a diameter within the range of about ⅞ inch to about 1 7/16 inches, only two of the axially-elongated slots are formed through the blade body and angularly spaced relative to each other, and a slot area to blade body circumference ratio is selected to be at least about 0.15; (iii) the substantially cylindrical blade body defines a diameter within the range of about 1½ inches to about 3⅜ inches, at least two of the axially-elongated slots are formed through the blade body and angularly spaced relative to each other, and a slot area to blade body circumference ratio is selected to be at least about 0.1; and (iv) the substantially cylindrical blade body defines a diameter of about 3½ inches or greater, more than two of the axially-elongated slots are formed through the blade body and angularly spaced relative to each other, and a slot area to blade body circumference ratio is selected to be at least about 0.1.
2. A hole cutter as defined in claim 1, wherein one of (i) the substantially cylindrical blade body defines a diameter of about 13/16 inch or less, and the axially-elongated slot defines a slot area to blade body circumference ratio within the range of about 0.13 to about 0.25; (ii) the substantially cylindrical blade body defines a diameter within the range of about ⅞ inch to about 1 7/16 inches, and the two axially-elongated slots define a slot area to blade body circumference ratio within the range of about 0.15 to about 0.33; (iii) the substantially cylindrical blade body defines a diameter within the range of about 1½ inches to about 3⅜ inches, and the at least two axially-elongated slots define a slot area to blade body circumference ratio within the range of about 0.1 to about 0.33; and (iv) the substantially cylindrical blade body defines a diameter of about 3½ inches or greater, and the more than two axially-elongated slots define a slot area to blade body circumference ratio within the range of about 0.1 to about 0.25.
3. A hole cutter as defined in claim 2, wherein the hole cutter defines a direction of rotation that is the cutting direction of the cutting edge, and the first end of the axially-elongated slot defines a sloped edge surface that slopes away from the cutting edge in a direction opposite the cutting direction.
4. A hole cutter as defined in claim 3, wherein the first end of the axially-elongated slot defines a maximum width of at least about ⅖ inch, the sloped edge surface is at least about ⅖ inch long, and the sloped edge surface is at least one of curvilinear and rectilinear.
5. A hole cutter as defined in claim 4, wherein the sloped edge surface is oriented at an acute angle relative to an axis of the blade body within the range of about 35° to about 60°.
6. A hole cutter as defined in claim 2, wherein the hole cutter defines a direction of rotation that is the cutting direction of the cutting edge, and the second end of the axially-elongated slot is angularly spaced relative to the first end of the axially-elongated slot in a direction opposite the cutting direction.
7. A hole cutter as defined in claim 6, wherein the axially-elongated slot is oriented at an acute angle relative to an axis of the blade body.
8. A hole cutter as defined in claim 7, wherein the acute angle is at least about 30°.
9. A hole cutter as defined in claim 8, wherein the acute angle is within the range of about 35° to about 60°.
10. A hole cutter as defined in claim 1, wherein the cutting edge is defined by a plurality of saw teeth including tips and gullets between the tips, and the first distance is measured from either (i) a deepest gullet of the cutting edge, or (ii) a plane extending between tips of unset teeth of the cutting edge.
11. A hole cutter as defined in claim 10, wherein the second distance is at least about 1½ inches.
12. A hole cutter as defined in claim 1, wherein the axially-elongated slot defines a minimum width of about 0.27 inch to allow insertion of a number 2 screwdriver therethrough.
13. A hole cutter as defined in claim 1, wherein the cutting edge is bi-metal.
14. A hole cutter as defined in claim 1, wherein one of (i) the diameter of the substantially cylindrical blade body is about 1 7/16 inches or less, and the axially-elongated slot is oriented substantially parallel to an axis of the blade body, and (ii) the diameter of the substantially cylindrical blade body is greater than about 1 7/16 inches, and each axially-elongated slot is oriented at an acute angle relative to an axis of the blade body and slopes away from the cutting edge in a direction opposite a cutting direction.
15. A hole cutter as defined in claim 1, wherein the blade body defines a wall region extending annularly about the blade body, and extending axially between the cutting edge and the first end of the axially-elongated slot a distance within the range of about 15/100 inch to about ⅜ inch.
