TECHNICAL AREA

The present invention concerns a torsional measuring device (also known as a mounting tool) in order to be able to determine exactly the centre of rotation, and/or for the setting of an angle between a first and a second threaded rod according to claim 1 and a method for the setting of an angle between a first and a second threaded rod with the aid of a torsional measuring device according to claim 6.

The invention relates to the manufacturing industry for lifts and linear screw arrangements with threaded tracks for the operation of lifts or other industrial applications. The invention, however, is not limited to lifts, and can also relate to trapezoidal threaded rods, screw rods, spindle rods, etc., that are used in a large number of industrial segments and fields of use and for means of transport.

BACKGROUND

Sections of threaded rods are currently mounted one onto another to form a long threaded rod with one or several threaded tracks. Each section of threaded rod comprises at one of its ends a female part (a hole) with a thread and at its second end a male part (a peg) with a corresponding thread. A first section of threaded rod is thus joined to a second section of threaded rod through screwing the two parts together. It is important that the sections of threaded rod come into the correct positions relative to each other such that the threaded track or tracks do not form a disjoint or a step at the joint after the rods have been screwed together (mounted). In order to ensure that the starting points of the threaded track of the joined sections of threaded rod face each other and form an even transition, the first section of threaded rod is provided with a pre-determined mark that is to coincide with a mark at the second section of threaded rod.

In order to adjust the relative angle of rotation between the sections of threaded rod such that the marks coincide with each other to ensure an even transition between the starting points of the threaded tracks, mounting personnel currently use, for example, pipe wrenches to tighten the screw joints such that the marks coincide with each other.

SUMMARY OF THE INVENTION

It is one purpose, safely and in a manner that saves time, to mount sections of threaded rod to each other, which sections of threaded rod extend in a longitudinal axial direction along a central axis, while at the same time the starting points of the two mounted screwed rods face each other, while at the same time a pre-determined prestress between the male part and the female part is achieved at the screw joint.

A further purpose is to be able simply to rotate a first section of threaded rod relative to a second section of threaded rod such that the angle between them is correct.

One purpose is to secure the mounting of a first section of threaded rod to a second section of threaded rod against rotation.

A further purpose is to be able, with exact precision, to join two sections of threaded rod, each of which demonstrates at least one starting point of the thread at the relevant external surface of the section of threaded rod.

A further purpose is that it should be possible for mounting personnel to be able to mount a screw joint in dim light and with poor visual contact with the screw joint.

A further purpose is to avoid damage to the threads of the sections of threaded rod during their alignment and mounting. One purpose is also to develop prior art technology within the field.

At least one of the above purposes has been achieved with the aid of the torsional measuring device defined in the introduction to the description, characterised by the characterising part that is specified in claim 1.

It is appropriate that the torsional measuring device be a combined torsional measuring device and mounting device.

It is preferable that the first lever part constitute an integral part of the first torsional device.

It is appropriate that the first adjustment element comprise an extended first screw comprising a first grip that can be gripped by a human hand, which first screw interacts not only with the second torsional device, but also with the first lever part such that, on rotation of the first grip, the first and second torsional devices can be rotated relative to each other in order to set the angle between them.

It is preferable that the first grip be provided with a plus symbol.

In this way, mounting personnel can note the number of revolutions the first grip is rotated in order to achieve a mutual clockwise rotation of the sections of threaded rod. It is appropriate that the first adjustment element be set such that it achieves a tensile force, and prevented from achieving a pressure force, such that the first adjustment element can be manoeuvred to achieve a rotational movement for the first torsional device clockwise relative to the second torsional device. The first torsional device can in this way be rotated relative to the second torsional device around the said central axis, and simple operation of the torsional measuring device for mounting personnel is in this way achieved with the aid of the lever part.

In this way, a tool has been achieved that is simple to use for mounting personnel while at the same time providing an exact alignment of the screw joint of the first and second threaded rods. With the aid of the exact alignment, a pre-determined prestress is achieved at the screw joint.

It is preferable that the sections of threaded rod extend in a longitudinal axial direction along a central axis.

It is preferable that the first section of threaded rod be provided with a joint end that demonstrates a mounting peg (male part) that extends in the direction of the central axis, which mounting peg is provided with an external thread.

It is appropriate that the second section of threaded rod be provided with a joint end that demonstrates a mounting hole (female part) that extends in the direction of the central axis, which mounting hole demonstrates internally a thread that corresponds to the mounting peg.

