Mooring line connector assembly and tensioner

Abstract

This disclosure relates to a locking mechanism for a connector assembly. The locking mechanism comprises a complementary male (2) and female (3). The female (3) comprises an inclined surface (36) and an engaging member (20) disposed thereon. The male and female parts each have grooved surfaces (9, 29) having asymmetrically shaped grooves. The male (2) extends through the female (3), and the grooved engaging member is located radially inward of the inclined surface (36), i.e., between the male and the outer sleeve (30). Load is transmitted from the male (2) to the grooved engaging member (20), and further from the grooved engaging member to the outer sleeve (30), but the load is transmitted to the outer sleeve only at the interface between the inclined surfaces of the grooved engaging member and the outer sleeve.

Description

Technical Field

[0001] The present invention relates to a locking mechanism, and more particularly to a mooring line connector assembly for connecting to a tension leg platform (TLP, including extended tension leg platforms (ETLPs)), a buoy for marine production, or a spar platform, etc., and a locking mechanism for a tensioner. The present invention is particularly intended for application in the renewal market, for example, when connecting a mooring line to an offshore wind turbine on the sea surface via a TLP, or when connecting a mooring line to a wave power generation device installed on the sea surface or in the sea.

Background Art

[0002] A tension leg platform (TLP) is a vertically moored floating structure (or buoy) typically used for oil and gas production in the ocean and floating offshore wind turbines. A TLP is particularly suitable for sea areas with a water depth of more than 300 meters and less than 1500 meters. By using a TLP for a floating offshore wind turbine, the sea areas where a wind power plant can be installed increase dramatically. Also, since a TLP is not permanently fixed, the turbine can be towed to a maintenance facility as needed, and installation and maintenance costs can be dramatically reduced.

[0003] A TLP is held in place by a plurality of tendons (usually steel, composite, rope, pipe, or chain, tendon), which are connected to an anchor point on the seabed in a generally vertical direction.

[0004] As mentioned above, underwater buoys and TLPs (whether supporting oil and gas production facilities or wind turbines) must be moored to the seabed, just like wave power generation equipment. These tendons are very long, and therefore, even slight differences in the elongation of each tendon (which seems unavoidable in the current situation) can result in differences in tendon length when tensile force is applied to multiple tendons.

[0005] Tensioning systems are used to maintain mooring structures in a stable and upright position, even when using tendons of different lengths. Typically, as described in US5,244,313A, these take the form of ratcheting tensioners and are usually supported on a flexible joint. The end of the tendon is provided with a tubular section having a helical thread, which engages with a female connector consisting of multiple segments with threaded faces radially inward. When the tubular section is retracted into the female connector, the multiple segments ratchet against the helical thread, and when the desired tension is reached, a cam ring rotates to engage and lock the segments into the helical thread. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] U.S. Patent No. 5,244,313 [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] However, such systems are complex and require numerous parts. Furthermore, the inventors found that the threaded surface could be subjected to large shear forces, potentially leading to failure, especially at the base of the thread where the load is most concentrated.

[0008] The present invention aims to provide an improved mooring line connector assembly. [Means for solving the problem]

[0009] According to a broader aspect of the present invention, a locking mechanism is provided comprising complementary male and female parts. The male and / or female parts may have a longitudinal axis. The locking mechanism may have a first end (optionally a load-side end) and a second end (optionally a tensile force-side end). The male part may include a rigid rod having a grooved outer surface. Each groove has a load-side flank and an opposing flank, which may have different angles. The load-side flank may be substantially perpendicular to the longitudinal axis of the locking mechanism. The female part may include an outer sleeve. The outer sleeve surrounds a plurality of grooved engaging members. The plurality of grooved engaging members comprises a grooved surface and opposing inclined surfaces. The outer sleeve has an inclined inner surface, which may have a shape in which the cross-section decreases toward the load-side end. The male part may penetrate the female part. The plurality of grooved engaging members are arranged radially inward of the inclined surfaces. The plurality of grooved engaging members are arranged between the male part and the outer sleeve. The load is transmitted from the male part to multiple grooved engaging members. The load is then transmitted from the multiple grooved engaging members to the outer sleeve. The load is transmitted from the multiple grooved engaging members to the outer sleeve only at the interface between the inclined surfaces of the multiple grooved engaging members and the inclined surfaces of the outer sleeve.

