ROUTER BIT
20170203465 ยท 2017-07-20
Inventors
Cpc classification
B27G13/002
PERFORMING OPERATIONS; TRANSPORTING
B23C2210/54
PERFORMING OPERATIONS; TRANSPORTING
International classification
B23C5/10
PERFORMING OPERATIONS; TRANSPORTING
Abstract
A router bit for use with a turning implement comprising a router bit body having a shank body adjacent a cutting body for forming a key hole in a work piece. The shank body has an outer surface configured to be received by the turning implement. The cutting body has a body portion that spans between a tapered head portion and a tapered end portion, the tapered end portion attached to the shank body. The tapered head portion has a plunge cutting surface that forms a first acute angle with the longitudinal axis. The shank body has a diameter that is smaller than the diameter of the tapered head portion. The tapered end portion has a diameter that varies along its length from the shank body to the tapered head portion to reduce breakage of the router bit body during use. A wing may be attached to the cutting body.
Claims
1. A router bit for use with a turning implement, comprising: a router bit body having a shank body adjacent a cutting body; the shank body having a longitudinal axis, the shank body having an outer surface configured to be received by the turning implement; and the cutting body attached to the shank body along the longitudinal axis, the cutting body having a tapered head portion opposite a tapered end portion and a body portion that spans between the tapered head portion and the tapered end portion, the tapered end portion attached to the shank body, wherein the tapered head portion has a substantially flat end surface opposite a rim and a plunge cutting surface that spans between the substantially flat end surface and the rim.
2. The router bit of claim 1, wherein the plunge cutting surface forms an acute angle with the substantially flat end surface.
3. The router bit of claim 2, wherein the acute angle is between about 3 degrees and 15 degrees.
4. The router bit of claim 1, wherein the substantially flat end surface has a first diameter, the rim has a second diameter, wherein the first diameter is larger than the second diameter.
5. The router bit of claim 4, wherein the body portion has a circular cross-sectional shape with a third diameter that is smaller than the second diameter of the rim.
6. The router bit of claim 1, wherein the body portion has a length that spans along the longitudinal axis of between about 0.10 inches to about 0.25 inches.
7. The router bit of claim 1, wherein the tapered end portion has a substantially circular cross-sectional shape with a diameter that increases along a length of the tapered end portion that extends from the body portion to the shank body.
8. The router bit of claim 1, further comprising: a wing attached to the cutting body, wherein the wing has a primary cutting edge that extends a distance away from the plunge cutting surface and a secondary cutting edge that extends a distance away from the body portion.
9. The router bit of claim 1, further comprising: a flute that extends from the tapered head portion to at least the tapered end portion.
10. A router bit for use with a turning implement, comprising: a router bit body having a shank body adjacent a cutting body; the shank body having a longitudinal axis, the shank body having an outer surface configured to be received by the turning implement; and the cutting body attached to the shank body along the longitudinal axis, the cutting body having a tapered head portion opposite a tapered end portion and a body portion that spans between the tapered head portion and the tapered end portion, the tapered end portion attached to the shank body, wherein the tapered head portion has a plunge cutting surface that forms a first acute angle with the longitudinal axis.
11. The router bit of claim 10, wherein the first acute angle is between about 3 degrees and 15 degrees.
12. The router bit of claim 10, wherein the tapered head portion has a length of about 0.125 inches as measured along the longitudinal axis.
13. The router bit of claim 10, further comprising: a wing attached to the cutting body, wherein the wing has a primary cutting edge adjacent a secondary cutting edge, the primary cutting edge extends a distance away from the plunge cutting surface, and the secondary cutting edge extends a distance away from the body portion.
14. The router bit of claim 13, wherein the primary cutting edge forms a second acute angle with the longitudinal axis.
15. The router bit of claim 14, wherein the first acute angle is substantially the same as the second acute angle.
16. The router bit of claim 13, wherein the wing includes an end surface that extends at an acute angle relative to the longitudinal axis.
