The present invention refers to a locking device and particular to a nut to be engaged with a bolt in a rapid way with desired clamping force.

Background

Traditional fastening devices can comprise a screw or a bolt with external threads and a nut with internal threads, where the nut is threaded on to the bolt and screwed onwards until a desired attachment is achieved. A screw is mostly used to secure or fasten things or to attach an object to for example a wall, where the screw is attached directly into the material/article. A bolt and a nut is most often used to fasten a stack of parts together, where the bolt is brought through a hole in the article and the nut is thereafter threaded onto the body of the bolt to secure the article between the bolt head and the nut. The bolt and the nut are kept together by a combination of their threads friction, a slight stretch of the bolt and compression of the parts.

The traditionally used screws as well as bolts and nuts have a number of potential problems. For example, if the bolt is long it can take a long time to thread the nut from the bottom of the bolt towards the head of the bolt to fasten the article. It can also be hard to thread the nut onto the bolt if the space where the bolt and nut is to be used is limited. Furthermore, the nut has a tendency to unthread when it is exposed to stress or vibrations or the bolt can break. Temperature differences can possibly also affect the threading.

The problem that it takes a long time to thread a nut onto a long bolt has for example been addressed by WO2014/088600. WO2014/088600 describes a rapid-engaging, positive locking machine screw mechanism comprising a screw, wherein the body of the screw comprises male threads and at least one longitudinal segment devoid of threads. The application further describes a work piece which defines a hole having female threads for receiving the screw and at least one longitudinal segment devoid of threads. The longitudi- nal screw segment devoid of male threads and the longitudinal hole segment devoid of female threads are arranged such that the screw body is longitudinally received in the hole without engagement of the male screw threads with the female work piece threads. The male and female threads engage upon rotation of the screw with respect to the mating threaded work piece. The screw and the work piece are also provided with a locking feature and a mating locking feature, respectively. The locking feature comprises a boss and the mating locking feature comprises a recess to receive the boss. The locking features limit the rotation of the threaded sections to a maximum of one-half of a rotation.

Problems still arising with the screw mechanism according to WO2014/088600 is that it has threads and it requires a boss and a recess to receive the boss. Threads are subjected to loosening over time, which WO2014/088600 has solved by using a boss and a recess. However, the use of the boss and recess is more complicated to manufacture.

Another solution to the problem that it takes a long time to thread a nut onto a long bolt, and also addressing the problem of loosening over time, has been described in

WO2016/080888. WO2016/080888 describes a fastening device comprising a stem part and a locking part both provided with segments with substantially flat surfaces, making it possible to move the locking part along the axis of the stem part without having to screw any of the parts. To avoid problems with unthreading and loss due to vibration, one of the parts are provided with an axial segment of flanges and the other with axial segments of projections. At least one of the parts is rotatable in relation to the other to bring the flanges and projections in and out of engagement with each other.

Problems still arising with the mechanism according to WO2016/080888 are that it is not possible to keep turning one of the parts to achieve a required torque and/or clamping effect.

Still another solution to the problem that it takes a long time to thread a nut onto a long bolt and addressing both the problem of loosening over time and the problem with achieving a required torque or clamping effect has been described in PCT/SE2017/050082 wherein a locking device is described, which locking device comprises two parts, which can be identical. The two parts are turnable relative each other and are both provided with segments with substantially flat surfaces, making it possible to move the locking part along the axis of the stem part without having to screw any of the parts and are also provided with limiting means that limits the relative turning of the two parts, which makes it possible to keep turning the locking device after the two parts have been put together to achieve a required torque and/or clamping effect.

Another solution to the problem that it takes a long time to thread a nut onto a long bolt is a SN Series Nut, provided by Pentair pic. The SN Series Nut is a three part nut which can be positioned on a threaded rod on any location and save time by not having to screw it along the whole rod. The nut can be opened by twisting the nut half a rotation of an axle.

