MXPA97001717A - Comprehensive perforation tool and improved enrosque and met - Google Patents

Abstract

The present invention relates to a method for forming a threaded hole in a workpiece, wherein the orifice has at least two hole portions having different diameters, characterized in that it comprises the steps of: providing a rotating unitary tool, in combination for forming and threading a hole, having an axis with a predetermined axial length, a proximal end and a distal end, the proximal end having a rod, the distal end having an end cutting surface, a bevelling surface adjacent to the cutting surface of end, and a milled thread adjacent and axially behind the beveled surface, provide means for controlling the movement of forming the orifice of the rotary tool in three mutually perpendicular axes, a triordenado system, producing a first portion of the hole having a diameter selectively determined and a first central axis, turning the tool around of its axial length, and helically feeding the beveled surface into the workpiece along the first central axis and moving the end cutting surface along a selectively determined path, having a first selectively adjusted radius, producing a second portion of the hole in the workpiece, the second portion of the hole has a second central axis selectively determined, which is different from the central axis of the first portion of the hole, and a wall, the second portion of the hole is formed by helically feeding the surface cutting edge towards the work piece, and moving the surface on a second selectively determined path, having a second radius selectively adjusted, around the second central axis, and generating threads in at least one of the first and second portions of the orifice with the milling machine of threading, moving the milling machine to thread in a helical path selectively determined, having a third radius selectively adjusted around the first or second central axis respecti

Description

COMPREHENSIVE PERFORATION AND IMPROVED ENRICHMENT TOOL AND METHOD This is a continuation in part of the previous codependent application with serial No. 08 / 301,329, registered on September 6, 1994. TECHNICAL FIELD This invention relates to cutting tools used for drilling and screwed, and more particularly, to an integral tool and a method for using the tool to produce holes having different bevels, counterbores and threaded bores of different shapes, sizes and characteristics as seen and without having to change tools. BACKGROUND Threaded holes and bores are most often produced with multiple tools, typically including a center or point drill to center subsequent tools and create an initial bevel, a hole to create the center hole or bore, a counterbore tool, and a tap to screw the hole. Special drills are known which consolidate the first three tools to produce the bevel, the counter hole and the hole by incorporating multiple diameters into the grinding of the tool. However, the shape of such a tool is complex, and its manufacture and re-milling are generally expensive. Because the diameters of the counterbore and the bevel are ground in the tool, they can not vary in use. Likewise, the length of the hole created in the work piece, as well as the relative lengths of the portions of the bore, is dependent on the length of the corresponding portions of the tool which are predetermined. Other tools are known that have a frosted thread cutter in drill channels in such a way that, after drilling the hole and the bevel, the threads can be milled with the same tool. These tools, however, still can not produce a hole with portions that vary in length, diameter, or distance of the thread from the physical section or sections of the tool from which it was produced. Furthermore, because the bevel portion of the tool is located at the rear of the assembly and requires a full depth bore before the bevel can be formed, the bore is limited to a predetermined depth and the bevel is limited to a predetermined diameter. Moreover, when ductile materials are being drilled, a chip is often formed continuously that is difficult to break. Such long chips can accumulate, become entangled with other chips and / or wrap around the tool, which in turn can create a "bird's nest" from which it is very difficult to get rid of. Accordingly, there is a need for an improved unitary drilling and tapping tool which can make holes of various lengths, characteristics and diameters that are different from the dimensional limitations of the tool, and which reduce the problems of chip removal. SUMMARY OF THE INVENTION An object of the present invention is to obviate the problems and disadvantages described above by creating holes of various lengths, diameters, shapes and kinks. with a unique tool. It is also an object of the present invention to provide a unitary tool that can selectively provide a variety of bores, countershafts and bevels without the need for tool change. Another object of the present invention is to provide a unitary rotating tool and a method that can be created and made screwed into holes having counterbores and bevels over a wide range of diameters, depths and shapes simply by changing the path of the tool. A further object of the present invention is to provide a simplified design for the combination of drilling tools used to produce threaded holes in order that the tools are more easily manufactured and less expensive in their manufacture and re-milling., and that allow the combination of milling operations without repeated tool changes. Another additional objective of the present invention is to obviate the problems of elimination of chips previously known in the industry. Still another objective of the present invention is to provide a unitary tool that allows the selective change of the order and relative size of the characteristics of the bore. A further object of the present invention is to provide a simplified design for the combination of drilling tools used to produce internal or external threads of variable spacing. Yet another object of the present invention is to provide a unitary rotating tool and a method that can be created and made threaded into holes having variable angle beveling. In accordance with one aspect of the present invention, there is provided an improved drilling and tapping tool having an axis of predetermined axial length, distal and proximal ends, where the distal end includes a hole-making element. The hole-making element preferably includes a chamfering surface adjacent to the distal end a counterbore surface axially behind the chamfering surface, and a thread mill located between the counter-bore surface and the proximal end. The