CUTTING TOOL FOR CHAMFERING A WORKPIECE

Abstract

A cutting tool (10) adapted to rotate relative to a workpiece and to chamfer the workpiece, comprising: a body (20) having a connecting end (21) at a first end for engaging a drive tool (90) and a cutting end (22) at a second end, and having a space (23) for receiving the workpiece, at least one projecting part having an edge defining at least one cutting edge (24) for cutting the workpiece and at least one recess (26) for receiving pieces that are to be cut off or removed from the workpiece.have been chamfered, to leave the body (20), wherein the cutting end (22) has an annular inner periphery and an annular outer periphery, the inner periphery bounding the space (23) and defining at least one projecting part and at least one recess (26), the at least one projection projecting radially from the inner periphery in a direction away from the outer periphery, and the at least one recess (26) extending radially from the inner periphery in a direction towards the outer periphery and through the outer periphery; . wherein the space (23) has an upper end and a lower end and tapers outwardly from the upper end to the lower end and has an annular opening at the lower end; wherein the at least one cutting edge (24) has a first end adjacent to the upper end of the space (23) and a second end adjacent to the lower end of the space (23) and extends obliquely from the first end to the second end; wherein the body (20) is rotatable about a first axis (C), the first axis (C) extending longitudinally between the first and second ends of the body (20); and wherein the at least one cutting edge (24) extends obliquely on a second axis (L), wherein the second axis is at an angle (θ) with respect to the first axis (C) and where the angle (θ) is in a range between 30 degrees and 68 degrees.

