Torsion tool with pull rope

Abstract

A tool for twisting a rotatable element has a first bit and an opposing second bit, and a housing. The first and second bits are rotationally fixed relative to each other and rotatable relative to the housing. The tool includes a third fixed bit fixed relative to the housing. The first and second bearing assemblies are operably connected with a one-way bearing assembly having a wrap cord partially exposed from the housing. A user may operate the first and second bits by pulling the cord such that the bearing assembly and the first and second bits rotate in a common absolute direction. The first bit may be connected to an element to rotate the element in a first mounting direction when the cord extends, and the second bit may be connected to the element to rotate the element in an opposite second mounting direction when the cord extends.

Description

[0001] Cross - reference to related applications

[0002] This application claims priority to U.S. Provisional Patent Application No. 63 / 626,161, filed on January 29, 2024, the entire content of which is incorporated herein by reference in its entirety. Technical field

[0003] The disclosed embodiments relate to tools, and more particularly to torsion tools or wrenches for driving, removing, and / or adjusting drivable elements. The tool can be specifically configured for installing, removing, and adjusting tension rods in a drum. Background art

[0004] "Drum tuning" is the process of adjusting the tension of a drum to adjust its sound properties. For example, a player can tune a drum to remove unwanted overtones and / or produce a desired sound and response. Additionally, some drums (such as timpani and rototoms) are tuned to a specific pitch. Drums are typically tuned by tightening or loosening tension rods or cords that control the tension on the drum head. A tension rod is an elongated threaded fastener held by a nut, and the shape of its head is adapted to be received by a torsion tool, which is known in the art as a drum key. Most commonly, the tension rod has a cube or rectangular prism shape at its exposed upper end, and the drum key has a socket at one end with a very corresponding shape.

[0005] Standard drum keys have a T - shape and carry an elongated axially - extending bit that bears the socket at the distal end and has a laterally - extending cross - member at the opposite end for twisting about the axis of the bit to twist the engaged tension rod. Traditionally, applying high torque required a standard drum key with a 6 - inch cross - member, which, due to its bulky shape and size, made it a stationary tool (non - portable). On the other hand, any smaller and more portable traditional stationary drum key was not suitable for applying high torque because the length of the cross - member had to be shorter. Drum keys with a one - way ratchet mechanism (similar to a ratchet wrench) have been developed with the aim of increasing efficiency; however, each tension rod still had to be turned manually.

[0006] Installing tension rods and tuning a drum using these types of tools can be a long and cumbersome process due to the need for multiple hand rotations. To speed up the process of installing tension rods, tuning bits that work with power tools (such as drills) have been developed. However, these power tools are necessarily powerful and crude installation devices that lack the ability to finely adjust the tension rod to "fine - tune" the acoustic properties of the drum. Power - driven tools also provide too much torsion, resulting in the stripping of the tension rod threads or damage to the drum hardware.

[0007] Accordingly, a drum key that provides improved installation speed and efficiency under high torque conditions while maintaining the ability to fine-tune the tension rod would be useful. SUMMARY OF THE INVENTION

[0008] In one embodiment, a tool for twisting a drivable element has a first bit, a one-way bearing assembly, and a cord. The first bit is configured to engage the drivable element. The one-way bearing assembly is operably connected to the first bit, and the cord is wound around the one-way bearing assembly. Forcing the cord to unwind causes the bearing and the first bit to rotate in a first direction.

[0009] In another embodiment, a tool for twisting a drivable element has a frame, a first bit, and a second bit, each bit being rotatable relative to the frame. The first bit has a first engagement profile configured to engage the drivable element. The second bit extends opposite the first bit and has an engagement profile configured to engage the drivable element. The first bit and the second bit are rotationally fixed relative to each other. The tool further includes a third bit that is rotationally fixed relative to the frame and has an engagement profile configured to engage the drivable element. The one-way bearing assembly is operably connected to the first bit and the second bit, and the cord is wound around it, with one end of the cord protruding from the frame. Forcing the cord to unwind by a human action causes the bearing, the first bit, and the second bit to rotate in a first direction while the third bit does not rotate.