bevelling surface is preferably convex in such a way that bevels of various angles can be formed. The preferred thread mill includes one or more rows of teeth that are axially aligned. The counterbore surface will generally have an effective outer diameter that is substantially greater than or equal to the effective external diameter of the thread mill. An alternative embodt may be a counterbore surface that is slightly smaller (e.g., 0.001 inches) than the effective external diameter of the thread mill. The improved drilling and tapping tool can be used to fabricate a coiled or non-cored bore in a workpiece, where there are at least two hole portions having distinctive diameters and depths. For example, the resulting threaded bore may have a bevel and a counterbore of different depths, central axes and diameters, as desired, without the need to change tools. The invention can preferably be implemented in a numerically controlled machine tool with a three axis control. A first bore portion having a selectively determined diameter and a central axis is produced in the workpiece with the drill bit to make holes by axially feeding the drill into the workpiece and moving the milling cutter towards a first selectively determined tool path that has a first radius selected by the machine tool with numerical control. If a non-circular bore is desired, the first path of the tool can be suitably varied to produce such a bore. A second bore portion can be created in the workpiece with a diameter and a central axis that is different from the diameter of the first bore portion. Similarly, the second bore portion is produced with the drill to make holes by axially feeding the drill into the workpiece and moving the drill in a second path of the selectively determined tool having a second radius selectively adjusted with the machine tool numerically controlled. This process can be repeated as many t as desired to produce an almost infinite combination of angles with varying bore profiles, different effective internal diameters, depths and alignments. Similarly, non-circular bores such as lobe counterbores or the like may also be formed, with a suitable modification of the tool path, with or without axial feed of the tool. The thread can be generated within a wall of any portion of the bore with the thread mill by moving the tool in a helically path determined selectively along an appropriate thread radius with the machine tool numerically controlled. Multiple input threads can be generated using a thread mill where every third tooth or plurality of teeth has been removed in such a way that a respective number of input threads will be formed. For example, every third axial thread cutting tooth is removed, a threaded bore having two input threads can be formed. If you eliminate every two teeth, you can form a threaded bore that has three input threads. According to yet another aspect of the pre-invention invention, a drilling and tapping tool is provided where the thread mill has at least one thread cutting tooth. If the thread mill has more than one tooth, all the teeth must be located in the same axial position in the milling cutter in such a way that the variable spacing threads can be formed. This incorporation also has a hole-making element and can include a beveling surface and a counter-drill surface. The counterbore surface preferably will have an effective outer diameter that is substantially less than the effective external diameter of the thread mill. This incorporation is generally used in the same manner as described above except that a bore portion with threads is formed in one operation. For example, a rosin-each portion will generally be formed by axially feeding the thread mill into the workpiece. This operation mills both a bore and a series of rough threads in the bore portion because the effective outer diameter is greater than the effective outer diameter of the bore element, the bevelling surface and the countersunk surface. The threads are then terminated by retracting the tool from the threaded bore along the same path through which it entered. Variable spacing threads can be formed by this tool simply by changing the feed rate of the tool. External threads may also be formed in a workpiece with a tool of the present invention when feeding the tool along a helical rough thread cutting path with a given diameter of the thread about a central axis of the workpiece. job. The threads are optionally terminated by retracting the helical rough thread cutting path in the reverse direction. Similarly, variable dis- tancement threads can be formed by this tool simply by changing the feed rate of the tool. BRIEF DESCRIPTION OF THE DRAWINGS While the specification concludes with clauses that particularly state and distinctly claim the present invention, it is believed that it will be better understood from the following description taken in conjunction with the accompanying drawings in which: Figure I is a cross-sectional elevated side view of a drilling and tapping tool made in accordance with the present invention. FIG. IB illustrates an alternative embodiment of an improved drilling and kinking tool of the present invention and similar to that shown in FIG. A, but showing an element for making concave, modified holes. Figure 1C shows yet another alternative embodiment of the improved drilling and kinking tool of the present invention illustrating an element for making convex holes. Figure ID illustrates yet another alternative embodiment of the improved tool of the present invention, illustrating a combination of a convexly curved bevelling surface and a counterbore surface. Figure 1E discloses yet another alternative embodiment of the improved tool of the present invention illustrating a modified element for making holes. Figure 1F illustrates yet another alternative embodiment of the improved tool of the present invention, wherein the bevel surface is partially curved convexly in its conformation. Figure 1G shows yet another alternative embodiment of the improved tool of the present invention, where the counterbore surface has an effective external diameter that is less than the effective external diameter of. The thread mill and the thread mill have two thread cutting teeth arranged in the same axial location as the screw mill. Figure III illustrates yet another alternative embodiment of the improved tool of the present invention, where every third tooth in the axial rows of teeth of the thread mill has been removed for a multiple entry screw. Figures 2A-E illustrate a series of schematic views illustrating the various process steps of the improved tool of Figure IA forming a threaded bore.