It is preferable that the mounting peg be provided with a first transverse hole (a male part hole) that extends transverse to the said central axis.

It is preferable that a part at one end of the second section of threaded rod, that forms the said mounting hole, be provided with second and third transverse holes (female part holes), which are, in turn, set to line up with each other. The said second and third transverse holes extend transverse to the said central axis and form the said female part holes, which are intersected in the transverse direction by the said mounting hole.

It is preferable that the said mounting peg and said mounting holes, comprising threads that are matched to each other, and the said first, second and third transverse holes be so specified that, during mounting and adjustment of the angle between the sections of threaded rod, a standard prestress is achieved in the screw joint while at the same time an exact alignment is achieved. It is appropriate that the said sections of threaded rod be provided with at least one threaded track (for example a trapezoidal thread).

In this way, the joint end of the threaded track of the section of threaded rod demonstrates a starting point that is to be adapted into an initial track of the corresponding joined threaded rod. It is preferable that the position of the said starting point at the relevant section of threaded rod be pre-determined during manufacture of the section of threaded rod such that the relevant starting point of the thread is turned to face the starting point of the thread that fits it. At the same time, the designs of assembly pegs (with external thread) and assembly holes (with internal thread) are predetermined during manufacture of the sections of threaded rod, the threaded tracks of which demonstrate positions of starting points and gradients of thread in such a manner that the said starting points of threads (at the periphery of the sections of threaded rod) come into position when the mounting has been completed at the correct position relative to each other, and a predetermined level of prestress is achieved. At the same time, the insertion of the first, second and third transverse holes at the male part and the female part is pre-determined during manufacture of the sections of threaded rod, which holes are to be aligned with each other when the said mounting has been completed.

In this way the end of the joint of the section of threaded rod demonstrates several threaded tracks with several starting points, which are to be turned to face several starting points of the

corresponding threaded rod that is to be joined on, with high accuracy. It is preferable that a second adjustment element be arranged in a manner that allows coupling between a lever part arranged at the second torsional device and the first torsional device.

In this way, the second torsional device can be rotated relative to the first torsional device around the said longitudinal axis, and with the aid of the lever part simple operation for mounting personnel is achieved. It is appropriate that the second adjustment element comprise an extended second screw comprising a second grip that can be gripped by a human hand, which second screw interacts not only with the first torsional device, but also with the second lever part such that the first and second torsional devices can be rotated relative to each other during rotation of the second grip in order to achieve a correct angular setting. It is preferable that the second grip be provided with a minus symbol. In this way, mounting personnel can note the number of revolutions the second grip is rotated in order to achieve a mutual anticlockwise rotation of the sections of threaded rod.

For example, in the case in which the mounting personnel rotated the first grip with its plus symbol four revolutions, the second grip is to be rotated two revolutions (half of the number of revolutions of the first grip).

It is appropriate that the second adjustment element be set such that it achieves a tensile force, and prevented from achieving a pressure force, such that the second adjustment element can be manoeuvred to achieve a rotational movement for the first torsional device anticlockwise relative to the second torsional device. It is preferable that the said first adjustment element comprise a first screw in interaction with the second torsional device.

It is appropriate that the torsional measuring device comprise a measuring rod in order to set the angle between a male part hole at the said first threaded rod and a female part hole at the said second threaded rod. It is in this way ensured that the starting points for the threaded tracks at the jointed sections of threaded rod come into the correct position relative to each other and face each other, and form an even transition.

It is preferable that the male part and female part be provided with one (or at least two) matching mutually transverse (transverse to the central axis) penetrating holes (at the male part and the female part) that are aligned with each other.

It is in this way achieved with the aid of the fact that the penetrating transverse hole of the male part and the two penetrating transverse holes of the female part are aligned with each other that the screw joint between two sections of threaded rod is tightened to a pre-determined prestress.

It is in this way achieved that a pre-determined prestress in the screw joint is present when the mounting has been completed, independent of the tolerance setting at the said penetrating transverse holes. This is ensured through the fact that the penetrating and transverse holes are aligned with each other.

It is appropriate that pins are inserted into the penetrating and transverse holes in order to prevent the screw joint rotating. It is preferable that the pins demonstrate deformations after being inserted that lock the pins at the sections of threaded rod.

It is appropriate that a deformation zone be achieved during the insertion operation on the surface of the securing pins in the border area between the mounting peg and the mounting hole. A permanent joint is in this way achieved that is secure against undesired rotation of the sections of threaded rod thread relative to each other.

