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SYSTEM DB? (ACC? JNAME DESCRIPTION OF THE INVENTION The present invention relates generally to a novel drive system that provides increased resistance to torsional stresses imposed on the driving system of a bolt with head. It contemplates a novel drive system which is provided by increased resistance to resist the torsional cut between a drive head and a bolt body by providing a novel transitional portion between the drive head and the body. The former head has been formed with drive heads at one drive end thereof For example, using the TORX® drive head, the male portion of the drive head is formed at a free end of the pin. TORX® drive has been previously formed, in a necessary way, with a diameter that is men or to the diameter of the threaded root formed in the body of the bolt in order to avoid the formation of a thread in the projections of the TORX® drive head. The TORX® drive head can cut the bolt as a result of the torsional stresses imposed on the drive head which is greater than the strength of the material between the head of the
"," Drive and bolt body. The present invention provides a novel drive structure that improves the above structure to provide additional resistance to the torsional cut of the drive head of the bolt body by providing a trailing portion between the drive head and the bolt body. Other features and advantages of the present invention will become apparent upon reading the attached specification together with a study of the drawings. A general object of the present invention is to provide a novel drive system that provides increased resistance to torsional stresses imposed on the drive system of a head bolt. It is an object of the present invention to provide a novel drive system that provides increased resistance to the torsional cut of resistance between a drive head and a bolt body by the provision and a novel transitional portion between the drive head of the body. Another object of the present invention is to provide a drive system that when coupled into a socket, the effective cross-sectional area of the network and the last torsional resistance increases? • - * 8? '
by changing the location of potential fracture to the transitional portion. A further object of the present invention provides a drive system that when coupled with a plug provides greater coupling between the plug and the fastener on which it is provided in the prior art structures. In summary, and in accordance with the foregoing, the present invention describes a drive system that includes a body, such as a threaded belay body or a drive tool body, a tapered transitional portion at one end of the body, and a drive head at the end of the transitional portion, such that the transitional portion is between the drive head and the body. The transitional portion has a structure therein such as a plurality of alternating curved projections and folds, for coupling with a corresponding plug. A portion of the folds and a portion of the protrusions • are screwed into the transitional portion. The drive head also has a structure thereon for coupling with the plug, such as a plurality of alternating curved projections and folds. The folds in the transitional portion align axially with the folds in the drive head in the projections in the transitional portion are aligned axially with the projections. in:!% •. a8dlohamiento head,:? 7 * BRIEF DESCRIPTION OF THE DRAWINGS The organization and form of the "structure and operation of the invention, together with other objects and advantages thereof, can be better understood by reference to the following description, taken together with the accompanying drawings. , where similar reference numbers identify <; similar elements in which: FIGURE 1 is an exploded perspective view 10 of a driving end of an insurer and a driving tool, the driving tool is shown partially in cross section, wherein the insurer incorporates the characteristics of a first embodiment of the invention; FIGURE 2 is a view in lateral elevation of an insurer of FIGURE 1;
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embodiment of the invention; FIGURE 6 is a side elevational view Fl securing of FIGURE 5; FIGURE 7 is a cross-sectional view of the driving end of the fastener of FIGURE 5; FIGURE 8 is a front plan view of the insurer of FIGURE 5; and FIGURE 9 is a perspective view of an insurer and which incorporates the features of a third embodiment of the invention. Although the invention may be susceptible to the embodiment in different forms, it is shown in the drawings, and specific embodiments will be described in detail with the understanding that the present disclosure should be considered an exemplification of the principles of the invention, and it is not intended to limit the invention in what is illustrated and described herein. The present invention provides a novel drive system 20. The drive system 20 is provided as a head bolt and is described with respect to the sample in the drawings as an insurer 22. It should be noted, however, that the invention should be used in any torque transmission or torsion coupling application, wherein a drive unit is expanded to transmit the torque to a drive unit A is shown in FIGS. 1-4. A second embodiment of the drive system 20 is shown in FIGS. 5-8. In each of these embodiments, the drive system 20 provides increased resistance to resist torsional cutting between a drive head 24 and an elongate body 26 by providing a novel transitional portion 28 between the drive head 24 and the body 26 A third embodiment of the drive system 20 is illustrated in FIGURE 9. In this third embodiment, only the drive head is removed. The arrangement of the fastener 22 and the drive tool 30 shown in the drawings illustrates a particular application of the invention wherein the fastener 22 is provided with the drive head 24 and the transitional portion 28 having an external configuration formed in accordance with the principles of the present invention, although the complementary drive tool 30 is provided with a plug 32 having a complementary internal configuration that receives the external configuration provided in the belay 22. Those skilled in the art will readily realize that the situation it can be reversed so that the drive tool 30 can be used in the external configuration