Figure 2F similarly illustrates a schematic view of the internal threads that are being formed using the improved tool of Figure 1F. Figure 2G illustrates a schematic view showing the simultaneous formation of a bevel and a counterbore using the improved tool of Figure 1F. Figures 3A-J show schematic side elevation views of exemplary blind coiled bores that can be produced by the tools and method of the present invention. Figure 4A is a view of the upper plane of a typical tool path created in a x-y plane when the tool is forming a bore having a diameter equal to the diameter of the drill for making holes. Figure 4B is a view of the upper plane of a typical tool path created in a x-y plane when the tool is forming a bore having a diameter greater than the diameter of the drill bit for making holes. Figure 4C is a view of the upper plane showing a typical tool path that is forming threads in a bore, and Figure 4D is a top plane view showing an exemplary non-circular path of the tool that is forming a bore in a customary way DETAILED DESCRIPTION OF THE INVENTION Referring now to the drawings in detail, where similar numbers indicate the same elements in all views, Figures 1A-H show a variety of schematic illustrations of exemplary preferred embodiments of an improved tool. perforation and screw 10 of the present invention. The tool 10 has an axis 15 which is of a predetermined axial length with proximal (e.g. 20) and distal (e.g. 30) ends. The proximal end 20 has a tang 40 for insertion into the chuck jaws or chuck of a drilling apparatus or other machine tool. Adjacent and axially forward of the tang 40 and rearwardly of the distal end 30, there is a thread mill portion 50 which may preferably comprise one or more thread forming teeth 60 aligned in axial rows. As will be seen with respect to the embodiment of Figures 2F and 2G, however, the tool of the present invention can also be provided with a single tooth 60 to allow the formation of variable thread spacing with a single tool. In some tools made in accordance with this invention, a tool 10 can also be formed without thread forming teeth in its thread mill portion 50. However, this is not preferred, as the bores can be formed with or without rosters. - ca regardless of whether the teeth of the drill • are provided in the tool, and for maximum adaptability, one or more teeth are preferred. A hole-making element 70 is preferably placed adjacent to and axially forward of the thread mill 50 at the distal end 30 of the tool 10. The hole-making element 70 has a cutting end surface 80 which is preferably cut-off. central. All cutting surfaces 80 are preferably provided with a suitable chip channel (not shown) to remove chips, especially when milling or drilling small radii bores. The hole-making element 70 also preferably includes a chamfering surface 100 located adjacent to and axially by. behind the cutting surface 80, and a counterbore surface 110 located adjacent to and axially behind the beveling surface 100 to create bevels and counterbores as desired. As will be understood, the substantially flat cutting end surface 80 of the tool of FIG.? A, maximizes the usable thread depth of the hole. The alternative embodiment shown in Figure Ib has a concave cutting end surface 80 to minimize deflection of the tool 10., particularly when milling in a substantially helical tool path having a radius substantially corresponding to the external diameter of the tool. Figures 1C-1F illustrate another alternative embodiment of the tool 10 having a convex cut end surface 80 to provide improved chip control when ductile materials are being cut. As will be understood, the convex surface may comprise curved surfaces (e.g., Figures ID, F and H), distinct angular surfaces (e.g. 1C, E and G) or any variety or combination or surface conformations. Figures 1A-H also show a chamfering surface 100 in the tool 10 preferably located adjacent to and axially rearward of the cutting end surface 80. Figures ID and 1F illustrate incorporation. alternative rations of the tool 10 having a bevelled surface convexly curved 100 to allow interpolation of various angled bevels. Particularly, such a configuration effectively provides a radiated beveling surface that can provide a wide variety of bevel shapes and sizes, limited essentially only by the machine's path control capabilities. However, the radial feed per helical revolution in the embodiment of FIG. ID is limited by the tolerance of the profile of the beveled surface as the generated surface will be to a certain degree festooned. Figure 1E shows an alternative embodiment of the tool 10 having a cutting end surface 80 that effectively incorporates an integral bevelling surface (e.g., 100) to provide the highest possible radial advance rate; however, this end cutting surface 80 may not be suitable due to specifications for maximum hole depth, usable threads, or chip formation problems. Accordingly, the advantage of the tools 10, as shown in Figures ID and 1F, is that the resulting shape of the bevel is not present. For example, single or multiple bevels having a single angle, a multiple angle or a curved angle can be created. Also, the bevel can be formed in different conformations such as substantially circular, oval or trilobal. When the tool 10 will be used only to generate a single bevel angle, then the re-smearing of that particular angle on the surface between beveling grooves 100 allows a maximum axial radial advance per revolution along the path of the tool during the beveling process. Where a tool is contemplated for dedicated use for a particular application, the formation of the drill bit 70 with a predetermined bevelled groove surface angle (e.g., as illustrated in Figures 1A-C, E, and G) may be preferred.