Problems still arising with the mechanism according to the SN Series Nut is that it is not possible to easy adjust the position of the nut when it has been positioned, since the user would either have to keep screwing until the desired position has been reached or twist and open the nut to move it to another location and then twist to fasten it again.

The present invention however, solves the same problems as has been addressed in PCT/2017/050082. Another example has been shown in US 3,878,757 where an automatic locking sliding nut is described, which requires a locking means having a nut-locking member to work. A locking device as described in this application only comprises one part, which is easier for the user and also cheaper to manufacture.

There are also a few other types of sliding nuts presented before, but they all demands more than one part and that is mainly because they are all invented for a specific use or purpose. For example GB 2402965 which whows a quick-release nut used in a security lock for a window, in US 5,558,481 which shows a self-locking nut for use in quick clsing clamps, in FR 2941504 which shows a locking nut having a built in lock washer and also in DE8506747U which shows an anchor nut.

According to one aspect of the present invention, a locking device is described, which locking device acts a nut. The locking device comprises a cylindrical axially extending through hole and is in circumferential direction provided with at least one internal axial segment comprising at least one thread. The locking device further comprises either at least one internal axial segment having a substantially flat surface or at least one internal axial segment having a surface with reduced height of at least one thread. The axial center line of the cylindrically extending through hole is inclined in relation to the main axis of the locking device. The locking device according to the present invention is mirror shaped.

Another aspect of the invention is a fastening device comprising at least two connecting parts, one stem part 100 and one locking device, wherein the stem part and the locking device are arranged to engage with each other by connecting the locking device onto the stem part along a main longitudinal direction of the stem part from a distal end towards a proximate end and wherein the locking device is a locking device as described in this description.

In the following, the invention will be described in detail, with reference to exemplifying embodiments of the invention and to the enclosed drawings, in which:

Fig. 1 shows a front view of the locking device in a sliding position

Fig. 2A shows a front view of the locking device in a mounting position

Fig. 2B shows a back view of the locking device in a mounting position

Fig. 3A shows a front view of the locking device

Fig. 3B shows the locking device from a front view in a cross sectional view

Fig. 4A shows the arrangement of threads in a regular nut as seen in a longitudinal section

Fig. 4B-D shows three different arrangements of threads as seen in a longitudinal section

Fig. 5 shows a perspective view of the fastening device with the locking device in a sliding position

Fig. 6 shows a perspective view of the fastening device with the locking device in a mounting position

For the purpose of this description and claims the main axis A is defined as the vertical axis going through the center of the locking device, as shown in Fig. 3B and 5A, and the main axis C is defined as the vertical axis going through the center of the stem part as shown in Fig. 5A. The axial center line B of the locking device is defined as the axial center line if the through hole, as shown in Fig. 3B and 5B. The terms "upwards", "downwards", "vertical" and any derivatives thereof relate to the invention as oriented in Figs. 5 and 6. Furthermore, a substantially flat surface is defined to be either a radially curved surface or a flat surface without any threads, such surfaces can be seen in Fig. 3. The threads are curved radially along the axial direction of the stem part and the locking device.

Referring to Figs.1-3 a locking device in accordance with the present invention consists of one part, which part is provided with at least one thread on at least one internal segment and at least one segment with substantially flat surface. It is also possible to have a locking device which is provided with one internal segment comprising threads of regular height and one internal segment comprising threads of a reduced height. Fig. 4A-D shows different exemplified arrangement of threads. The locking device can in turn be connected to and engage with a stem part 100 and together form a fastening device, shown in Fig. 5 and 6, for the purpose of securing an article (not shown) between the stem part and the locking device, or between the locking device and any other part or device that can be used on the stem part.