[0010] Accordingly, according to a first aspect of the present invention, a locking mechanism is provided comprising complementary male and female parts having a longitudinal axis. The locking mechanism has a first end on the load side and a second end on the tensile side. The male part includes a rigid rod having a grooved outer surface, each groove having a load-side flank and an opposing flank, the two flanks having different angles, the load-side flank being substantially perpendicular to the longitudinal axis of the locking mechanism. The female part includes an outer sleeve, which surrounds a plurality of grooved engaging members. The plurality of grooved engaging members have a grooved surface and opposing inclined surfaces, and the outer sleeve has an inclined inner surface whose cross-section decreases toward the load-side end. The male part penetrates the female part, and the plurality of grooved engaging members are positioned between the male part and the outer sleeve, radially inward of the inclined surfaces. The load is transmitted from the male part to the plurality of grooved engaging members, and from the plurality of grooved engaging members to the outer sleeve, and the load is transmitted only at the interface between the inclined surfaces of the plurality of grooved engaging members and the inclined surfaces of the outer sleeve.

[0011] Advantageously, the combination of the angles of the multiple grooved engaging members and the difference in angles on the opposing inclined surfaces creates a locking mechanism that is essentially self-engaging and distributes the load more uniformly along the length of the interface between the male and female parts.

[0012] The locking mechanism may have at least two grooved engaging members. The locking mechanism may have at least three grooved engaging members. The locking mechanism may have at least four grooved engaging members. The locking mechanism may have at least five engaging members. The locking mechanism may have at least six grooved engaging members. The locking mechanism may have six grooved engaging members. The locking mechanism may have at least seven engaging members. The locking mechanism may also have at least eight grooved engaging members. Multiple grooved engaging members may be arranged in a line. That is, multiple grooved engaging members may all be arranged in the same axial position.

[0013] Multiple grooved engaging members may be movable along an inclined surface. Multiple grooved engaging members may move between an engaged position and a disengaged position. The engaged position corresponds to the position where the multiple grooved engaging members engage with the grooved outer surface of the male part. The disengaged position corresponds to the position where the male part is movable along the longitudinal axis of the locking mechanism. In the disengaged position, the multiple grooved engaging members may be positioned radially outward and axially away from the load-side end relative to the engaged position. Multiple grooved engaging members may be biased toward the engaged position. Each grooved engaging member may be biased by a biasing member. The biasing member may be a spring such as a wire compression spring, or gas struts, etc.

[0014] The load-side flanks of the multiple grooves in the male part may have angles greater than 70°, preferably greater than 75°, more preferably greater than 80°, for example greater than 85°, or between 85° and 90° with respect to the longitudinal axis of the locking mechanism.

[0015] Advantageously, the closer the angle of the load-side flank of the male groove is to perpendicular to the longitudinal axis, the more directly the applied load is transmitted through the flank.

[0016] The multiple opposing flanks of the multiple grooves in the male part may have angles of 10° to 60°, preferably 20° to 50°, more preferably 30° to 50°, for example 40° to 50°, with respect to the longitudinal axis of the locking mechanism.

[0017] Advantageously, by applying the aforementioned angle to the opposing flank, the load acting on the load-side flank can be easily transmitted from the body of the male connector.

[0018] Each groove on the grooved surface of the female part may also have a load-side flank and an opposing flank. The load-side flank of the groove in the female part may have an angle greater than 70°, preferably greater than 75°, more preferably greater than 80°, for example greater than 85°, or between 85° and 90° with respect to the longitudinal axis of the locking mechanism.

[0019] Advantageously, as the angle of the load side flank of the groove of the female part approaches perpendicular to the longitudinal axis, the acting load is transmitted more directly through the flank.

[0020] The opposing flanks of the groove of the female part may have an angle of 10° to 60°, preferably 20° to 50°, more preferably 30° to 50°, for example 40° to 50° with respect to the longitudinal axis of the locking mechanism.