Description

BACKGROUND OF THE INVENTIONThe present invention relates to a cutting tool, and more particularly to a cutting tool adapted to rotate with respect to a workpiece and to bevel the workpiece.Generally, it is easy to engage a screw with a nut, but it becomes difficult if the screw is rusted or covered with dirt or damaged. Therefore, a screw press die which can provide threads is generally used to chamfer damaged threads or to remove dirt from the screw. However, when such a screw press die is used, it is necessary to be careful to avoid cutting threads that do not suffer from the stated problems. Therefore, it is inconvenient to use a screw press die to bevel the damaged threads or to remove dirt from the screw.DE 11 2014 002 284 T5 describes a deburring tool having a hollow upper region with an inner cone surface and an outer surface. The outer surface of the deburring tool is preferably conical. A plurality of grooves are formed in the upper portion and extend between the inner surface and the outer surface. Each of the grooves has a cutting edge formed on the inner cone surface.EP 2 769 798 A1 describes a milling cutter comprising a main body having a surface having a cup-shaped concavity for receiving an end of an electrode; two slits opening radially into the concavity to receive cutting blades of complementary shape, the edge of which extends away from a wall of the concavity; and a focusing unit for grinding a side of the electrode.US 3 242 526 A describes a device for shaping the shaft ends of candles to fit easily into the sockets of candle holders and posts of various types. More particularly, the invention relates to an apparatus for easily forming a tapered configuration at the shaft ends of candles.US 3 365 773 A describes a deburring tool formed with either a conical inner surface or a conical outer surface, comprising a cutting blade detachably mounted in the surface and at least two bearing strips in the bearing surface for engagement with the end of a pipe whose burr is to be removed by the cutting blade.The present invention therefore seeks to avoid or at least alleviate the problems encountered in the prior art.SUMMARY OF THE INVENTIONThe invention is defined by the features of the independent claim.According to the present invention, a cutting tool comprises a body having a connecting end at a first end for engaging a driving tool and a cutting end at a second end having a space for accommodating the workpiece, at least one protruding part having an edge defining at least one cutting edge for cutting the workpiece, and at least one slot (recess for short) for allowing chips chamfered from the workpiece to leave the body. The cutting end has an annular inner periphery and an annular outer periphery. The inner periphery defines the space and defines at least one protruding part and at least one recess. The space has an upper end and a lower end and tapers outwardly from the upper end to the lower end and has an annular opening at the lower end. The at least one protrusion protrudes radially from the inner periphery in a direction away from the outer periphery. The at least one recess extends radially from the inner periphery in a direction toward the outer periphery and through the outer periphery. The at least one cutting edge has a first end adjacent to the upper end of the space and a second end adjacent to the lower end of the space and extends obliquely from the first end to the second end. The body is rotatable about a first axis, and the first axis extends longitudinally between the first and second ends of the body.It is therefore an object of the present invention to provide a cutting tool adapted to chamfer a workpiece.It is another object of the present invention that the cutting tool is adapted to bevel a threaded fastener.It is yet another object of the present invention that the cutting tool does not unduly cut off the threaded fastener nor that it eliminates a number of threaded portions.It is yet another object of the present invention that the cutting tool easily and quickly disengages the chamfered pieces from the threaded fastener.It is yet another object of the present invention that the cutting tool avoids the difficulty of alignment as set forth.Brief Description of the DrawingsFIG. 1 is a perspective view of a cutting tool according to the present invention. FIG. 2 is a plan view of the cutting tool according to the invention. FIG. 3 is a cross-sectional view of the cutting tool of the present invention. FIG. 4 is a cross-sectional view of the cutting tool of the present invention taken along line 4- 4 of FIG. 3. FIG. 5 illustrates the cutting tool of the present invention being operated to bevel a workpiece.DETAILED DESCRIPTION OF THE INVENTIONFigures 1 through 5 show a cutting tool 10 according to the present invention. The cutting tool 10 is adapted to rotate with respect to a workpiece and bevel the workpiece.The cutting tool 10 includes a body 20 having a connecting end 21 at a first end for engaging a driving tool 90, and a cutting end 22 at a second end and having a space 23 for receiving a workpiece, at least one protruding part having an edge defining at least one cutting edge 24 for cutting the workpiece, and at least one recess 26 for allowing pieces or chips chamfered from the workpiece to leave the body 20. The body 20 is an integral structure.The cutting end 22 has an annular inner periphery and an annular outer periphery. The inner periphery defines the space 23 and defines at least one protruding part and at least one recess 26. The space 23 has an upper end and a lower end and tapers outwardly from the upper end to the lower end. The space 23 has a first diameter at the upper end and a second diameter at the lower end. The second diameter is larger than the first diameter. The space 23 has an annular opening at the lower end. The workpiece to be chamfered by the cutting tool 10 can be inserted into the space 23 through the opening of the space 23. The at least one protrusion protrudes radially from the inner periphery in a direction away from the outer periphery. The at least one cutting edge 24 has a first end adjacent to the upper end of the space 23 and a second end adjacent to the lower end of the space 23 and extends obliquely from the first end to the second end. The at least one recess 26 extends radially from the inner periphery in a direction toward the outer periphery and through the outer periphery. The at least one recess 26 has a first end adjacent to the upper end of the space 23 and a second end adjacent to the lower end of the space 23 and extends obliquely from the first end to the second end and along the at least one cutting edge 24. The inner periphery of the cutting end 22 defines two peripheral regions. The at least one protruding part has a first side extending between the edge and a first one of the two peripheral regions and a second side extending between the edge and a second one of the two peripheral regions. The first and second peripheral portions are recessed and each defines a recess 25. The at least one protruding part has the first side with a first inclination and the second side with a second inclination. The second slope is greater than the first slope. The at least one recess 26 extends between the second peripheral region and the edge and the at least one protruding part.In the embodiment, a number of the plurality of cutting edges 24 and a number of the plurality of recesses 26 are the same. In the embodiment, the plurality of cutting edges 24 are circumferentially separated from each other, and the plurality of recesses 26 are circumferentially separated from each other.The body 20 is rotatable about a first axis C, and the first axis C extends longitudinally between the first and second ends of the body 20.In a plane P that is perpendicular to the first axis C and extends across the inner periphery of the cutting end 22, the at least one cutting edge 24 defines a point and that is at a first radial distance from the first axis C. Further, in the plane P, other radial distances between points defined by the inner periphery of the cutting end 22 and the first axis C are larger than the first radial distance.In order to prevent the cutting tool 10 from unduly cutting the threaded fastener and eliminating the number of threaded portions, the one cutting edge 24 obliquely extends on a second axis L which is at an angle θ with respect to the first axis C, and the angle θ is in a range between 30 degrees and 68 degrees.FIG. 5 shows that the cutting tool 10 is provided with a threaded fastener 91 (e.g., screw). The space 23 in the cutting end 22 receives one end of the threaded fastener 91. The cutting tool 10 is rotated. The at least one cutting edge 24 almost engages the threaded fastener 91. The chamfered pieces experience a centrifugal force in the space 23 and leave the body 20 through the at least one recess 26 The cutting tool can be driven by a drive tool 90. Preferably, the drive tool 90 is an electric tool.In view of the foregoing, the cutting tool 10 is adapted to bevel the threaded fastener 91 without unduly eliminating a number of threaded portions. The recesses 26 allow the cutting tool to easily and quickly release the chamfered pieces.