17. The router bit of claim 13, wherein the secondary cutting edge extends substantially parallel to the longitudinal axis.
18. The router bit of claim 10, further comprising: the shank body having a distal end opposite a proximal end wherein the proximal end is attached to the tapered head portion; and a flute that extends from the tapered head portion to at least the proximal end of the shank body.
19. The router bit of claim 10, wherein the tapered head portion has a substantially flat end surface opposite a rim and the plunge cutting surface spans between the substantially flat end surface and the rim.
20. The router bit of claim 19, wherein the substantially flat end surface has a first diameter and the rim has a second diameter, wherein the first diameter is larger than the second diameter.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0025]
[0026]
[0027]
[0028]
[0029]
[0030]
[0031]
[0032]
[0033]
[0034]
DESCRIPTION OF THE SELECTED EMBODIMENTS
[0035] For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended. Any alterations and further modifications in the described embodiments, and any further applications of the principles of the invention as described herein are contemplated as would normally occur to one skilled in the art to which the invention relates. One embodiment of the invention is shown in great detail, although it will be apparent to those skilled in the relevant art that some features that are not relevant to the present invention may not be shown for the sake of clarity.
[0036] Referring to
[0037] The shank body 24 has a cylindrical shape with an outer surface 26 and a length L1 that together span from a proximal end 28 to a distal end 30. The outer surface 26 is configured to be received by the turning implement and in the illustrated embodiment the outer surface 26 is smooth. The outer surface 26 may vary in other embodiments such as including grooves, indentations, or other mechanisms for engagement with the turning implement. The shank body 24 has a diameter that may be between about 0.25 inches to about 1.5 inches and in one form is about 0.5 inches and a length L1 that may be between about 0.5 inches to about 4 inches and in one form is 2.0 inches.
[0038] The cutting body 22 is monolithic with the shank body 24 but may be attached to the shank body 24 in another form. The cutting body 22 has a length L2 that spans between a proximal end 32 opposite a distal end 34 wherein the proximal end 32 is adjacent to and attached to the distal end 30 of the shank body 24. The cutting body 22 has a tapered head portion 36 opposite a tapered end portion 38 and a body portion 40 that spans between the tapered head portion 36 and the tapered end portion 38.
[0039] The tapered head portion 36 has a substantially flat end surface 41 opposite a rim 42 and a plunge cutting surface 44 that spans between the substantially flat end surface 41 and the rim 42. The substantially flat end surface 41 is substantially circular in shape and has a first diameter D1. When the router bit 20 is used with a turning implement, the circular shape of the end surface 41 forms a circular opening or entry hole in the pocket such as a tab opening in the key hole as described in U.S. Publication No. 2015/0147113 A1. As the router bit 20 travels from the opening that is formed in the work piece along a length of the work piece in a horizontal direction relative to the work piece, the end surface 41 being substantially flat forms a flat bottom surface of the pocket or key hole. The flat bottom surface of the pocket or key hole in the work piece is perpendicular relative to an end surface of a dowel or key such that the end surface of the dowel or key rides along the flat bottom surface of the work piece when the key is assembled with the key hole or pocket. The end surface 41 is substantially flat to plunge into the work piece, and beneficially the end surface 41 does not wear down as compared to a pointed tip on a drill bit that would wear down much faster. The rim 42 is substantially circular in shape and has a second diameter D2. The tapered head portion 36 has a length L3 that spans between the flat end surface 41 and the rim 42 such that the rim 42 is offset a distance from the flat end surface 41 that corresponds to the length L3. The first diameter D1 of the flat end surface 41 is larger than the second diameter D2 of the rim 42 to create a larger entry hole or tab opening in a work piece for inserting a fastener or key into the pocket. The first diameter D1 may vary from 0.2 inches to about 1.0 inch and in one form is about 0.35 inches. The offset between the first diameter D1 of the end surface 41 and the second diameter D2 of the rim 42 and the length L3 of the tapered head portion 36 form a first acute angle . The plunge cutting surface 44 is oriented as determined by the first acute angle . The first acute angle may be between about 3 degrees and 15 degrees and in one form is 9 degrees. The length L3 of the tapered head portion 36 may be about 0.125 inches as measured along the longitudinal axis L and may be between 0.010 inches to about 0.50 inches.