16. A hole cutter as defined in claim 1, wherein the axially-elongated slot includes two fulcrums extending therein.
17. A hole cutter for cutting a work piece, comprising:
- a substantially cylindrical blade body defining a blade body circumference,
- an annular cutting edge formed on one end of the blade body, and
- means formed through the substantially cylindrical blade body for receiving chips flowing from the cutting edge within an interior of the blade body and at least one of (i) into the means, and (ii) through the means, for preventing the collection of such chips within at least one of the interior of the blade body and an interface between the blade body and the work piece,
- wherein the means includes at least one fulcrum extending therein,
- wherein the means defines a first end adjacent to the cutting edge and axially spaced therefrom a first distance selected to be within the range of about 15/100 inch to about ⅜ inch, a second end axially spaced from the cutting edge a second distance that is greater than the first distance and selected to be at least about one inch, and a means area,
- wherein one of (i) the substantially cylindrical blade body defines a diameter of about 13/16 inch or less, only one of the means is formed through the blade body, and a means area to blade body circumference ratio is selected to be at least about 0.13; (ii) the substantially cylindrical blade body defines a diameter within the range of about ⅞ inch to about 1 7/16 inches, only two of the means are formed through the blade body and are angularly spaced relative to each other, and a means area to blade body circumference ratio is selected to be at least about 0.15; (iii) the substantially cylindrical blade body defines a diameter within the range of about 1½ inches to about 3⅜ inches, at least two of the means are formed through the blade body and are angularly spaced relative to each other, and a means area to blade body circumference ratio is selected to be at least about 0.1; and (iv) the substantially cylindrical blade body defines a diameter of about 3½ inches or greater, more than two of the means are formed through the blade body and are angularly spaced relative to each other, and a means area to blade body circumference ratio is selected to be at least about 0.1.
18. A hole cutter as defined in claim 17, wherein one of (i) the substantially cylindrical blade body defines a diameter of about 13/16 inch or less, and the means defines a means area to blade body circumference ratio within the range of about 0.13 to about 0.25; (ii) the substantially cylindrical blade body defines a diameter within the range of about ⅞ inch to about 1 7/16 inches, and the two means define a means area to blade body circumference ratio within the range of about 0.15 to about 0.33; (iii) the substantially cylindrical blade body defines a diameter within the range of about 1½ inches to about 3⅜ inches, and the at least two means define a means area to blade body circumference ratio within the range of about 0.1 to about 0.33; and (iv) the substantially cylindrical blade body defines a diameter of about 3½ inches or greater, and the more than two means define a means area to blade body circumference ratio within the range of about 0.1 to about 0.25.
19. A hole cutter as defined in claim 17, wherein the means is an axially-elongated slot.
1150279 | August 1915 | Little |
1234468 | July 1917 | Hamilton |
1494897 | March 1923 | Freye |
2179029 | November 1938 | Barnes |
2312176 | January 1941 | Kotowski |
2319528 | May 1943 | Berbour et al. |
2427085 | September 1947 | Allison |
2473077 | June 1949 | Starbuck, Jr. |
2482439 | September 1949 | Smith |
2633040 | March 1953 | Schlage |
2779361 | January 1957 | McKiff |
2794469 | June 1957 | Shortell |
2852967 | September 1958 | Mueller et al. |
3220449 | November 1965 | Franklin |
3387637 | June 1968 | Ferguson et al. |