[0010] In yet another embodiment, a drum key for twisting a tension rod in a percussion instrument has a first twisting bit extending axially and a second twisting bit extending coaxially with the first twisting bit. Each of the first twisting bit and the second twisting bit has a sleeve configured to engage an end of the tension rod. The second twisting bit is rotationally locked to the first twisting bit. The one-way bearing assembly is operably connected to the first bit and the second bit. The cord is wound around the one-way bearing assembly, and one end of the cord is accessible to a user. Forcing the cord to unwind to an extended position causes the bearing, the first twisting bit, and the second twisting bit to rotate in a first absolute direction. Releasing the cord from the extended position causes the bearing to rotate in a second absolute direction opposite the first absolute direction and wind the cord. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 An embodiment of the disclosed twisting tool in the form of a drum key is shown in perspective;

[0012] Figure 2 is Figure 1 a side view of the tool;

[0013] Figure 3 is Figure 1 a front view of the tool;

[0014] Figure 4 is Figure 1 an exploded view of a tool;

[0015] Figure 5 is a cross-sectional view of the disclosed tool;

[0016] Figure 6 shows the disclosed tool having a first rotatable bit engaged with a rotatable element;

[0017] Figure 7 shows the disclosed tool having a fixed bit engaged with a rotatable element;

[0018] Figure 8A shows an exemplary drum with a tension rod that can be installed and removed with the disclosed tool;

[0019] Figure 8B is Figure 8A an enlarged view of the drum portion of, which shows the tension rod;

[0020] Figures 9A - 9B shows an alternative embodiment of a torsion tool having a torsion limit protection mechanism;

[0021] Figures 10A - 10C shows alternative embodiments of a torsion tool having different torsion limit protection mechanisms; and

[0022] Figures 11A - 11B shows alternative embodiments of a torsion tool having different torsion limit protection mechanisms. Detailed Description

[0023] Among the benefits and improvements disclosed herein, other objects and advantages of the disclosed embodiments will become apparent from the following, wherein, in all the drawings, the same numbers represent the same parts. The present invention discloses a detailed embodiment of a torsion tool having a pull cord, which can take the form of a drum key; however, it should be understood that the disclosed embodiments are merely illustrative of the present invention, and the present invention can be implemented in various forms. In addition, each example given in connection with the various embodiments of the present invention is illustrative, not restrictive.

[0024] Throughout the specification and claims, unless the context clearly dictates otherwise, the following terms have the meanings expressly associated herein. The phrase "in some embodiments" used herein does not necessarily refer to the same embodiment (although it may). The phrases "in another embodiment" and "in some other embodiments" used herein do not necessarily refer to different embodiments (although it may). Thus, as described below, various embodiments can be readily combined without departing from the scope or scheme of the present invention.

[0025] As used herein, unless the context clearly indicates otherwise, "based on" is not exclusive and allows for additional factors not expressly described.

[0026] In addition, as used herein, unless the context clearly indicates otherwise, the term "or" is equivalent to the term "and / or". Unless otherwise expressly indicated in the context, the term "based on" is not exclusive and allows for additional factors not described. Further, throughout the specification, the meanings of "a", "an", and "the" include the plural. The meaning of "in" includes "in" and "on".

[0027] In addition, the terms "substantially", "substantially the same", "similar", "similarly", "like", "approximately", "approximate", and any combination thereof mean that the difference between the compared features or characteristics is less than 25% of the corresponding value / measure used to measure and / or define the compared features or characteristics.

[0028] Unless the context dictates otherwise, all ranges recited herein include their endpoints, and open ranges include only commercially practical values. Similarly, unless the context indicates otherwise, all lists of numerical values include intermediate values. The recitation of numerical ranges herein is merely a shorthand method of referring individually to each separate numerical value that falls within the range. Thus, unless otherwise stated herein, each individual value of a range is incorporated into the specification as if it were individually recited herein. The use of any and all examples, or exemplary language (e.g., "such as") provided herein for certain embodiments of the present invention is merely intended to better illustrate the subject matter of the present invention and is not a limitation on the scope of the subject matter of the present invention, which may otherwise be described and claimed.

[0029] The grouping of alternative elements or embodiments of the subject matter of the present invention disclosed herein should not be construed as a limitation. Each member of the group can be individually recited and claimed, or combined in any combination with other members of the group or other elements found herein. For convenience and / or patentability reasons, one or more members of the group can be included in or deleted from the group. When any such inclusion or deletion occurs, the specification is hereby considered to include the modified group, thereby satisfying the written description of all Markush groups used in the appended claims.