[0040] The body portion 40 has a circular cross-sectional shape with a third diameter D3 that is smaller than the second diameter D2 of the rim 42. The second diameter D2 may be about 0.255 inches and may range from about 0.125 inches to about 0.75 inches. The body portion 40 has a substantially smooth outer surface. The body portion 40 has a length L4 that spans along the longitudinal axis L between the tapered head portion 36 and the tapered end portion 38. The length L4 of the body portion 40 may be between about 0.10 inches to about 0.25 inches and in one form is 0.188 inches. Since the third diameter D3 is the smallest diameter of the cutting body 22, it is also vulnerable to more wear and breakage when the router bit 20 is used with a turning implement as compared to either the tapered head portion 36 or the tapered end portion 38. The length L4 of the body portion 40 is minimized to reduce breakage of the router bit 20 during use thereof and is critical in the life and the strength of the router bit 20. Because the body portion 40 has the smallest diameter as compared to the diameters of the tapered head portion 36 and the tapered end portion 38, it is important to keep length L4 as short as possible to avoid breakage of the router bit 20. If the length L4 is too long or the diameter D3 is too small, the body portion 40 will be too brittle and will break while attempting to create the pocket or the groove slot portion of the keyhole.
[0041] The tapered end portion 38 is attached to the distal end 30 of the shank body 24 and spans between the body portion 40 and the shank body 24. The tapered end portion 38 has a substantially circular cross-sectional shape with a diameter D4 that increases along a length L5 of the tapered end portion 38 as measured from the body portion 40 to the shank body 24. The tapered end portion 38 has a proximal region 46 that has the same diameter as the third diameter D3 of the body portion 40. The tapered end portion 38 has a distal region 48 that has the same diameter as the distal end 30 of the shank body 24. The distal region 48 is a substantially wider diameter than the proximal region 46 of the body portion 40.
[0042] The router bit body 21 has a recess or flute 56 that extends from the distal end 34 of the cutting body 22 to the distal end 30 of the shank body 24. Flute 56 is an arc shaped recess that extends from an outer surface 26 of the cutting body 22 towards the longitudinal axis L. In another form, the flute 56 may not extend fully to the longitudinal axis L from the outer surface of the cutting body 22. Flute 56 is configured for removing chips or curls from a work piece and/or allowing lubricants or coolants to reach the distal end 34 of the cutting body 22. Flute 56 supplants about or 25% of the cross-sectional area of the cutting body 22 and extends the full length of the cutting body 22 which includes lengths L3, L4, and L5 of the tapered head portion 36, the body portion 40, and the tapered end portion 38, respectively. Flute 56 also supplants about or 25% of the cross-sectional area of the distal end 30 of the shank body 24. In the illustrated embodiment, flute 56 extends a portion P1 of the length L1 of the shank body 24. Flute 56 may supplant more or less of the cross-sectional area of the distal end 30 of the shank body 24 and extend more or less than portion P1 of the length L1 of the shank body 24. Alternatively, flute 56 may not extend into the shank body 24 thereby eliminating portion P1 such that flute 56 stops at the tapered end portion 38.