[0021] Advantageously, by providing the opposing flanks with the above-mentioned angles, there is an advantage that the load acting on the load side flank can be easily transmitted to the main body of the female connector.

[0022] The plurality of grooves of the male part and the engaging member may have the same profile. The plurality of load side flanks of the male part and the female part may have the same angle. The opposing flanks of the male part and the female part may have the same angle. In use, the load side flank of the male part may face the load side flank of the female part.

[0023] Advantageously, since the grooves of the male part and the female part have the same profile, the male part and the female part contact each other over the entire surface and disperse the load.

[0024] The grooved surfaces of the plurality of engaging members may be curved. The grooved surface of the engaging member may be curved concave. The grooved surface of the male part may be curved. The grooved surface of the male part may be curved convex. The radii of curvature of the grooved surfaces of the plurality of engaging members and the grooved surface of the male part may be the same.

[0025] The inclined surface of the grooved engaging member may have an angle of 5° to 60°, preferably 10° to 40°, more preferably 20° to 30°, for example 20° to 25° from the longitudinal axis. The inclined surface may have a single pitch.

[0026] The inclined surface of the outer sleeve may also have an angle of 5° to 60°, preferably 10° to 40°, more preferably 20° to 30°, for example 20° to 25° from the longitudinal axis. The inclined surface may have a single pitch.

[0027] The inclined surface of the engaging member and the inclined surface of the outer sleeve may have the same angle.

[0028] Advantageously, by angling the inclination as described above, the plurality of engaging members are essentially drawn into the engagement position along the taper, and since the load acts radially, the locking effect is enhanced.

[0029] The tapered bore may have a circular cross-section. The inclined surface of the outer sleeve may have a circular cross-section. That is, the inner surface of the outer sleeve may form a frustum-shaped bore. The tapered bore may be frustum-shaped.

[0030] The tapered bore may have a polygonal cross-section. The inclined surface of the outer sleeve may have a polygonal cross-section. That is, the inner surface of the outer sleeve may form a frustum-shaped bore. The tapered bore may be frustum-shaped. The inclined surface of the outer sleeve may have at least three surfaces. The inclined surface of the outer sleeve may have at least four surfaces. The inclined surface of the outer sleeve may have at least six surfaces. The inclined surface of the outer sleeve may have at least eight surfaces. These surfaces may have the same profile.

[0031] By providing a tapered inner bore with a polygonal cross-section, there is an advantage that the inclined surface of the taper (and the inclined surface of the engaging member) can be made flat. The flat inclined surface can more evenly disperse the load between the two surfaces and avoid local stress concentration.

[0032] The locking mechanism may include grooved engaging members having the same number of surfaces as the inclined surface of the outer sleeve. The plurality of grooved engaging members may be entirely placed on the inclined surface of the outer sleeve.

[0033] The inclined surface of the grooved engaging member and the corresponding inclined surface of the outer sleeve may have the same pitch. The inclined surface of the outer sleeve may be longer than the inclined surfaces of the plurality of grooved engaging members.

[0034] Multiple grooved engaging members may have at least three grooves, preferably at least five grooves, more preferably at least ten grooves, for example, at least fifteen grooves.

[0035] The male part may include a rigid bar, preferably a hollow bar, but may also be substantially solid. A solid bar can have a higher ratio of tensile strength to width compared to a hollow bar, while a hollow bar can have a larger outer circumference for the same weight, thereby increasing its resistance to bending. The male part may have a length of at least 1m, 3m, 5m, or 7m. The male part may be linear. The male part may have a circular cross-sectional shape.

[0036] The shape defined by the multiple inner edges of the multiple engaging members may be smaller in the engaged position than in the disengaged position. For example, in a female connector having a circular bore and with multiple locking members arranged circumferentially around it, the multiple locking members may protrude radially inward in the engaged position than in the disengaged position, so that the distance between opposing multiple engaging members in the engaged position is smaller than the distance between opposing multiple engaging members in the disengaged position. In the engaged position, the multiple grooves of the multiple engaging members may be in contact with the multiple grooves of the male part. In the disengaged position, the multiple grooves of the multiple engaging members may be disengaged from the multiple grooves of the male part.