according to the present invention although the insurer 22 may include the plug > 32 that has the complementary internal configuration. The elongate body 26 has a thread 34 formed therein and defining a central line or central axis of the adjuster 22. The transitional portion 28 is provided at the end of the body 26. The drive head 24 is unthreaded and is provided at the free end of the transitional portion 28. The transitional portion 28 has a first and second opposite end, with the second end connected to the end of the body 26. The transitional portion 28 tapers from its first end to its second end and has a first series of sections 38 and a second series of sections 40 that alternate around the circumference thereof. That is, by driving the track around the circumference of the transitional portion 28, a section 38 is found, then section 40 is found, then section 38 is found, then section 50 is found, and so on around the circumference of the transitional portion 28. The first series of sections 38 in the second series of sections 40 extend in the axial direction along the length of the transitional portion 28. Each section 38, as shown in the drawings, takes the shape of a fold 38 formed from a curved surface that is
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it directs radially inward towards the center line 3ß of the fastener 22. Each section 40, as shown in the drawings, takes the form of a projection 40 formed from a curved surface which is directed radially outward from the centerline 36 of the fastener 22 As such, the folds 38 depress toward the center line 36 of the fastener 22 relative to the projections 40. The adjacent curved surfaces forming the respective folds 38 and projections 40 emerge generally, tangentially and smoothly from each other. The configuration of the alternating folds 38 and projections 40 define the external configuration of the transitional portion 28. The folds 38 and projections 40 are equally spaced around the circumference of the transitional portion 28 and in the illustrated embodiment, six folds 36 are provided at the first series and six projections 40 are provided in the second series. Attention is directed to the first modality of the transitional portion 28 shown in FIGURES 1-4. The folds 38 and the projections 40 are tapered from the first end to the second end of the transitional portion 28 at the same angle relative to the centerline 36 of the fastener 22, see FIGURE 3. A portion of each fold 38 near the second end of the fold. the transitional portion 28 is threaded with at least one thread 42. A portion of each projection proximal to the
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second end of the working portion 28 is threaded with at least one thread 42. The threads 42 in the folds 38 and in the projections 40 run in alignment with each other and with the threads 34 formed in the body 26 according to the threads 34, 42 are formed in the body 26 and in the projections 40 of the transitional portion 28 in a conventional thread roll forming operation as described herein. Only the portions of the folds 38 and the projections 40 having the same diameter as the root thread 34 is screwed into the body 26. The tension is directed to the second embodiment of the transitional portion 28 shown in FIGS. 5-8. The pleats 38 taper from the first end towards the second end of the transitional portion 28 at an angle relative to the center line 3-6 of the fastener 22 that is greater than the angle at which the projections 40 are tapered from the first end. to the second end of the transitional portion 28, see FIGURE 7. A portion of each fold 38 near the second end of the transitional portion 28 is threaded with at least one thread 42. A portion of each projection 40 near the second end of the transitional portion 28 is threaded with at least one thread 42. The threads 42 in the folds 38 and in the projections 40 run in alignment with each other and with the gears 34 formed in the body 26 as the threads 34, 42 are formed in the body 26 and in
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the projections 40 of the transitional portion 28 in a conventional thread roll forming operation as described herein. Only the portions of the folds 38 and the projections 40 having the same diameter as the root thread 34 is screwed into the body 26. The thread 42 formed in the folds 38 and in the projections 40 is continuous for a predetermined distance until the respective folds 38 have a height that is lower than the root thread 34 in the body 26. In each of the first and second embodiments, the drive head 24 has a means for coupling or an external configuration that is defined by a first series of sections 46 and a second series of sections 48 that alternate around the circumference thereof. That is, by driving the path around the circumference of the driving head 24, a section 46 is found, then there is the section 48, then there is the section 46, then there is the section 48, and so on around the circumference of the drive head 24. The first series of sections 46 and the second series of sections 48 extend in the axial direction along the length of the drive head 24. Each section 46 as shown in the drawings, takes the form of an unthreaded bend 46 formed from a curved surfacewhich is directed radially into the central line 36 of the insulator 22 and which is generated by an ellipse. The center of each ellipse that is used to form the respective folds 46 is radially equidistant from the center line 36 of the fastener 22. Each section 48, as shown in the drawings, takes the form of an unthreaded projection 48 formed from a surface curved radially outwardly from the central line 36 of the insurer 22 and generated by an ellipse. The center of each ellipse that is used to form the respective protrusions 48 is radially equidistant from the center line 36 of the belay 22. As such, the folds 46 are depressed toward the center line 36 of the belay 22 relative to the projections 48. adjacent curved surfaces forming the respective folds 46 and projections 48 generally arise generally, tangentially and smoothly to each other. The configuration of the alternating folds 46 and projections 48 define the external configuration of the drive head 24. The folds 46 and projections 48 are equally spaced around the circumference of the drive head 24 and in the illustrated embodiment, six folds 46 are provide in the first series and six outlets are provided in the second series. The centers of the ellipses used to form the folds 46 define a circle with respect to the center line 36 of the insurer 22