Figures 1A-H show the improved cutting tool 10 of the present invention having generally a counterbore surface 110 located adjacent to and axially behind the bevelling surface 100. As will be appreciated, the axial length (eg l) of the surface Counterbore 110 effectively limits the axial radial advance per helical revolution when a counterbore or hole is produced with the tool. Because increasing the axial length of the counterbore surface 100 would correspondingly increase the maximum effective speed of the radial advancement, the axial length of the skewed cut or relief (eg length u shown in Figure 2E) formed in the bottom of the threaded bore terminated during the threading processes, as will be explained. Preferably, the axial length M (as illustrated in Figures IA and B for example) the thread mill 50 should be equal to or greater than the maximum usable thread depth desired for any particular bore to be formed. The thread mill 50 preferably includes one or more teeth 60 axially aligned in rows. As will be better seen in Figure 1G, an alternative embodiment is contemplated where each third tooth 60 along each axial row is removed in such a way that the multiple entry or starting threads can be formed. Preferably, the diameter D of the spigot 40 (eg as illustrated in Figure 1C) will be equal to or less than the diameter of the thread mill 50 in order to minimize the overall cost of the tool material and to maximize the adaptability of the tool in use. However, in cases where the depth of the counterbore is considerable, and the ratio of the length to the diameter of the tool 10 is undesirable (for purposes of strength and stiffness), the diameter D of the spike 40 can be increased as appropriate. Preferably, the tool 10 has an outer counterbore diameter dx that is substantially greater than or approximately equal to the external diameter of the thread mill d2 as best seen in Figures IA to 1F. Tool 10 as illustrated in Figure 1G, comprises a thread mill 50 and a counter boring surface 100 having an effective external diameter dx that is smaller than the effective external diameter d 2 of the screw mill portion. Preferably, this embodiment also includes at least one thread cutting tooth 60, and is illustrated having two thread forming teeth located in the same axial position in the tool. If the thread mill has more than one tooth, all the teeth must be located in the same axial position in the thread mill so that the variable distance threads can be formed. An alternative embodiment, which will not be illustrated in the drawings, may be a thread mill having at least two thread cutting teeth where one tooth is adjacent to the counterbore surface and the second tooth is axially behind the first tooth . If the profile of the first tooth has a slightly smaller size (eg 0.05 inches) then the distance can be varied by half the amount of the smaller size (eg a size smaller than 0.05 inches would allow a variation of 0.025 in the distance of the thread) . The thread mill is advanced radially and axially in a helical pattern towards the workpiece to form the threads along the desired portion of the wall of the bore. The use of this incorporation for the enrosque of an anima consumes more time; however, the included thread angle (e.g. 60 degrees) remains the same in such a way that a tool can generate different spacings. Consequently, the different distances in the same tool can be formed with this alternative embodiment simply by varying the proportion of axial radial advance. Even though the tool 10 of the present invention can be used to create all types of bores (e.g., through bores, blind holes, etc.), Figures 2A-F illustrate the steps used to create an exemplary blind bore or hole having a bevel, a counter-bore, and threaded bore in a workpiece with a tool 10 as illustrated and described above with respect to Figure IA. Although a person skilled in the field can select a suitable means for controlling the operation of the tool 10, preferably a numerically controlled three-axis machine (not shown) is used. A numerically controlled machine can be pre-programmed to have numerous predetermined toolpaths and manipulation programs can be stored in the controller-, or manual controls can be used to enter the quality control information data before or during the drilling operation . Any suitable control arrangement can be used as determined by an expert in the field, including the operation manual of a manual drilling apparatus.