Fig. 1 shows the locking device 1, in the form of a nut, from the front in a sliding position. The sliding position is defined to be the position where the locking device 1 can be connected to and translated along a main axis from a distal end towards a proximate end of a stem part 100. In order to be able to more easily translate the locking device along a main axis of a stem part, the locking device is tilted so that the axis of the cylindrically extending through hole 2 is inclined in relation to the axis direction of the locking device, this can also be seen in Fig. 5. It is also possible to rotate the locking device 1 like a regular nut to move it upwards and downwards along the axis of a stem part 100, this will however take more time and effort than to tilt the locking device 1 and to slide the it along the axis of the stem part 100.

Fig. 2 A shows a locking device 1, in the form of a nut, from the front in a mounting position. This view is referred to as the front view or the front side. The locking device 1 comprises a cylindrical axially extending through hole 2. In Fig. 2A and B, the cylindrical axially extending through hole 2 is shown by a darker circular formation covering the cylindrical axially extending through hole 2. Fig.2B shows the same locking device 1, rotated 180 degrees to show the back of the same locking device 1 with the same darker circular formation covering the same cylindrical axially extending through hole 2. This view is referred to as the back view or the back side. The darker formation is used to show that the cylindrical axially extending through hole 2 is eccentrically located in relation to the main axis A of the locking device. The axial center line B of the locking device 1, in the sliding position, in relation to the main axis A of the stem part is shown in Fig. 5.

The mounting position is defined to be the position wherein the locking device 1 can be rotated along an axis direction of a stem part 100, as can be seen in Fig. 6. In a mounting position, either the front side of the locking device or the back side of the locking device can be attached to the stem part 100 first. The front side and the back side of the locking device works in the same way and has the same appearance.

Fig.2A and 2B together shows the shifting (or tilting) of the locking device 1 which, together with the appearance of at least one internal segment comprising at least one thread and at least one internal segment having a substantially flat surface, gives this nut the advantage that it is possible to transport it along the axis of a stem part 100 and then to tilt up the locking device 1 to a position that is parallel to the stem part 100 to bring the at least one thread 3 in the locking device 1 in contact with the threads 103 on the stem part 100. When the locking device 1 is in the mounting position it can be rotated around the axis of the stem part 100 as a regular nut.

Fig. 3A shows a front view of the locking device in a position where it has been slightly rotated around its own axis, to show the at least one internal segment with at least one thread 3 and the at least one internal segment having a substantially flat surface. As can be seen in Fig. 3A the at least one thread is on a part of the inside of the locking device in an upper position 3', and in another part of the inside of the locking device, the at least one thread is in a lower position 3". When the at least one thread is in an upper position 3', the lower position below the thread is an internal segment having a substantially flat surface 4". When the at least one thread is in a lower position 3", the upper position above the at least one thread 3" is an internal segment having a substantially flat surface 4'. In one embodiment, half of the inner circumference of the locking device is provided with at least one thread in an upper position 3' and the other half of the inner circumference of the same locking device is provided with at least one thread in a lower position 3". It could also be possible to divide the inner circumferential so that there is more than one segment having at least one thread in the upper part and more than one segment having at least one thread in the lower part, depending on the appearance of the stem part 100 to be used together with the locking device 1.

Fig. 3B shows a cross section of one possible embodiment of the locking device 1. In this embodiment, the locking device 1 is provided with two internal segments having a substantially flat surface 4',4" and two internal segments comprising threads 3', 3". Fig. 3B also shows the axial center line B of the through hole 2 in relation to the main axis A of the locking device 1. The axial center line B has the same inclination as the through hole 2, and will hence be different in different embodiments, which is described in more detail below.

Fig. 4A shows an arrangement as in a regular nut, where all threads have the same height. Fig. 4B-D shows three different arrangements of threads as seen in a longitudinal section. It should however be noted that also other arrangements of threads can be used within the scope of the claims.

Fig.4B shows an embodiment according to the present invention, wherein the locking device 1 is in circumferential direction provided with at least one internal axial segment comprising threads 3 and at least one internal axial segment having a substantially flat surface 4.