[0030] Refer to Figures 1 - 5, which shows a non - limiting preferred embodiment of the twisting tool 10. The tool generally includes opposing rotary drive bits 16 and 18, and a fixed bit 14 that is generally perpendicular to the rotary drive bits 16a and 18. The fixed bit 14 is held in a relative position by a central housing or frame 12. In the described embodiment, the tool 10 is in the form of a drum key, and each bit 14, 16, and 18 respectively has a sleeve 30, 32, 34 of a common shape. The sleeves 30, 32, 34 are sized and shaped to engage the rectangular prism top ends of the tension rods. The exact dimensions and structures of the sleeves in the preferred embodiment are non - limiting, as the inventive concept embodied in the twisting tool 10 is applicable to sleeves of any shape and size. In other embodiments, one or more bits are detachable and can be replaced with bits having different sleeves.

[0031] The rotary bits form part of a rotary key assembly with a one - way bearing unit 20. The bearing unit 20 is operatively engaged with each rotary bit 16 and 18. As Figure 5 shown in the cross - section of, the rotary bits 16 and 18 can be formed as a single integral unit; however, such a construction is not necessary. The bearing unit 20 is configured to rotate freely relative to the rotary bits 16 and 18 in a first direction and to be rotationally locked relative to the rotary bits in an opposite second direction. When the bearing unit rotates in the second direction, this arrangement will rotationally drive the bits 16 and 18 and allow the bearing to rotate freely in the first direction without causing the bits to rotate.

[0032] As will be explained in more detail below, and as Figure 5 shown, the bearing assembly includes an internal torsion spring 38 under tension, which provides a rotational biasing force in the first direction in which the bearing can rotate freely. The rotary bits 16 and 18 rotate independently of the housing 12, and the fixed bit 14 is rotationally fixed relative to the housing 12. In the shown non - limiting embodiment, the fixed bit 14 is fixed to the housing by a fixing screw 36. The housing 12 may also include an end cap surrounding one or more bits, as indicated by reference numeral 28. The end cap 28 mainly provides improved aesthetics and contributes to the comfortable ergonomics of the user. The housing 12 may also be formed by a plurality of sub - components 12a and 12b connected together around the rotary key assembly 20.

[0033] As Figure 4 and Figure 5 shown, the bearing unit 20 is driven by a pull - cord assembly that includes a cord 22 that is wound around an outer spindle housing or shell 23 and an outer knob 24 of the bearing assembly 20. The cord 22 extends through a hole 26 in the drum key housing 12, and the knob 24 is attached to the outer cord end to be exposed and accessible to the user.

[0034] In this particular embodiment, the bearing unit 20 utilizes a one-way needle bearing 29. However, there are other embodiments that utilize other similar one-way rotation systems, such as replacing the needle bearing with a clutch or a one-way ratchet bearing.

[0035] The rotary bits 16 and 18 are rotationally locked to each other and are rotationally locked relative to the inner bearing unit spindle 23 in one direction (the aforementioned second direction) via the needle bearing. This allows the spindle 23 to freely rotate relative to the bits 16 and 18 in the opposite direction (the aforementioned first direction). When the cord 22 is pulled out from the housing 12 and unwound from the bearing unit 20, the needle bearing 29 locks, causing the bits 16 and 18 to rotate in a common absolute direction, and the bearing assembly housing is driven by the unwinding of the cord. When the user releases the extended cord 22, the cord retracts into the housing under the force of the spring 38 while allowing the needles of the bearing to rotate freely, such that the bits 16 and 18 do not rotate in the reverse direction with the bearing unit 20. This rewinds the cord around the spindle 23.

[0036] Figure 8A An exemplary drum 50 with a tension rod 52 is shown, where the tension rod 52 is used to adjust the tension in the membrane 58, which is stretched across the ring 54 that is mounted on a generally cylindrical frame 56. Figure 8B An enlarged view of the drum portion is shown, and the tension rod 52 engaged with the ring 54 holding the membrane is shown. As those familiar with the musical instrument and percussion instrument industries will understand, the tension rod 52 is twisted to adjust the tension in the membrane 52, where tightening the tension rod 52 increases the tension in the membrane and unwinding the tension rod 52 reduces the tension in the membrane.