In addition, the tool 10 can be used with quick-change machine tools selected by those skilled in the art. The use with such quick change machine tools would allow multiple tare drilling operations as part of a larger milling operation. A substantial cost saving would result from the multiple task functions of the tool 10, since fewer tool changes would be required during the operation. As shown in Figure 2A, for example, a first bore or bevel portion 120 is created by beveling the surface between grooves 100 by rotating the tool 10 about its longitudinal axis L and by radially and axially advancing the tool. tool in the work foot-za along a path that has a radius rx, around the center line C of the bevel. The depth and diameter of the bevel 120 can be selectively controlled optimally by control mechanisms. As shown in Figure 2B, a counterbore 130 can be produced by radially and axially advancing the surface between grooves of the counterbore 110 in a path having a radius r2 that is different from the radius rx used to create the bevel 120. The depth of the Counterbore 130 is again determined selectively and preferably controlled by a numerically controlled machine. As those skilled in the art will appreciate, non-circular bores and bevels can also be formed using the tool 10 by moving the tool in a non-circular tool path perpendicular to the tool axis. Non-circular bores of varying depth can be formed by selectively spacing the tool axially on the workpiece. For example, this process could be used to form oblong bores, fulfilled bores, trilobal bores, or serrated bores.

An exemplary non-circular tool path that can be used to create a trilobal bore or counterbore is illustrated in Figure 4D. In addition, at least one non-coaxial bore can be generated by the tool 10 as shown in Figure 3J. As shown in Figure 2C, a bore 140 can also be produced with the same tool 10 by radially and axially advancing the tool 10 to a desired depth in a tool path having a radius r3 that is different from the respective spokes ( eg rx and r2) of the tool paths used to create the bevel 120 and the counterbore 130. Obviously, if the radius r3 were equal to the radius r2, the counterbore. 130 and bore 140 would have the same diameter. As illustrated in Figure 2D, at least one portion of bore 140 can also be screwed (coiled bore 150) with the same tool 10 by retracting tool 10 from bore 140 a distance approximately equal to one and one-half times the thread spacing wanted. The desired helical path and the radius (r4) of the tool path are selected to produce threads (eg longitudinal length, distance, depth, etc.), and the thread mill 50 is advanced radially in the bore 140 in a helical path at least one, and preferably one and a half revolutions of the tool 10 about its axis. Figure 2E shows a completely coiled bore that can be created with the unit tool 10 in the manner described. If more than one starting (or input) thread is desired, the tool 10 can be spaced around the central axis of the bore portion such that the starting threads are equally spaced around the internal diameter of the portion of the bore. soul For example, if starting threads are desired, the tool 10 would be spaced 180 degrees around the central axis of the bore portion and the production step of the helical thread as described above would be repeated once again thus producing two starter threads. Alternatively, the incorporation of the tool 10 illustrated in Figure 1G can be replaced so that at least two starting threads (not shown) can be formed in a single thread milling operation as described herein without having to space the tool 10. for each desired start thread. As will be understood by those involved in the industry, the tool 10 can be used to form multiple entry threads in this manner regardless of whether it has a single thread forming tooth, or a plurality of such teeth. It should also be noted that the exact order of the steps in the process can be altered to some extent. For example, the order to form the bore 140, the counterbore 130 and the bevel 120 can be rearranged as desired. As best illustrated in Figures 2F-G, a preferred embodiment of the tool 10, as illustrated in Figure 1G, can also be used to form roscas within a bore. The bore 140 and the terminated threads 150 are formed by radially and helically advancing the tool 10 to a desired depth in a tool path having a radius r3 that is different from the respective spokes (eg ^ and r2) of the tool paths used