Fig. 4C shows an alternative embodiment of the present invention, wherein the locking device 1 is provided with at least one internal segment with at least one thread 3 and at least one internal axial segment having a surface with reduced height of at least one thread 5. The substantially flat surface 4 or the reduced height of the at least one thread 5 is necessary to be able to incline or tilt the locking device 1 in relation to a stem part 100 (not shown in Fig. 4A-D), when the locking device 1 is attached to a stem part 100, as shown in Fig. 5-6. The reduced height of the at least one thread 5 is dependent on the inclination of cylindrically extending hole 2 in relation to the main axis direction of the locking device 2. A large inclination requires a thread with a very low height, while a smaller inclination makes it possible to have a larger thread height.

Fig. 4D shows a further alternative embodiment of the present invention, wherein the locking device 1 is provided with at least one internal segment with at least one thread 3 and at least one internal axial segment having a surface with reduced height of more than one thread 5, wherein the threads 5 have a gradually decreasing height towards the end of the locking device 1. The gradually reduced height of the threads 5 is dependent on the inclination of cylindrically extending hole 2 in relation to the axis direction of the locking device. A large inclination requires a thread 5 with a very low height, while a smaller inclination makes it possible to have a higher thread height 5. In one embodiment of the present invention, the locking device 1 is in circumferential direction provided with at least two axial segments comprising at least one thread 3 and at least two axial segments comprising a substantially flat surface 4. In this embodiment, the first axial segment comprising at least one thread 3' is provided over a surface covering an upper part of one half of the inner circumference of the locking device 1 and the second axial segment comprising at least one thread 3" is provided over a surface covering a lower part of the other half of the inner circumference of the locking device 1. The first axial segment comprising a substantially flat surface 4" is provided below said first axial segment comprising at least one thread 3', and the second axial segment comprising a substantially flat surface 4' is provided above said second axial segment comprising at least one thread 3".

A further embodiment of the present invention (not shown) is a locking device which is in circumferential direction provided with at least two axial segments comprising at least one thread 3 and at least two axial segments having a surface with reduced height of at least one thread 5. In this embodiment, the first axial segment comprising at least one thread 3' is provided over a surface covering an upper part of one half of the inner circumference of the locking device 1 and the second axial segment comprising at least one thread 3" is provided over a surface covering a lower part of the other half of the inner circumference of the locking device 1. The first axial segment having a surface with reduced height of at least one thread 5 is provided below said first axial segment comprising at least one thread 3', and the second axial segment having a surface with reduced height of at least one thread 5 is provided above said second axial segment comprising at least one thread 3".

A common feature for all embodiments of the present invention is that the internal of the locking device looks the same in both ends, i.e. it is mirror shaped. The locking device 1 is mirror shaped around a plane going through its lengthwise center, i.e. the front view of the locking device looks the same as the back view of the locking device. Mirror shaped is intended describe that the locking device looks and works the same when look at from front view and from the back view. It works in the same matter irrespective of which end that is connected first.

An advantage of the use of a locking device according to the invention is a rapid locking mechanism with the additional feature that the torque and/or clamping effect can be adjusted by a user.

As can be seen from the figures in this description, the external surface of the locking device preferably has an essentially continuous surface, especially it can have a shape of a hexagonal nut. This has the advantage that any tool adapted to be used with hexagonal surfaces can be used to further rotate the locking device, when connected on a stem part 100, to further adapt the torque and/or clamping effect. It is also possible to have another external surface of the locking device. A common feature, not depending on the external surface, is that the locking device is a device that can be used without any other special parts or special tools needed. It can be used in any application that uses a regular nut. Fig. 5 shows a fastening device comprising a stem part 100 and a locking device 1, which locking device is in a sliding position where it can be transported along the axis of the stem part. The locking device 1 can be attached to the stem part 100 either with the front end first or with the back end first.