[0037] The female portion may have a first open end that defines the entrance to the bore into which the male portion is inserted, and a second end opposite to it. The multiple engaging members may be movable between an engaged position near the first open end and an unengaged position near the second end. The multiple engaging members may be biased toward the first open end. The second end is preferably open, which allows the male portion to be withdrawn from the first open end to the second end.

[0038] This movement pulls the male end towards the first open end (i.e., the outside of the entrance), and when attempting to move the locking member, the locking member is pulled into engagement. Conversely, when the male end is inserted, it pushes the engaging member toward the second end, moving the engaging member to the disengaged position (against biasing forces in some cases). Therefore, insertion is easy, and the male end will not be pulled out when tensile force is acting.

[0039] The second end of the female part may have a shape for connecting to a tensioner or release mechanism. The female part is shaped to be connectable to a tensioner. By shaping the female part to receive a tensioner, the tensioner can pull the male part linearly through the female part even when the angle between the female part and the structure changes. The second end formed in this shape may be planar.

[0040] The engaging member may include a coupler. Each engaging member may include a coupler. The coupler may be located at the second end of the female part, or may be located extending from the second end of the female part. By extending from the second end of the female part, the coupler can be configured to engage with a tensioner or release mechanism.

[0041] The female or preferably male part may be connectable to a tether. For this purpose, the male or female part may have a terminal portion for connecting to a tether. The terminal portion may have an opening for receiving a clivis pin at the end of the tether, or a clivis for attaching to the opening at the end of the tether.

[0042] In particular, the male connector may have a tether connection terminal at one end and a guide wire connection terminal at the opposite end.

[0043] The locking mechanism may be provided within the connector. The locking mechanism may be provided within the adjustable connector. The connector may be a submersible connector. The submersible connector may be a connector for connecting a submersible cable to a wind turbine.

[0044] The underwater connector may also be a connector for connecting the tension leg platform to the seabed. [Brief explanation of the drawing]

[0045] Hereinafter, in order to provide a clearer understanding of the present invention, one embodiment will be described with reference to the accompanying drawings and with illustrative examples. [Figure 1] This is a perspective view of a connector assembly equipped with a locking mechanism according to a first embodiment of the present invention. [Figure 2] Figure 1 is an exploded view of the connector assembly. [Figure 3] Figure 1 is a cross-sectional view of the unengaged interface between the male and female connectors in the connector assembly. [Figure 4] Figure 1 is a cross-sectional view of the locking mechanism in the connector assembly in its disengaged state. [Figure 5] This is a cross-sectional view of the engaged state of the locking mechanism in the connector assembly shown in Figure 1. [Figure 6] This is a perspective view of a connector assembly equipped with a locking mechanism according to a second embodiment of the present invention. [Figure 7] Figure 6 is an exploded view of the connector assembly. [Figure 8] Figure 6 is a cross-sectional view of the unengaged interface between the male and female connectors in the connector assembly. [Figure 9] Figure 6 is a cross-sectional view of the locking mechanism in the connector assembly in its disengaged state. [Figure 10] Figure 6 is a cross-sectional view of the engaged state of the locking mechanism in the connector assembly. [Modes for carrying out the invention]

[0046] In the following explanation, terms such as "upper side" and "lower side" are used based on the orientation of the connector assembly shown in the diagram. This is for convenience to facilitate understanding, and the actual usage orientation is not limited to this. Therefore, depending on the usage situation, the part labeled "upper side" may become the "lower side."

[0047] Referring to Figures 1 to 5, a mooring line connector assembly 1 equipped with a locking mechanism according to a first embodiment of the present invention is shown. The connector assembly 1 comprises a male connector 2 and a female connector 3. To facilitate the description of the mooring line connector assembly, the male connector 2 is understood to define a longitudinal axis AA extending along its length.

[0048] Unless otherwise specified, all major components of connector assembly 1 are formed from suitable metal materials that can be easily selected by a person skilled in the art who is proficient in the manufacture of submersible connectors, and are manufactured by machining.

[0049] The male connector 2 and the female connector 3 are configured complementaryly, with the female connector 3 (most clearly shown in Figures 2 to 5) having a cylindrical bore 7 that passes through the male connector 2, the bore having an inner diameter slightly larger than the outer diameter of the straight rigid bar 8 having a circular cross-section, which is the main component of the male connector 2.