to create the bevel 120 and the counterbore 130. Obviously, because the larger effective external diameter (eg dx) of the counterbore surface 110 is smaller than the larger effective external diameter (eg d2) of the reamer thread 50, the depth of the counterbore 130 is limited by the height of the surface of the counterbore 110. The operation of radially advancing and helically the tool 10 of Figure 1G simultaneously drills both the bore and a rough thread of threads finished 150, since the tooth 60 is larger in diameter than the element for making holes 70. By retracting the tool 10 along the same path by the which was advanced will allow the tooth 60 to effectively provide a "finishing step" to produce finished threads 150. A bevel 120 and a counterbore 130 can be formed independently or simultaneously before or after milling the bore 140. Figure 2G illustrates the simultaneous formation of the bevel 120 and the counterbore 130 using a tool 10. The bevel 120 and the counterbore 130 can also be circular or non-circular in shape, limited only by the tool path taken to form these bores. This incorporation of the tool 10 and the combination of thread milling and bore milling method can also be used to externally form threads in a workpiece such as a bolt or spine (not shown in the Figures), by helically moving the tool 10 around the central axis of the workpiece in order to produce a thread with the desired spacing and the main thread diameter. Alternatively, the incorporations of the tool 10, as illustrated in Figures IA to IH, can also be used to form external threads in a workpiece if the helical radial advance rate of the tool 10 is synchronized with the thread spacing of the tool. such that the tool 10 is advanced radially and axially approximately 1.5 times the length of the desired thread spacing. The examples of Figures 3A-3J only serve as examples of the virtually limitless variations of orders and combinations of bore characteristics that may be implemented here. It should also be noted that another key advantage for the present inventive tool resides in its inclusion of a hole making element 70 in front of its thread milling structure 50, and in its location of the beveling surface 100 adjacent to the element. Due to this structure, the tool 10 can be used to make bores of multiple features without changing tools, and bevels of different sizes and shapes can be provided without having to drill to the full depth of the tool to have access to a conventional beveling structure mounted proximally. In a preferred embodiment, the extreme cutting surface 80 of the forwardly located combination 80, the beveling surface 100 and the counterbore surface 100 (e.g. see Figures IA) provides substantially unlinked adaptability and applicability to the tool and method of the present invention. Figures 3A-J show an exemplary variety of blind holes that can be created with a unit tool 10 simply by using the method of this invention. Not every bore has to have all three characteristics, for example, a bevel, a counterbore and a threaded bore, and the order of the location of such features can be varied without requiring changes of tools. In the same way, each characteristic can occur many times in the same anima. Many combinations can therefore be produced depending on the application for which the core is required. As can be appreciated, the biased end of the bore does not appear symmetrical. This is due to the preferred embodiment screwing process where the thread mill is rotated in a helical path for approximately 1.5 revolutions. Figure 3A discloses a threaded bore 140 having a bevel 120a, a counterbore 130, a start bevel 120b and a bore 140 with screwing. This particular combination is substantially as described above with respect to Figures 2A-2E. Figure 3B shows a counterbore 130, followed by a start bevel 120B, and a coiled bore 140. Figure 3C illustrates a coiled bore 140 having a bevel 120a, a counterbore 130, and a start bevel 120b, where the diameter The effective external b of the threaded bore 140 is significantly less than the outer diameter B of the other portions (eg counter bore 130) of the bore. Figure 3D shows a threaded bore of large diameter 140 having a bevel 120a, a counterbore 130, and a start bevel 120b. Figure 3F reveals a threaded bore 140 having a bevel 120a, a counterbore 130, and a start bevel 120b, where the axial length N of the counterbore is relatively longer than those shown in the previous examples.