The sliding position is defined to be a position wherein the locking device 1 is tilted in relation to the stem part 100, i.e. the axis of the cylindrically extending hole 2 is inclined in relation to the axis direction of the locking device, which can be seen in fig.3B and 5. The inclination of the axial center line B of the cylindrically extending through hole 2 in relation to the main axis direction A of the locking device 1 is 0,5- 89 degrees.

Fig. 5 shows that the main axis C of the stem part 100 and the axial center line B of the through hole 2 of the locking device 1 essentially coincides when the locking device 2 is in a sliding position. Fig. 5 also shows the relation between the main axis A of the locking device and the main axis C of the stem part when the locking device is in a sliding position.

When the locking device is in a sliding position, the at least one internal axial segment comprising at least one thread 3 is situated in the direction of the inclination of the axis, i.e. the locking device are inclined so that the threads 3 are tilted away from the stem part 100 and the internal axial segment comprising a substantially flat surface 4 or the surface having at least one thread of reduced height 5 are closest to the stem part 100, making it possible to slide the locking device 1 along the axis of the stem part 100, without the threads 3 being in contact with the stem part 100.

The stem part 100 is in circumferential direction provided with external threads 103. The stem part 100 can either be a threaded rod, a screw, a bolt or any other part which is in circumferential direction provided with external threads 103.

The stem part 100 could also be a stem part which comprises at least one axial segment comprising threads 103 and at least one axial segment with substantially flat surface 104. The stem part 100 and the locking device 1 are arranged to engage with each other by connecting the locking device onto the stem part 100 along a main longitudinal direction of the stem part 100 from a distal end towards a proximate end. In order to attach the locking device 1 to the stem part 100, the locking device 1 should be positioned so that the locking device 1 is tilted. The locking device can then be connected to and translated along the main axis from a distal end towards a proximate end of the stem part 100, until a desired position is achieved. When a desired position is achieved, the locking device 1 is tilted up to a position where it is perpendicular to the axis of the stem part, as shown in fig.5. The locking device can then be rotated to adjust the momentum and/or clamping effect, if needed.

Fig. 6 shows the fastening device, wherein the locking device is in a mounting position, i.e. it is not tilted and the threads 3 on the locking device 1 will engage with the threads 103 on the stem part 100, when the locking device 1 is rotated around the axis of the stem part 100.

The fastening device according to the present invention comprises at least two connecting parts, one stem part 100 and one locking device 1, wherein the stem part 100 and the locking device 1 are arranged to engage with each other by connecting the locking device onto the stem part 100 along a main longitudinal direction of the stem part 100 from a distal end towards an proximate end and wherein the locking device is as described above.

When the locking device is in a sliding position, the axial segments having substantially flat surface makes it possible to translate the locking device along the axis of the stem part. This is achieved by having a substantially flat surface in the "upper part" of the inner circumferential of the locking device and a second substantially flat surface in the "lower part" on the opposite side of the inner circumferential.

To separate the locking device from the stem part 100, the locking device 1 can either be rotated around the stem part, like a regular nut, or can be tilted again to the sliding posi- tion for a faster disassembly of the parts. When in a sliding position it is possible to translate the locking device 1 along the axis of the stem part 100 to either remove it from the stem part 100 or to change the position of the locking device 1 on the stem part 100.

When the locking device 1 is in a mounting position, as shown in fig. 6, it is possible to rotate the locking device 1 around the stem part 100 as a regular nut. If needed a tool can be used to rotate the locking device 1 on the stem part 100. Any tool that can be used to hold and rotate either the stem part or the locking device can be used for this purpose, for example a wrench.

A further advantage of the locking device 1 is that it looks the same internally in both ends, meaning that it does not matter which end that is attached to the stem part first. This is an advantage for the user, who does not need to know which end to attach first to a stem part. It is also an advantage during production since it is easier to produce a locking device that are supposed to have the same characteristics and appearance in both ends.