[0050] As is most clearly shown in Figures 3 to 5, the rigid bar 8 of the male connector 2 has numerous circumferential grooves 9 formed therein. The numerous grooves 9 are provided along most of the length of the rigid bar 8, defining multiple positions where the female connector 3 can be connected to the male connector 2, thereby allowing the tensile force applied to the mooring line to be varied.

[0051] One end of the male connector 2 is provided with a proximal terminal portion 10 located directly above the first groove, which has a hole (eye) for receiving a guide wire 11 (guide wire terminal portion shown in the figure) used to pass the male connector 2 into the female connector 3.

[0052] The distal end of the male connector 2 is provided with a distal end portion 12 for connecting a tether 13 (or tendon) via a tether end portion 15, and this distal end portion 12 is the load end of the male connector. The distal end portion 12 is provided with a joint 14 that can rotate around a horizontal axis perpendicular to the longitudinal axis of the male connector 2. The joint 14 also has a bore formed through it that is perpendicular to its rotation axis (and also perpendicular to the longitudinal axis AA of the male connector 2). This bore allows the tether end portion 15 to be connected to the joint 14 using a shackle formed inside the tether end portion 15 and a corresponding bolt 16. The axis on which the joint 14 rotates and the axis on which the tether end portion 15 rotates around the bolt 16 are combined, allowing the tether to extend linearly from the end portion 15, thus avoiding stress due to bending.

[0053] As mentioned above, each groove 9 of the male connector 2 represents a different point along the length of the male connector 2 to which the female connector 3 may be connected (this allows the relative position of the male connector 2 and the female connector 3 to be changed, thereby adjusting the tension acting on the tether 13).

[0054] The female connector 3 includes four engaging members 20 arranged circumferentially around a cylindrical bore 7 within the female connector 3 for engaging with any groove of the male connector 2. The four engaging members 20 as a whole form a frustoconical shape, and the cylindrical bore 7 penetrates between its upper and lower surfaces.

[0055] Since each engaging member 20 has the same shape, one engaging member 20 will be described in detail below. The engaging member 20 has a quarter-circular annular cross-section and comprises a radial inner wall 21, a radial outer wall 22, an upper surface 23, and a lower surface 24. The lower surface 24 is configured to face the tendon side when in use (details will be described later).

[0056] The radial inner wall 21 is perpendicular to the lower surface 24 and has a concave curved surface with the same radius of curvature as the male connector. Multiple grooves 29 extending in the lateral direction are formed in the radial inner wall 21, and in this embodiment there are 19 grooves.

[0057] The radial outer wall 22 is curved in a convex shape and is tapered such that the radius of curvature increases from the lower surface 24 to the upper surface 23. In this embodiment, the taper angle A is 20° with respect to the radial inner wall 21 (parallel to the longitudinal axis AA), but in other embodiments described later, the angle may be in the range of 5° to 60°. Because the radial inner wall 21 is perpendicular to the lower surface 24 and a taper is formed on the radial outer wall 22, the thickness between the two walls decreases from the upper surface 23 to the lower surface 24, and the engaging member 20 becomes thinner near the lower surface 24.

[0058] The upper surface 23 is angled perpendicular to the radial outer wall 22. In this embodiment, the connector is configured to be used in conjunction with an arbitrary release mechanism (not shown), and the female connector 3 is equipped with a coupler for connection to the release mechanism (details will be described later). A coupler connection point 25 is provided in the center of the upper surface 23, and in this embodiment, the coupler connection point 25 is formed by a screw hole extending in a direction perpendicular to the upper surface 23.

[0059] As is most clearly shown in Figure 3, the multiple grooves 9 of the male connector 2 and the multiple grooves 29 of the engaging member 20 are asymmetrical and have the same but inverted "V" shaped profile. Each groove 9, 29 has a load-side flank 9A, 29A and an opposing flank 9B, 29B. In the male connector 2, the load-side flank 9A faces the load-side end 13 of the male connector 2, and in the engaging member 20, the load-side flank 29A faces the upper surface 23 of the engaging member 20.