This has been solved also with the aid of a method for the setting of a relative angle between a first and a second section of threaded rod with the aid of a torsional measuring device, which is during use in interaction with the said first and second sections of threaded rod, in which each one of first and second torsional devices arranged at the torsional measuring device comprises a first and a second grip for the attachment in a manner that allows removal at the said first and second sections of threaded rod mounted to each other, a first lever part at the first torsional device can be coupled with the second torsional device by means of a first adjustment element, the method comprises the steps to: bring the said first section of threaded rod into interaction with the first grip; bring the said second section of threaded rod into interaction with the second grip; insert a measuring rod with a first diameter through a first male part hole that is transverse with a second diameter at the said first section of threaded rod and a transverse first female part hole at the said second section of threaded rod; rotate, in a first mutual direction of rotation, the said first and second torsional devices with a first relative angle where the inserted measuring rod prevents further rotation; rotate the said first and second torsional devices in a second mutual direction of rotation opposite to and with half of the magnitude of the said first mutual direction of rotation.

The said transverse first female part hole comprises the previously described second and third transverse holes that extend transverse to the said central axis. The first female part hole is intersected in the transverse direction by the said mounting holes. As an alternative, an initial oblique position is achieved through a measuring rod comprising a first part with a truncated conical tip and a second part demonstrating a constant diameter being introduced into the first transverse hole and partially into the first set of transverse holes.

The end of the truncated conical tip can, for example, come to be positioned within the area of the central axis or at an appropriate distance from the central axis. It is preferable that the first part demonstrate a smaller diameter than the second part. It is preferable that the first diameter of the measuring rod (at the second part of the measuring rod) be smaller than the second diameter of the transverse holes.

It is appropriate that the first female part hole demonstrate a third diameter that corresponds to the second diameter or that differs from the second diameter. In this way, a method has been achieved that ensures the correct joining between two threaded rods such that the male part hole and the female part holes coincide in alignment with each other.

In this way, a simple operation for the connection of two threaded rods is achieved at the same time as starting points for the threads of the threaded rods come to be correctly positioned relative to each other and a pre-determined prestress is achieved in the screw joint.

It is appropriate that the measuring rod demonstrate a first part that becomes more narrow in a conical manner in a direction away from a second part arranged at the measuring rod, which second part has a constant (cylindrical) first diameter.

It is preferable that the method comprise, before the step of inserting the measuring rod, the step to rotate the said first and second threaded rods such that the said first male part hole and the first female part hole form a penetration that demonstrates a diameter that is smaller than the diameter of the measuring rod (smaller than the diameter of the second part and larger than the end of the first part end, and/or smaller than the diameter of an appropriate cross-section of the first part).

The measuring rod will in this way be stopped, which means a partial insertion of the measuring rod, whereby the said rotation of the first mutual direction of rotation from an initial position will start at an exact initial position. This is possible since the position when the measuring rod is allowed from its partial insertion to be able to be pushed fully through the male part hole and the female part hole - two female part holes surrounding and aligned with the male part hole - at its second part will be noted by the mounting personnel.

It is preferable that the step to rotate the threaded rods (with the aid of the torsional devices) comprise, in a first mutual direction of rotation forming a first relative angle (from the initial position to the position at which the inserted measuring rod prevents further rotation of the first section of threaded rod relative to the second section of threaded rod), that the initial position comprise the said partial insertion of the measuring rod. It is appropriate that the method comprise the subsequent step to, when the first transverse male part hole and the first female part hole are aligned with each other, insert a first pin through these in order to secure the mounting from rotation. It is in this way achieved that locking of the screw joint is ensured.

It is preferable that the method comprise the step to insert a second pin through a second transverse male part hole and second transverse female part hole aligned with each other. It is appropriate that the diameter relationship between a second measuring rod and the relevant second male part hole and female part hole, coincide, in the same manner as for the first male part hole and the second female part hole relative to the first measuring rod.

A double locking is in this way achieved, which promotes safety during, for example, the operation of personnel lifts.

It is appropriate that the said first mutual direction of rotation is clockwise.

It is preferable that the said second mutual direction of rotation is anti-clockwise.

In order to ensure that the starting points of the threaded tracks of the joined sections of threaded rod face each other and form an even transition, the male and female parts are provided with one or several transverse penetrating holes that are to be aligned with each other. When the said penetrating transverse holes of the relevant male and female parts are aligned with each other, the screw joint between two sections of threaded rod is tightened to a pre-determined prestress.