[0037] In the case of the drum key, the cord-driven bits 16 and 18 greatly improve the installation and unloading efficiency of the tension rod 50 similar to a power tool, but without the same level of power and thus without the risk of damaging the drum hardware. The engagement of the first rotary bit 16 with the tension rod 50 is shown in Figure 6 (it should be noted that other drum hardware is omitted for clarity).

[0038] Furthermore, as Figure 7 shown, while ensuring better torsional sensitivity, the user can engage the fixed bit 14 with the tension rod 50 and rotate the tension rod 50, which is the convention for a fixed drum key. When the fixed bit 14 is engaged, the vertical end cap 28 and / or portions of the rotary bits 16 and 18 are used by the user as lever lateral members to provide torsional force. The fixed bit 14 is typically engaged after the tension rod 50 is installed with the rotary bit 16 to fine-tune the acoustic characteristics of the drum and can also be used to initially unwind or start unloading a tension rod that may be stuck.

[0039] To install the tension rod 50, the user can engage the first batch head 16 with the tension rod and then grasp the knob and pull the cord. Pulling the cord causes the drive bit 16 to rotate and drive the tension rod in the installation direction (usually clockwise). Once the user releases the cord, the cord retracts into the housing 12 without causing the bit 16 to rotate, so the tension rod does not turn back in the opposite direction. This process can be repeated as many times as needed. Thereafter, the user can optionally use the fixed bit 14 to finely twist the tension rod.

[0040] To uninstall the tension rod, the user simply engages the opposite rotating bit 18 and pulls the cord 22, causing the tension rod to rotate in the opposite direction (usually counterclockwise). It should be noted that the first rotating bit 16 and the second rotating bit 18 are rotationally locked relative to each other such that when the cord is pulled, they rotate in the same absolute direction as the bearing unit 20. This enables rotation in the opposite installation direction when the second rotating bit 18 engages the element (opposite to when the first rotating bit 16 engages the element).

[0041] Figure 9A and Figure 9B An embodiment of a torsion tool 100 is depicted, which includes a torsion limiting protection mechanism 160 to prevent the cord 122 from accidentally breaking under excessive tension. In this embodiment, the protection mechanism 160 includes one or more balls 162, and the associated spring 164 radially biases the balls 162 inwardly so that the balls 162 are received within an outer mandrel or housing 123. In this embodiment, the bearing unit 120 includes a housing 121 that has a series of circumferentially spaced ribs 125, and the ribs 125 are molded with a plurality of spaced ribs (or bumps) 125 facing the outer mandrel 123. Each set of adjacent ribs 125 is spaced apart by a groove 127, and the groove 127 is sized and shaped to receive a portion of the outer surface of the inwardly biased ball 162. In one embodiment, the ribs 125 and the grooves 127 are configured to extend perpendicular to a portion of the housing 121 of the bearing unit 120, however, this is not limiting.

[0042] The protection mechanism 160 is configured with a specially adjusted spring force, size, and surface profile such that the balls 162 fit within the grooves and maintain a quasi-locked engagement, thereby tensioning the cord 122 by pulling with torsion within a predetermined "safe" range to rotate the rotating bits 116 and 118 (as in the previous embodiments). However, if the tension applied to the cord 122 exceeds a predetermined threshold, the bearing unit 120 will slide as the balls 162 are radially pressed outward against the force of the spring 164 under pressure from the ribs 125. This prevents the cord 122 from breaking under excessive tension, which is typically caused by the user using the cord 122 to twist a drive that is jammed or already fully installed hardware.

[0043] Figures 10A - 10C Depicts another embodiment of a twisting tool 200 having a different twist limit protection mechanism 260. The protection mechanism 260 of this embodiment operates according to a mechanical principle similar to that of the mechanism 160 of the tool 100 described in the previous paragraph. In this embodiment, the protection mechanism 260 includes a plurality of fingers 262 molded into the outer mandrel 123, and each finger 260 has a bump or protrusion 264 extending radially inward. The bearing unit 220 is formed with a housing 221, which is similar in form to the housing 121 of the previous embodiment and has circumferentially spaced ribs and grooves. The protection mechanism 260 is configured such that the bump 264 of each finger 262 is received within the groove between the ribs of the housing 221. When the rope 222 is tensioned by pulling with a force within a predetermined "safe" range, the bump 264 is held within the groove in a quasi-locking engagement to allow the bearing to rotate the rotary bits 116 and 118. When the twisting force exceeds a predetermined threshold, the bearing unit 220 slides by the radially outwardly bent fingers 262 to disengage the bump 264 from the groove of the housing 221, thereby allowing the bearing to slide and the rope to extend to prevent it from breaking under excessive tension.