Claims

A cutting tool (10) adapted to rotate with respect to a workpiece and bevel the workpiece, comprising: a body (20) having a connecting end (21) at a first end for engaging a driving tool (90), and a cutting end (22) at a second end, and having a space (23) for receiving the workpiece, at least one protruding part having an edge defining at least one cutting edge (24) for cutting the workpiece, and at least one recess (26) for allowing pieces chamfered from the workpiece to leave the body (20), the cutting end (22) having an annular inner periphery and an annular outer periphery, the inner periphery defining the space (23) and defining at least one protruding part and at least one recess (26), wherein the at least one protrusion protrudes radially from the inner periphery in a direction away from the outer periphery, and wherein the at least one recess (26) extends radially from the inner periphery in a direction toward the outer periphery and through the outer periphery; wherein the space (23) has an upper end and a lower end and tapers outwardly from the upper end to the lower end and has an annular opening at the lower end; wherein the at least one cutting edge (24) has a first end adjacent to the upper end of the space (23) and a second end adjacent to the lower end of the space (23) and extends obliquely from the first end to the second end; wherein the body (20) is rotatable about a first axis (C) and the first axis (C) extends longitudinally between the first and second ends of the body (20); and wherein the at least one cutting edge (24) extends obliquely on a second axis (L), wherein the second axis is at an angle (θ) with respect to the first axis (C), and wherein the angle (θ) is in a range between 30 degrees and 68 degrees.The cutting tool (10) of claim 1, wherein the at least one cutting edge (24) defines a point in a plane (P) that is perpendicular to the first axis (C) and extends across the inner periphery of the cutting edge (24), and that is at a first radial distance from the first axis (C), and wherein in the plane (P), other radial distances between the points defined by the inner periphery of the cutting edge (22) and the first axis (C) are greater than the first radial distance.The cutting tool (10) according to any one of the preceding claims, wherein the at least one recess (26) has a first end adjacent to the upper end of the space (23) and a second end adjacent to the lower end of the space (23) and extends from the first end to the second end obliquely and along the at least one cutting edge (24).The cutting tool (10) according to any one of the preceding claims, wherein the inner periphery of the cutting edge (22) defines two peripheral regions, wherein the at least one protruding part has a first side extending between the edge and a first one of the two peripheral regions and a second side extending between the edge and a second one of the peripheral regions, wherein the first and second peripheral regions are recessed and each defines a recess (25), and wherein each of the first and second peripheral regions extends radially in the direction toward the outer periphery (22) of the cutting edge (22).The cutting tool (10) according to any one of the preceding claims, wherein the at least one protruding part has the first side with a first inclination and the second side with a second inclination, and wherein the second inclination is greater than the first inclination.The cutting tool (1β) according to any one of the preceding claims, wherein the at least one recess (26) is positioned adjacent to the at least one cutting edge (24).The cutting tool (10) according to any one of the preceding claims, wherein the at least one recess (26) extends between the second peripheral region and the edge of the at least one protruding part.The cutting tool according to any one of the preceding claims, wherein the cutting end (22) comprises a plurality of cutting edges (24) and a plurality of recesses (26), and wherein the number of the plurality of cutting edges (24) and the number of the plurality of recesses (26) are the same.The cutting tool (10) of any preceding claim, wherein the plurality of cutting edges are circumferentially separated from each other and wherein the plurality of recesses (26) are circumferentially separated from each other.

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