In order to be able to achieve a pre-determined prestress in the screw joint, independent of the tolerance setting of the said penetrating holes, therefore, the penetrating holes must be aligned with each other. The pins are inserted into the holes in order to prevent the screw joint from rotating, whereby a deformation zone is achieved on the surface of the securing pins in the border area between the mounting peg and the mounting hole. A permanent joint is in this way achieved that is secure against undesired rotation.

SUMMARY OF DRAWINGS The invention will now be explained with reference to the drawing, of which schematically: Figure la shows three sections of threaded screw for joining; Figure lb shows a joined threaded screw for a lift;

Figure 2a shows a joint end with a male part and a joint end with a female part; Figure 2b shows in a first view from the side the joint ends in Figure 2a joined; Figure 2c shows in a second view from the side the joint ends in Figure 2a joined; Figure 2d shows a cross-section of a screw joint; Figure 3 shows a joint end with several starts of threads;

Figures 4a-4d show an example of a method to determine a common centre line for penetrating holes at male and female parts;

Figure 5a shows an example of a torsional measuring device in a view from the side;

Figure 5b shows the torsional measuring device in Figure 5a in a view from above;

Figure 6 shows an example of the torsional measuring device in a view from above;

Figures 7a-7c show an example of a method to set the angle of rotation between the penetrating holes at a first and a second section of threaded screw;

Figures 8a-8b each show one example of a grip for a torsional measuring device; and

Figure 9 shows an example of a method for the setting of a relative angle of rotation.

DETAILED DESCRIPTION OF EMBODIMENTS The invention will now be explained with the aid of examples. Items may be present in the schematic drawings that show the same type of item, but in different drawings with the same reference numbers. The drawings are not to be interpreted strictly, and details that do not have significance for the invention have been omitted from them, for reasons of clarity.

Figure la shows three sections of threaded screw 1', 1", 1"' to be joined. A first section of threaded screw comprises a first joint end 3' demonstrating a first male part 5' and a second joint end 3" demonstrating a first female part 7'. Also a second section of threaded screw 1" comprises a first joint end 3' demonstrating a second male part 5" and a second joint end 3" demonstrating a second female part 7".

Figure lb shows a joined threaded screw 1 for the driving of a lift cage 9. The threaded screw 1 is fixed mounted at its upper end 10 and freely suspended at its lower end 11. Figure 2a shows a first joint end 3' with a male part 5 and a second joint end 3" with a female part 7 at the relevant section of threaded screw 1', 1" in Figure la extending along a central axis CA. The external surface of the sections of threaded screw 1', 1" is arranged with a set of trapezoidal threads 13. The male part 5 comprises a threaded mounting peg 15. The female part 7 comprises a threaded mounting hole 17, whose gradient corresponds to that of the mounting peg 15. First 19' and second 19" transverse holes are arranged at the mounting peg 15. The female part 7 comprises on both sides of the mounting hole 17 a first set of holes 21' comprising two penetrations 22' aligned with each other and on the two sides of the mounting hole 17 (when viewed in the transverse direction relative to the central axis CA). The female part 7 comprises on both sides of the mounting hole 17 a second set of holes 21" comprising two penetrations 22" aligned with each other and on the two sides of the mounting hole 17 (when viewed in the transverse direction relative to the central axis

CA). The first transverse hole 19' is taken up into the mounting peg 15 in such a manner that it comes to a position aligned with the first set of holes 21' of the female part 7 with such an orientation that the starting point of each trapezoidal thread 13 of the first joint end 3' comes to the correct position in front of starting point of the corresponding trapezoidal thread 13 of the second joint end 3", which orientation of the first transverse hole 19' and the first set of holes 21' (aligned with each other) determines also a pre-determined prestress at the mounted screw joint. The threaded mounting peg 15 and the corresponding threaded mounting hole 17 demonstrate such starting points of the threads that the said first transverse hole 19' and the first set of holes 21' come to be aligned with each other. The second transverse hole 19" and the second set of holes 21" are defined in a corresponding manner. In other words, the second transverse hole 19" and the second set of holes 21" extend parallel to the first transverse hole 19' and the first set of holes 21'. Figure 2b shows in a view from the side that the joint ends 3', 3" in Figure 2a have been rotated into a position for securing. The first 19' and the second 19" transverse holes and the first 21' and the second 21" sets of holes are in the correct positions relative to each other. Figure 2c shows the joint ends 3', 3" in a view from the side, in which view the section A-A has been taken. Figure 2d shows the section A-A in Figure 2c. A first pin 25' is inserted into the first transverse hole 19' and the first set of holes 21', whereby a bulge that locks the screw joint (not shown in the drawings) forms in the border area between the mounting peg 15 and the mounting hole 17. A second pin (not shown in the drawings) is inserted in a similar manner through the second transverse hole and the second set of holes. Figure 3 shows a joint end 3 with several starts of threads 26. Such a joint end 3 with several starts of threads 26 requires extreme accuracy in the relative angular setting of a first and a second section of threaded screw, such that corresponding starts of threads 26 come into position in front of each other. Figures 4a-4d show an example of a method to determine a common centre line CL (see, for example, Figure 4d) for transverse and penetrating holes 19, 21 (set of holes) at male and female parts. Figure 4a shows how the first and the second 1" sections of threaded screw (see, for example Figure la) have been united by rotation by mounting personnel (not shown in the drawings) in a first step using hand power. The sections of threaded screw 1', 1" have been united by rotation through the relevant mounting peg 15 (comprising an external thread) and mounting hole 17