Figure 3G shows a non-coiled bore 140 having a bevel 120a, a counterbore 130 and a start bevel 120b, where the diameter B of the counterbore is greater than the diameter b of the bore. Note that, because threads are not desired in this bore, there is no biased portion as in the example of Figure 2E described above. Figure 3H shows a coiled bore 140 having a first bevel 120a, a second bevel 120c, a counterbore 130 and a start bevel or third bevel 120b. Figure 3J shows a counterbore 130 having a selectively determined core line or a central axis P of the threaded portion 140 of the bore. This example illustrates another advantage of the unit combination tool 10 subject, where the radial trajectory of the tool for forming the bore portions, especially for the counterbore 130, can be moved to create souls with customary, non-circular shapes, as desired ( for example, oval or trilobal) that may not be coaxial with each other. For example, in some applications, such as aircraft parts, it is critical to provide customary shapes of bores and holes to control tension or alignment of parts. The substantially free form of drive control that can be implemented with the present unit tool 10 allows eccentricities and displacements to be formed in virtually any of the bore characteristics described herein. Figure 3J illustrates such eccentric offset or counterbore 130. It will be understood that the tool paths required to form particular bore characteristics will differ depending on the bore portion that is being created. For example, Figure 4A shows the plane view of a tool path 160 created by the tool 10 when forming a hole having a diameter that is greater than the diameter of the tool 10. Essentially, it is only rotated the tool 10 around its central axis L and radially advancing helically in the workpiece. Figure 4B illustrates the view of the upper plane of the tool conical path 160 created by the tool 10 when it forms a hole having a radius (eg rx) that is greater than the radius of the tool 10. For example, a tool having a curved beveled surface of convex shape that is advanced radially along the tool path illustrated in Figure 4B will create a concave or convex radiated bevel if the ratio of the axial radial advance of the tool 10 is continuously varied during the axial radial advance while maintaining a fixed rate of change for the involute. If the ratio of axial radial advance and the rate of change of the involute are both fixed, a conical surface with a constant bevel angle will be generated. Alternatively, a change in either the axial radial advance rate or the involute rate during axial radial advance will generate a second distinct constant bevel angle adjacent the first bevel angle. Therefore, an almost infinite combination of bevel angles and shapes can be formed adjacent to one or more portions of bore. Figure 4C is also a view of the upper plane of the helical path of the tool 160 of the tool 10 when the tool 10 is forming threads in the hole. Because the tool 10 will rotate about its longitudinal axis L, it will be advanced radially in the workpiece, and will move in a radial direction progressively outwardly to form threads, resulting in the increase of the spiral path of the diameter of the tool. Figure 4D shows a tool path that is not circular, in which there is one or more planes, in such a way as to provide a trilobal bore. Such a tool path can be implemented with or without axial radial advance. The tool 20 can be constructed of many suitable materials depending on the type of application that the tool 10 will carry out. Generally, the most preferred materials include carbide and high speed steel.

Additionally, the performance of a tool made in accordance with this invention can be enhanced with various external coverages such as titanium carbide, titanium nitride, titanium carbonitride, aluminum ti-tanium nitride, diamond, or cubic boron nitride, depending of the application. In addition, overheating of the tool 20 can be obviated by passing coolant through chill openings in the tool (not shown) as is known in the industry. Similarly, the removal of chips can be facilitated by the application of fluid and / or the application of cutting / cooling fluid to the bore during forming operations, as is common in the technology. Having shown and described the preferred embodiments of the present invention, further adaptations of the drilling tool and method that are shown and described herein can be achieved by appropriate modifications of an ordinary technology in the field without departing from the scope of the present invention. Many of these potential modifications have been mentioned, and others will be apparent to those authorized in the field. Accordingly, the horizon of the present invention should be considered in terms of the following clauses and it is understood that it is not limited to the details of structure and operation that are shown and described in the specification and drawings.

Claims (20)

1. NOVELTY OF THE INVENTION Having described the invention, it is considered as a novelty and what is included in the following CLAUSES is claimed: 1. An integral rotary tool for selectively forming and screwing bores, said tool comprising an axis of predetermined axial length having some ends proximal and distal, a pin located adjacent said proximal end, a hole-forming element located adjacent said distal end, a bevelling surface adjacent said hole-forming element, a counter-bore surface located axially behind said beveling surface , and a portion of thread mill disposed between said counterbore surface and said pin.
2. 2. The tool set forth in clause 1, wherein said portion of a thread mill comprises at least one thread cutting tooth.
3. 3. The tool set forth in clause 2, wherein said counterbore surface and said thread mill each have predetermined effective external diameters, said counterbore surface having an effective external diameter that is less than the effective external diameter of said milling cutter. of thread.
4. 4. The tool set forth in clause 3, wherein said thread mill portion comprises a plurality of axially spaced thread cutting teeth.
5. 5. The tool set forth in clause 1, wherein said thread mill portion comprises a countersunk surface and said screw mill has each predetermined effective outer diameter, and said counter drill surface has an effective external diameter that is greater than or approximately equal to said effective external diameter of said thread mill.
6. 6. The tool that is established in the clause 5, wherein said thread mill comprises a plurality of thread cutting teeth spaced axially therebetween to form multiple entry threads.
7. 7. The tool that is set forth in clause 1, wherein said beveling surface further includes a convex surface to selectively form variable angle bevels.
8. 8. The tool that is established in the clause 7, wherein said convex beveled surface comprises a curved surface.