[0043] The router bit body 21 has a wing 60 attached to the cutting body 22 along the flute 56. The wing 60 has a primary cutting portion 62 adjacent a secondary cutting portion 64. The wing 60 has a thickness T that is constant along a length L6 of the wing 60. The primary cutting portion 62 has a length L7 and a length L8 that span between an end surface 68 and a first lip 70. As such, the end surface 68 forms an angle relative to the end surface 41 as measured between length L7 and length L8. The angle can range from about 1 degree to about 30 degrees but can be larger or smaller in other embodiments. The length L7 and the length L8 of the primary cutting portion 62 are larger than the length L3 of the tapered head portion 36. The lengths L7 and L8 of the primary cutting portion 62 extend beyond the end surface 41 along the longitudinal axis L such that the primary cutting portion 62 will engage and contact a work piece before length L3 of the tapered head portion 36 would contact the work piece when the router bit 20 is positioned perpendicular to the work piece. The engagement of the lengths L7 and L8 of the primary cutting portion 62 enable the primary cutting portion 62 to cut into a work piece when the router bit 20 initially plunges into the work piece. Specifically, when the router bit 20 rotates and plunges into a work piece to create an opening, the longer lengths L7 and L8 of the primary cutting portion 62 initially cut into the work piece If the lengths L7 and L8 of the primary cutting portion 62 end at the tapered head portion 36 such that the end surface 41 and the end surface 68 are planar and flat relative to each other, then the primary cutting portion 62 would not cut or plunge easily and cleanly into the work piece. If the lengths L7 and L8 of the primary cutting portion 62 and length L3 of the tapered head portion 36 ended in the same plane, then the tapered head portion 36 and the wing 60 would be flush against the work piece. The lengths L7 and L8 of the primary cutting portion 62 are longer than the length L3 of the tapered head portion 36 to further enable the primary cutting portion 62 to cut into the work piece as the router bit 20 moves across the work piece. The primary cutting portion 62 has a primary cutting edge 66 that spans between the end surface 68 and the first lip 70 wherein the primary cutting edge 66 is positioned a distance away from or offset from the plunge cutting surface 44 as illustrated in
[0044] The secondary cutting portion 64 has a secondary cutting edge 74 that spans between the first lip 70 and a second lip 72 and a length L9 that spans between the first lip 70 and the second lip 72. The length L9 of the secondary cutting edge 74 ends at the intersection of the body portion 40 and the tapered end portion 38. The secondary cutting edge 74 is positioned a distance away from or offset from the body portion 40. The secondary cutting edge 74 extends substantially parallel to the longitudinal axis L. Alternatively, the secondary cutting edge 74 may extend at an angle relative to the longitudinal axis L. The secondary cutting portion 64 has a second lip 72 that extends substantially perpendicular from the longitudinal axis L to the secondary cutting edge 74. The first lip 70 has a longer length than the second lip 72.
[0045]
[0046] A material to be drilled may also be provided 108. The material may be a composite or may be any material through which a hole may be desirably drilled, such as wood, metal, masonry, etc.
[0047] The drilling machine and router bit 20 may be used 110 to drill or cut a keyhole or pocket in the provided material. This may include using a vacuum to hold the material against a spoil board or otherwise fixing the material in a vise or jig in order to prevent the material from moving while drilling or cutting. In the case of an NC machine, this may include programming the NC machine to drill or cut in desired locations. In the case of a hand drill motor, the user may hold the material in place by hand.
[0048] The drilling machine and router bit 20, in particular, the tapered head portion 36 and the wing 60 may be used to form the tab opening, the bottom surface of the key hole, and the end portion of the key hole as described in U.S. Publication No. 2015/0147113 A1. In particular, the first lip 70 and the primary cutting edge 66 of the primary cutting portion 62 create the ramp and the dowel seat of the key hole as described in U.S. Publication No. 2015/0147113 A1. The body portion 40 creates the groove slot portion of the key hole as described in U.S. Publication No. 2015/0147113 A1.
[0049] The methods disclosed herein comprise one or more steps or actions for achieving the described method. The method steps and/or actions may be interchanged with one another without departing from the scope of the present invention. In other words, unless a specific order of steps or actions is required for proper operation of the embodiment, the order and/or use of specific steps and/or actions may be modified without departing from the scope of the present invention.
[0050] While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes, equivalents, and modifications that come within the spirit of the inventions defined by following claims are desired to be protected. All publications, patents, and patent applications cited in this specification are herein incorporated by reference as if each individual publication, patent, or patent application were specifically and individually indicated to be incorporated by reference and set forth in its entirety herein.