(comprising an inner thread) to such an extent that the first transverse hole 19 (of the mounting peg 15) and the first set of holes 21 (of the mounting hole 17) are positioned obliquely (initial oblique positioning) and not aligned with each other. A second transverse hole and a second set of holes demonstrate similar orientation as the first transverse hole 19 and the first set of holes 21 relative to the central axis CA, but are obscured in the drawing. A torsional measuring device 41 according to one embodiment (shown in, for example, Figure 5a) is mounted around the first and the second sections of threaded screw 1', 1". It is preferable that the said initial oblique position is achieved in such a manner that when a measuring rod 27, comprising a first part 31 with a truncated conical tip and a second part 29 demonstrating a constant diameter, is introduced into the first transverse hole 19 and partially into the first set of transverse holes 21 (after mounting of the torsional device) then the end of the truncated conical tip will come to be positioned within the area of the central axis CA. The first part 31 demonstrates a smaller diameter than the diameter of the second part of the measuring rod 27. Figure 4b shows how the first and the second 1" sections of threaded screw are rotated such that the measuring rod 27 completely falls in such that the second part 29 of the measuring rod 27 can be enclosed within the first transverse hole 19 and the first set of holes 21. The condition shown in Figure 4b is in this respect denoted as an "initial condition" UL or "starting condition". The first and the second 1" sections of threaded screw are now further rotated together until the measuring rod 27 comes to a stop (at the stopped condition SL) and is in contact across contact points KP of the first transverse hole 19 and the first set of holes 21, as is shown in Figure 4c. The mounting personnel thus rotates the first and the second 1" sections of threaded screw from the initial condition UL to the said stopped condition SL clockwise in a first direction of rotation V 1 and notes a first relative angle of rotation a. The mounting personnel can, if this is desired, remove in a subsequent step the measuring rod 27 from the first transverse hole 19 and the first set of holes 21. The torsional measuring device is now manoeuvred such that the first and the second 1" sections of threaded screw are rotated in a second direction of rotation VR2 that is opposite to the first direction of rotation VR1 by a second relative angle of rotation β, which has half of the magnitude of the first relative angle of rotation a. Since the torsional measuring device is manoeuvred to rotate the first and the second 1" sections of threaded screw in the second direction of rotation VR2 with half of the magnitude of the angle of the first relative angle of rotation a to a final position SP, in which the said first transverse hole 19 and the first set of holes 21 come to be aligned with each other. In this way a definition of a hole pattern has been achieved in which the transverse hole 19 and the set of holes 21 form the common centre line CL. In a next step, the mounting personnel inserts pins (not shown in the drawings) through the first transverse hole 19 and the first set of holes 21 and through the second transverse hole and the second set of holes. When the two pins are inserted, deformations are automatically formed at an edge region of the relevant first and second transverse holes 19, 21, which deformations permanently fix the screw joint in its correct condition.