3610768 | October 1971 | Cochran |
3810514 | May 1974 | Viscovich |
3880546 | April 1975 | Segal |
3973862 | August 10, 1976 | Segal |
4077737 | March 7, 1978 | Morse |
D282369 | January 28, 1986 | de Villiers |
4652185 | March 24, 1987 | Malrick |
D303118 | August 29, 1989 | Cox |
5007777 | April 16, 1991 | Itokazu |
D317455 | June 11, 1991 | Martin |
5044393 | September 3, 1991 | Jiles |
5049010 | September 17, 1991 | Oakes |
5058620 | October 22, 1991 | Jiles |
5082403 | January 21, 1992 | Sutton et al. |
5171111 | December 15, 1992 | Kishimoto |
5205685 | April 27, 1993 | Herbert |
D342270 | December 14, 1993 | Kwang |
5597274 | January 28, 1997 | Behner |
5651646 | July 29, 1997 | Bamke et al. |
D392297 | March 17, 1998 | Brutscher |
5803677 | September 8, 1998 | Brutscher et al. |
5820315 | October 13, 1998 | Collard |
D408831 | April 27, 1999 | McGregor |
5904454 | May 18, 1999 | Washer |
6152661 | November 28, 2000 | Thrasher |
D438219 | February 27, 2001 | Brutscher |
6341925 | January 29, 2002 | Despres |
6357973 | March 19, 2002 | Chao |
6409436 | June 25, 2002 | Despres |
6588992 | July 8, 2003 | Rudolph |
6599063 | July 29, 2003 | Casstran |
D478339 | August 12, 2003 | Morton et al. |
D478919 | August 26, 2003 | Morton et al. |
6623220 | September 23, 2003 | Nuss et al. |
6641338 | November 4, 2003 | Despres |
6676343 | January 13, 2004 | Burk |
6746187 | June 8, 2004 | Alm |
6786684 | September 7, 2004 | Ecker |
6893194 | May 17, 2005 | Jones et al. |
6948574 | September 27, 2005 | Cramer et al. |
D516594 | March 7, 2006 | Morton |
7097397 | August 29, 2006 | Keightley |
7101124 | September 5, 2006 | Keightley |
7160064 | January 9, 2007 | Jasso |
7163362 | January 16, 2007 | Keightly |
7189036 | March 13, 2007 | Watson |
7237291 | July 3, 2007 | Redford |
D551269 | September 18, 2007 | Burke, III |
D588175 | March 10, 2009 | Morton |
7556459 | July 7, 2009 | Rompel et al. |
7611312 | November 3, 2009 | Miyanaga |
7637703 | December 29, 2009 | Khangar et al. |
8579554 | November 12, 2013 | Novak et al. |
8579555 | November 12, 2013 | Novak et al. |
20040042861 | March 4, 2004 | Capstran |
20050214086 | September 29, 2005 | Nicholas |
20050244238 | November 3, 2005 | Burk |
20060130629 | June 22, 2006 | Rompel et al. |
20060285934 | December 21, 2006 | Keightley |
20070003386 | January 4, 2007 | Keightley |
20070036620 | February 15, 2007 | Keightley |
20070110527 | May 17, 2007 | Jasso |
20070166116 | July 19, 2007 | Olson et al. |
20070212179 | September 13, 2007 | Khangar et al. |
20070269280 | November 22, 2007 | Vasudeva et al. |
20080019785 | January 24, 2008 | Keightley |
20080050189 | February 28, 2008 | Keightley |
20080181738 | July 31, 2008 | Capriotti et al. |
20080187405 | August 7, 2008 | Nordlin |
20080260480 | October 23, 2008 | Keightley |
20090035082 | February 5, 2009 | Singh |
20090044674 | February 19, 2009 | Neitzell |
20090169317 | July 2, 2009 | Rae |
201 01 718 | May 2001 | DE |
2006-321024 | November 2006 | JP |
- International Search Report and Written Opinion of the International Searching Authority for International Application No. PCT/US2011/021219, mailed Apr. 26, 2011.
- Petition for Inter Partes Review of U.S. Pat. No. 8,579,554, Jun. 22, 2015. 55 pages.
- Office Action mailed Mar. 5, 2013 for U.S. Appl. No. 12/687,065, 26 pages.
- “fulcrum.” Webster's Dictionary. Merriam-Webster, 2009. p. 139.
- Declaration of James Pangerc from Petition for Inter Partes Review of U.S. Pat. No. 8,579,554. Signed and dated Jun. 22, 2015. 11 pages.
Type: Grant
Filed: Jan 13, 2011
Date of Patent: Jun 7, 2016
Patent Publication Number: 20110170967
Assignee: Irwin Industrial Tool Company (Huntersville, NC)
Inventors: Joseph Thomas Novak (Longmeadow, MA), Matthew Christopher Green (Amherst, MA)
Primary Examiner: Eric A Gates
Assistant Examiner: Paul M Janeski
Application Number: 13/006,117
International Classification: B23B 51/04 (20060101);