It is a further advantage that the locking device according to the present invention is not dependent on an unbroken thread on the stem part 100. During cutting of the threaded rod, it is quite common that the threads are, at least partially, damaged. Since the locking device according to the present invention is attached to the stem part 100 in a sliding/ tilted position, a broken thread is not a problem. If the stem part comprises a broken thread in the end where the locking device is to be attached, the locking device can be rotated so that one of the internal axial segments having a substantially flat surface is positioned where the broken thread is.

The fastening device can further comprise a third part, for example a resilient part (not shown) arranged between the proximate end of the stem part 100 and the locking device 1, in the case where the stem part is a bolt, or between the locking device and any other device placed on a rod to achieve a better clamping effect, if needed. The resilient part is provided with a hole to connect the resilient part to the stem part 100. The resilient part can be added from the bottom of the body of the stem part 100 and upwards towards the head to the stem part 100. The function of the resilient part is to give a resilient function which will give a tighter fit between the locking device and the article to be fastened through which the locking device is added.

The resilient third part is arranged to apply a spring force against the stem part 100 along the main longitudinal direction of the stem part 100 towards the distal end and against and/or to apply a spring force against the locking device along said main longitudinal direction.

The resilient part can either be a separate part or attached to the stem part 100 or attached to the locking device 1. The resilient third part can for example be a rubber packing, an elastic washer or the like. It could also be for example a cylinder head gasket for an engine. The resilient part is exchangeable/replaceable so that the stiffness can be adapted to the specific use.

Above, an exemplified preferred embodiment has been described. However, it is realized that the invention can be varied without departing from the basic idea of the invention.

The locking device is preferably a nut, wherein it is preferable that at least one of the first and second part has the shape of a hexagonal nut. It is however possible to have other outer shapes of the nut as well, such as a wing nut, a captive nut, a threaded sleeve or any other type of nut/sleeve which has the ability to engage with the stem part 100, provided that the locking device can be provided with segments comprising threads and segments comprising substantially flat surfaces. The locking device could for example be integrated in a cap, a pipe or any other application. The function of the locking device can be migrated into a welded nut or in any other parts in a manufacturing line.

The stem part 100 can further be integrated in for example a sheet metal, a pipe, a plastic cap or any other type of material suitable for integration with a bolt or a screw. The term "thread" or "threads" as used in this document are meant to mean any kind of three-dimensional helical structure intended to transform a rotating movement to a linear movement. The threads can for example be metrical threads, English threads, pipe threads, trapezoidal threads or any other type of threads. The type of threads are preferably adapted to the intended use of the locking device 1 and the stem part 100, respectively. It is also possible that the locking device 1 is provided with one type of threads and the stem part 100 is provided with another type of threads.

The pitch, i.e. the threads per axial distance, can have the same or different values for the locking device 1 and the stem part 100. The stem part 100 can for example be provided with threads 103 with a larger pitch (fewer threads per axial distance) and the locking device 1 can be provided with threads 3',3", 5 with a smaller pitch (more threads per axial distance), or the stem part 100 can be provided with threads 103 having a smaller pitch and the locking device 1 can be provided with threads 3',3", 5 having a larger pitch.

It is also an advantage that the locking device according to the present invention does not need any extra parts to function. This makes it easier for the user and easier and less expensive to produce as compared to previous products on the market which requires more parts or special tools to be used.

The first part land the stem part 100 can be made of any type of metal, plastic, rubber or any other type of material suitable for production of screws and nuts, as well as combinations of different materials. The first part land the stem part 100 can be made of the same or different material.

The locking device according to the invention can be widely used in many other applications, especially where long threaded rods are used for example in the field of ventilation, or where little space is available for tightening and fastening of nuts, such as for example manhole covers. It is also useful in different sorts of building and tubing, and in electrical cabinets and service hatches. Hence the invention is not to be considered limited to the above described embodiments, but may be varied within the scope of the enclosed claims.