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and the centers of the ellipses used to form the projections 48 define a circle with respect to the center line 36 of the insurer 22. These circles may overlap each other or may be in imbalance with each other. Specifications of the geometry of the folds 26 and the projections 48 as provided on the drive head 24 are described in U.S. Patent Nos. 5,207,132 and 5,279,190, each of which is commonly owned by the current assignee and whose description of each one of the two is incorporated herein by reference. Each fold 46 in the drive head 24 is axially aligned with a respective fold 38 in the transitional portion 28. Each projection 48 on the drive head 24 is axially aligned with a respective projection 40 in the transitional portion 28. The aligned folds axially 46 and projections 48 in the drive head 24 and folds 38 and projections 40 in the transitional portion 28 are dimensioned to avoid interference with a nut 50 positioned and engaged with the threads 42 or 44 in the transitional portion 28 and in the body 26. The plug 32 in the drive tool 30 is complementary to, but not completely identical to, the drive head 24 and the transitional portion 28 of the fastener 22 and thus
.- 1 ac ac al de se 24 ef the folds in plug 3 must be dimensioned for a clear fit. Likewise, in order to achieve the desired coupling engagement at depth of engagement between the projections and coupling folds, the shape of the plug 32 should be altered slightly so that the projections 40 are received within the folds in the coupling. plug 32 to a specific extension and respectively the projections of the plug 32 are received within the folds 38 of the fastener 22, in order to achieve a desired depth of engagement between the respective projections and folds. When the drive head 24 and the transitional portion 28 engage within the socket 32, the effective cross-sectional area of the network and the last torsional strength are increased by changing the location of the potential fracture to the transitional portion 28 as a result of the extension of the means 42 and the projections 48 of the driving head 24 along the portion
transitional 28 thereby forming the folds 38 and the projections 40. The engagement of the transitional portion 28 within the socket 32 provides a greater coupling between the fastener 22 and the plug 32 on which the structures of the prior art are provided. Also, the provision of the folds 38 and the projections 40 in the transverse portion 28 provide a horizontal loading component. In this aspect, when the end load is applied to the drive head 24 and the transitional portion 28 by the drive tool 30, a portion of the end carriage is applied to the transitional portion 28 by converting the end load to a horizontal vector component. As such, the coupling results along the sides of the axially aligned projections and folds of the drive head 24 and in the plug 32, and the forces are applied to the fold root in the transitional portion 28 defining a component of horizontal vector. To form the belay 22 according to the first or second embodiments of the invention, the transitional portion 28 and the drive head 24 are formed in the body 26. Next, a generally flat screw die is used to form the threads 34, 42 or 44, (depending on what mode is being formed) in the same according to the teaching of the thread roller
known The threads 42 or 44 s ^ 1 partially form in the transitional portion 38 as a result of the thread roll die and the thread forming grooves therein that extend into the transitional portion 28. The threads 42 or 44 formed in the transitional portion 28 have a root diameter that is slightly greater than the ridge of protrusion 48 of the axially aligned projections 48 of the drive head 24. Only the portions of the folds 38 and the projections 40 having the same diameter as threaded the root thread 34 in the body 26. The attention is now directed to FIGURE 9 which illustrates the third embodiment of the invention. In this embodiment, the axially extending drive head 24 is eliminated. The transitional portion 28 is formed at the free end of the body 26 and transitions directly into the body 26. Any modality of the transitional portion 28 may be provided in this embodiment. The unthreaded plug (not shown) in the drive tool (not shown) d in a complementary, though not totally identical, manner to the transitional portion 28 of the fastener 22 and this "shape" engages therewith so that the The drive tool 30 can impart the driving forces to the belay 22. To form the belay 22 according to the third embodiment of the invention, the transitional portion 28 is formed in the body 26. Subsequently, a die of the thread roller is generally plane is used to form the threads 42 or 44 (depending on which mode is being formed) therein according to the known thread roll teaching.The threads 42 or 44 are partially formed in the transitional portion 38 as a result of the die of the thread roll and the thread forming groove therein extending in, the transitional portion 28. Only the portions of the folds 38 and the projections 40 that they have the same diameter as the root thread 34 is screwed into the body 26. As will be recognized by one skilled in the art, the present invention is not limited to a protrusion design. Any coupling configuration provided in the drive head 24 may extend in the transitional portion 28. A hexagon, a frame may be provided for example. Although preferred embodiments of the present invention are shown and described, it is envisioned that those skilled in the art can devise various modifications of the present invention without departing from the spirit and scope of the appended claims.