[0044] Figures 11A - 11B Shows yet another embodiment of a twisting tool 300 having a different twist limit protection device 360. In this embodiment, the outer mandrel 323 is molded with one or more inwardly opening grooves 364, and the one or more inwardly opening grooves 364 receive an elastic O-ring 262. In the depicted embodiment, at least a portion of the groove 264 opens into the region inside the mandrel 323 such that the O-ring contacts the outer surface of the housing 321 of the bearing unit 320. This embodiment includes two O-rings, however this is not restrictive. Additionally, referring to Figure 10B each groove 364 in the mandrel 323 opens at three locations, generally represented by the straighter portions of a generally triangular O-ring 362. In this embodiment, the O-ring frictionally engages the outer surface of the bearing housing 321 such that when the rope 322 is pulled with a force within a predetermined "safe" range, it rotates the bearing and the associated bits 316 and 318. However, when a predetermined twisting force is exceeded, this force overcomes the frictional force between the O-ring 362 and the housing 321 to allow the bearing to slide and the rope to extend, thereby preventing the rope from breaking under inappropriate tension.

[0045] In Figures 9A - 9B 、 Figures 10A - 10C and Figures 11A - 11B elements identical to those of the first embodiment of the twisting tool 10 are identified with reference numerals having the same trailing two digits after "1", "2", or "3" for reference and context understanding. For example, Figures 9A - 9BThe key components of the torsion tool 100 therein include: a tool housing 112, a fixed bit 114, a first rotating bit 116, a second rotating bit 118, a bearing unit 120, and an internal torsion spring 138. Figures 10A - 10C The key components of the torsion tool 200 therein include: a tool housing 212, a fixed bit 214, a first rotating bit 216, a second rotating bit 218, a bearing unit 220, and an internal torsion spring 238. Figures 11A - 11B The key components of the torsion tool 300 therein include: a tool housing 312, a fixed bit 314, a first rotating bit 316, a second rotating bit 318, a bearing unit 320, and an internal torsion spring 338.

[0046] The specific description of the tools 10 / 100 / 200 / 300 and the disclosed embodiments are unique drum keys having bits 14 / 114 / 214 / 314, 16 / 116 / 216 / 316, 18 / 118 / 218 / 318, the bits having engagement profiles (i.e., sleeves 30 / 130 / 230 / 330, 32 / 132 / 232 / 332, and 34 / 134 / 234) sized and shaped to engage with the tension rods 52 of the drum 50. However, those skilled in the art will readily understand that the torsion tool 10 is not limited to this particular preferred embodiment and / or limited to bits having these engagement profiles. There are additional embodiments of the torsion tool that embody the inventive features of a pull cord drive with one or more bits having one-way bearings, the one-way bearings being reversible and / or may include a separate fixed bit. For example, many other tools not shown have bits that have corresponding engagement profiles for twisting other rotatable elements. Additionally, there are embodiments having removable and replaceable drive bits for engaging various different rotatable drive elements (e.g., screws, bolts, nuts, etc.).

[0047] Although the preferred embodiments have been set forth for purposes of illustration, the foregoing description should not be regarded as a limitation of the invention. Accordingly, various modifications, adaptations, and alternative designs will be apparent to those skilled in the art without departing from the spirit and scope of the invention as claimed.

Claims

1. A tool for twisting a drivable element, comprising: A first set of bits, the first set of bits being configured to engage with the drivable element; A one-way bearing assembly, the one-way bearing assembly being operably connected to the first set of bits; And A rope, the rope being wound around the one-way bearing assembly; wherein, Forcing the rope to unwind causes the bearing and the first set of bits to rotate in a first direction.

2. The tool according to claim 1, comprising a second set of tool heads opposite the first set of tool heads, the second set of tool heads being operatively connected to the bearing assembly, wherein, Forcing the rope to unwind causes the bearing and the second set of bits to rotate in the first direction.

3. The tool according to claim 2, wherein, Engage the first set of bits with the drivable element and force the rope to unwind so that the first set of bits drives the drivable element in a first mounting direction.