Figures 5a-5b show an example of a torsional measuring device 41. The torsional measuring device 41 is shown from the side in Figure 5a. The torsional measuring device 41 is arranged for the setting of relative angles (when viewed in the radial direction) between first and second sections of threaded screw 1', 1". The torsional measuring device 41 is arranged to be brought during use into interaction with the said first and second 1" sections of threaded screw. Figure 5b shows first 43' and second 43" torsional devices that can be coupled with each other through screws 45. The first and second torsional devices 43', 43" each comprise first and second grips 45', 45" for the attachment in a manner that allows them to be removed (clamping) at the said first and second sections of threaded screw 1', 1" with the aid of the said screws 45. A first lever part 47' at the first torsional device 43' can be coupled with the second torsional device 43" by means of a first adjustment element 49', in the form of a first screw 51'. It is preferable that the second torsional device 43" comprise a second lever part 47". A second adjustment element 49" in the form of a second screw 51" is arranged in a manner that allows coupling between the second lever part 47" at the first torsional device 43'. The torsional measuring device 41 comprises a measuring rod 27 in order to set the relative angle between a transverse male part hole 19" at the said first section of threaded screw and a set of female part holes 21"' at the said second section of threaded screw 1". The first screw 51' comprises an extended first screw comprising a first grip 53' arranged such that it can be gripped by a human hand and provided with a plus symbol. The second screw 51" comprises a second grip 53" arranged such that it can be gripped by a human hand and provided with a minus symbol.

Figure 6 shows an example of the torsional measuring device 42 in a view from above. The torsional measuring device 42 in Figure 6 is arranged for the setting of the relative angle between first and second 1" sections of threaded screw (see Figure la), which torsional measuring device 42 is during use in interaction with the said first and second sections of threaded rod , 1", in which first and second torsional devices 44', 44" arranged at the torsional measuring device 42 each comprise a first and a second grip 46', 46" for attachment in a manner that allows removal at the said first and second sections of threaded screw. A first lever part 48' at the first torsional device 44' can be coupled with the second torsional device 44" by means of a first adjustment element 50'.

Figures 7a-7c show an example of a method to set a suggested torsional measuring device 42 at the desired angle. This example of a method for the setting of a relative angle between a first and a second section of threaded screw and is carried out, for example, with the aid of the torsional measuring device 42 in Figure 6 or the torsional measuring device 41 in Figure 5a. The torsional measuring device 42 is in interaction during use with the said first and second sections of threaded screw 1', 1". A first torsional device 44' and a second torsional device 44" (partially obscured) each comprise a first grip 46' and a second grip (obscured) for attachment in a manner that allows them to be removed at the said first and second sections of threaded screw. A first lever part 48' at the first torsional device 44' can be coupled with the second torsional device 44" by means of the first adjustment element 50' shown in Figure 6. The method comprises the steps: to bring the said first section of threaded screw into interaction with the first grip 46', subsequently to bring the said second section of threaded screw into interaction with the second grip and to insert a measuring rod 27 with a first diameter through a transverse first male part hole 18 with a second diameter at the said first section of threaded screw 1' and a transverse first female part hole 20 at the said second section of threaded screw 1". The said first and second torsional devices 44', 44" are subsequently rotated to a first relative angle VI at which the inserted measuring rod 27 prevents further rotation. The said first and second torsional devices 44', 44" are subsequently rotated to a second relative angle of rotation V2 that is opposite to and has half of the magnitude of the said first relative angle of rotation VI.

Figures 8a-8b each show one example of a grip 45 at a torsional measuring device according to a pair of further examples. The grip 45 in Figure 8a demonstrates a smooth surface. The smooth surface is compressed against the threaded outer surface 61 of the threaded screw. A fixed grip is achieved at the same time that the outer surface of the thread 61 is protected from damage. The grip 45 in Figure 8b demonstrates a grip surface 59 with protrusions 63. The grip surface 59 and the protrusions 63 are brought into interaction with the thread of the threaded screw. A fixed grip is achieved at the same time that the outer surface of the thread 61 is protected from damage. Figure 9 shows a method for the setting of a relative angle between a first and a second section of threaded screw rod with the aid of a torsional measuring device according to any one of the preferred examples described here. Step 101 shows the start of the method. Step 102 shows the following: to bring the said first section of threaded rod into interaction with the first grip; to bring the said second section of threaded rod into interaction with the second grip; to insert a measuring rod with a first diameter through a transverse first male part hole with a second diameter at the said first section of threaded rod and a transverse first female part hole at the said second section of threaded rod; to rotate, in a first relative angle of rotation, the said first and second torsional devices to a first relative angle, at which the inserted measuring rod prevents further rotation; to rotate the said first and second torsional devices to a second relative angle of rotation opposite to and with half of the magnitude of the said first relative angle of rotation. Step 103 shows the stop of the method.

The invention is not to be seen as limited by the examples described above: within the framework of the invention other embodiments are also encompassed, which describe in the same way the innovative concept or combinations of the examples that have been described.