9. 9. A method for forming a threaded bore in a workpiece comprising the steps of: providing a unitary rotating tool of auger and auger formation having an axis with a predetermined axial length, having proximal ends and distal, and a stem said proximal end, said distal end having a hole-forming element, a bevelling surface adjacent said hole-forming element, a counter-bore surface located axially behind said beveling surface, and a portion of a cutter of thread disposed between said counterbore surface and said pin; controlling the movements of the bore formation of said rotation tool in three mutually perpendicular axes of a three-dimensional system; and producing a plurality of bore portions in a workpiece with said tool, where each. of said bore portions has a selectively determined central axis, a selectively determined bore depth and distinctively selected bore radii, and each bore portion is being formed by rotating said tool about its axial length and axially feeding said bore. tool in the workpiece and moving said tool over a drilling tool path selectively determined for said bore depth.
10. 10. The method set forth in clause 9, further comprising the following steps for generating threads in at least one portion of bore with said tool: providing a unitary tool where each of said counterbore surface and said thread cutter have a diameter external cash defaultsaid counterbore surface having an effective outer diameter that is substantially greater than or approximately equal to the effective outer diameter of said thread mill, and said thread mill having a plurality of teeth aligned in axial rows, - retracting said end mill. axially threaded out of said bore portion at a length at least equal to approximately the length of the desired thread spacing; advancing radially and axially said thread mill in a helical tool path having a selectively determined thread radius about said central axis; and moving said tool along said path for at least one revolution along said selectively determined thread radii.
11. The method set forth in clause 9, further comprising the step of producing a second bore portion in said work piece with said tool, wherein said selectively determined central axis of at least two bore portions are not coaxial.
12. 12. The method set forth in clause 9, wherein one of said formed bore portions comprises a bevel adjacent to at least one other bore portion, said bevel being formed by the movement of said bore in an approximate tool bevel path. perpendicular to said axial length of the tool.
13. 13. The method set forth in clause 9, wherein at least one of said bore portions comprises a counterbore formed by said counterbore surface upon moving said tool in a selectively determined counterbore toolpath, perpendicular to said countersunk surface.
14. 14. The method set forth in clause 12, wherein said bevel toolpath is not circular.
15. 15. The method set forth in clause 13, wherein said counter-drill tool path is not circular.
16. 16. The method set forth in clause 10, wherein said step of providing a unitary tool further comprises providing said thread mill with a plurality of thread cutting teeth spaced axially from each other to form at least two inlet threads. .
17. 17. The method set forth in clause 10, wherein said thread generation step further comprises the following steps for forming a multiple start thread in said bore portion: axially retracting said thread mill out of said bore portion to a length at least equal to the length of the desired thread spacing; spacing said tool around the central axis of said bore portion such that said multiple starting threads are approximately equally spaced from each other; radially axially advancing said thread mill in a helical path having a selectively determined thread radius about said axis; moving said tool along said path for at least one revolution along said selectively determined thread radius, and repeating these steps as many times as necessary to create said multiple start threads.
18. 18. The method set forth in clause 9, further comprising the following steps for generating threads in at least one coiled bore portion; providing a unitary tool where each of said counterbore surfaces and said thread mill have a predetermined effective outer diameter, said outer diameter of the counterbore surface being smaller than said effective external diameter of said thread mill, and wherein said mill The thread has at least one thread cutting tooth to form variable distance threads, and generate threads simultaneously with said bore producing step when helically feeding and selectively said tool in said work piece along a thread radius and spacing selectively determined about said central axis.
19. 19. The method set forth in clause 18, further comprising the step of terminating said threads in said bore portion by helically retracting said thread mill from said coiled bore portion.
20. 20. A method for forming external threading on a workpiece having a central axis, said method comprising the following steps: providing a unitary rotating tool of auger and auger formation having an axis with a predetermined axial length, havproximal and distal ends, and a pin said proximal end, said distal end hava hole-formelement, a bevellsurface adjacent said hole-formelement, a counter-bore surface located axially behind said bore. - bevelsurface, and a portion of thread cutter disposed between said countersunk surface and said spike; said counterbore surface and said thread mill each have predetermined effective external diameters, said counterbore surface having an effective external diameter which is less than said effective external diameter of said thread mill, and said thread mill has thus less a thread cutting tooth disposed in the same axial location in said thread mill for cutting variable distance threads, - controlling the movements of the bore formation of said rotation tool in three mutually perpendicular axes of a triordinary system, - producing external rough threads in a work piece spirally feeding said tool in said work piece around said central axis for a selectively determined depth, and finishing said rough threads spirally retracting said thread mill from said thread portion along said axis centrally determined selectively to a proportion i gual to said feeding.