4. The tool according to claim 3, wherein Engage the second set of bits with the drivable element and force the rope to unwind so that the second set of bits drives the drivable element in an opposite second unloading direction.

5. The tool according to claim 1, including a third bit configured to engage with a drivable element, wherein, The third set of bits is rigid relative to the first set of bits and is not operably engaged with the bearing assembly.

6. The tool according to claim 5, wherein, The fixed bit extends substantially perpendicular to the first set of bits.

7. The tool according to claim 2, comprising a third bit configured to engage a drivable element, wherein, The third set of bits is rigid relative to the first and second sets of bits and is not operably engaged with the bearing assembly.

8. The tool according to claim 7, wherein The fixed bit extends substantially perpendicular to the first and second sets of bits.

9. The tool according to claim 8, wherein, The tool is a drum key, and each bit includes a sleeve, the size and shape of the sleeve being adapted to engage the tension rod of the drum.

10. The tool according to claim 1, wherein, The tool is a drum key, and the first set of bits includes a sleeve, the size and shape of the sleeve being adapted to engage the tension rod of the drum.

11. The tool according to claim 1, wherein, The one-way bearing assembly includes a needle bearing, a ratchet bearing, and other gear ratchet mechanisms.

12. The tool according to claim 1, wherein, The one-way bearing assembly is a needle bearing.

13. The tool according to claim 1, wherein The first set of bits includes a sleeve that defines a generally rectangular prism shape.

14. The tool according to claim 7, wherein At least one of the first, second, and third sets of bits is removable and can be replaced with a replacement bit having a different sleeve profile.

15. The tool according to claim 1, comprising a twist limit protection unit configured to remain engaged with the bearing unit to rotate the bearing unit and the first set of bits when the rope is forced to unwind with a twisting force below a predetermined threshold, and to disengage from the bearing unit when the rope is forced to unwind with a twisting force above the predetermined threshold.

16. A tool for twisting a drivable element, comprising: A frame; A first set of bits, the first set of bits having an engagement profile configured to engage with the drivable element and being rotatable relative to the frame; A second set of bits, the second set of bits extending opposite to the first set of bits and having an engagement profile configured to engage with the drivable element, the second set of bits being rotationally fixed relative to the first set of bits and rotatable relative to the frame; A third set of bits, the third set of bits being rotationally fixed relative to the frame and having an engagement profile configured to engage with the drivable element; A one-way bearing assembly, the one-way bearing assembly being operably connected to the first and second sets of bits; And A rope, the rope being wound around the one-way bearing assembly, and one end of the rope protruding from the frame, wherein, The rope is forcibly unwound by a human action so that the bearing, the first set of heads, and the second set of heads rotate in a first direction, while the third set of heads does not rotate.

17. The tool according to claim 16, wherein, Each of the first set of heads, the second set of heads, and the third set of heads has a sleeve with substantially the same shape and size.

18. The tool according to claim 16, wherein, The third set of heads extends in a direction substantially perpendicular to the first set of heads and the second set of heads.

19. The tool according to claim 16, wherein At least one of the first set of heads, the second set of heads, and the third set of heads is detachable and can be replaced with a replacement set of heads having a different engagement profile.

20. A drum key for twisting a tension rod in a percussion instrument, comprising: A first twisting set of heads having a sleeve configured to engage an end of a tension rod extending in a first axial direction; A second twisting set of heads having a sleeve configured to engage an end of a coaxial tension rod, and the second twisting set of heads extends coaxially with the first twisting set of heads, and the second twisting set of heads is rotationally locked to the first twisting set of heads; A one-way bearing assembly operably connected to the first set of heads and the second set of heads; And A rope wound around the one-way bearing assembly, one end of the rope being accessible to a user, wherein The rope is forcibly unwound to an extended position by a human action so that the bearing, the first twisting set of heads, and the second twisting set of heads rotate in a first absolute direction, and The rope is released from the extended position so that the bearing rotates in a second absolute direction opposite to the first absolute direction, and the rope is wound without rotating the first twisting set of heads or the second twisting set of heads.

21. The drum key according to claim 19 further includes a third torsion bit extending perpendicular to the first torsion bit and the second torsion bit, wherein, The third twisting set of heads rotates independently of the first twisting set of heads and the second twisting set of heads.

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