[0060] In this embodiment, the load-side flanks 9A and 29A are approximately perpendicular to the longitudinal axis AA of the connector (and the tensile force acting along it), and their angle C is 85° with respect to the longitudinal axis AA. In this embodiment, the opposing flanks 9B and 29B are inclined at an angle D of 45° with respect to the longitudinal axis AA.

[0061] To prevent severe damage to the tapered point between the two grooves 9,29, points 9C,29C are either angular or rounded instead.

[0062] Although these are described as grooves 9 and 29, a person skilled in the art would understand that the load-side flanks 9A and 29A and the opposing flanks 9B and 29B of adjacent grooves 9 and 29 can also be considered as projections or ridges 9' and 29'.

[0063] As described above, the engaging member 20 constitutes part of the female connector 3. The female connector 3 is composed of an outer casing 30 that is roughly rectangular in shape, having an upper surface 31, a lower surface 32 (facing the tendon side when in use), and four side surfaces 33. An upper opening 34 is formed on the upper surface 31, and a lower opening 35 is formed on the lower surface 32. Between these two openings, a tapered bore 36 is formed that extends along the longitudinal axis AA. The taper is formed such that the diameter of the bore 36 decreases from the upper opening 34 to the lower opening 35. The taper angle (B) is the same as the taper of the engaging member, and in this embodiment it is 20° with respect to the longitudinal axis AA.

[0064] A pair of marine bearings 33A for pivotally mounting the female connector 3 are provided on the two opposing sides 33.

[0065] The engaging member 20 is positioned around the tapered bore 36, with its radially outer wall 22 in contact with the tapered bore 36, and its lower surface 24 close to the lower surface 32 of the casing 30. To hold the engaging member 20 inside the casing 30, the upper opening 34 and lower opening 35 are partially sealed by an upper retaining plate 37 and a lower retaining plate 38, respectively. The retaining plates 37 and 38 are annular plates with an outer diameter larger than the respective openings 34 and 35, and have concentric openings 37A and 38A in their centers through which the male connector 2 can pass (details will be described later). In this example, the retaining plates 37 and 38 are fixed to the casing 30 by a number of bolts. In addition to holding the engaging member 20, in some embodiments, environmental seals (such as rubber O-rings or gaskets) may be provided in the concentric openings 37A and 38A of the retaining plates 37 and 38 to reduce or prevent foreign matter from entering the inside of the connector.

[0066] When a release mechanism is provided, the upper retaining plate 37 has four coupler holes 39 that are arranged at equal intervals in the circumferential direction of the plate and aligned with the coupler connection points 25 of the engaging member 20. A coupler 40 passes through each coupler hole 39 and engages with the corresponding coupler connection point 25. Each coupler 40 has a rod 41 with a circular cross-section, and a threaded portion 43 is formed at the distal end of the rod 41. A head 45 is provided at the proximal end on the opposite side, and the head 45 has a stepped portion that protrudes radially, and the release mechanism can be attached to this stepped portion.

[0067] The operation of the connector, particularly the locking mechanism, will be explained with reference to Figures 4 and 5.

[0068] When in use, the female connector 3 is pivotably mounted to the tension leg platform (TLP) via a marine bearing 33A. Alternatively, the female connector 3 may optionally be pivotably mounted within a cradle, which in turn may be pivotably mounted to the TLP via a hang-off porch. In this case, the pivot axis of the female connector 3 in the cradle is perpendicular to the pivot axis of the cradle on the TLP.

[0069] The TLP is equipped with the required number of female connectors 3, which are attached via hang-off pouches, supported by a cradle, and held pivotably within the cradle. This configuration allows the female connectors 3 to pivot within the cradle within a range of up to ±10° relative to the normal direction, and furthermore, the cradle itself can pivot within a range of up to ±10° relative to the normal direction in a direction perpendicular to the pivot axis of the female connectors 3.

[0070] A corresponding number of male connectors 2 are provided, each connected to the tether 13 via a terminal 12. The opposite end of the tether 13 is made of, for example, a composite fiber rope and is secured to the seabed in a conventional manner.

[0071] A guide wire (not shown) is attached to the eye 10 of the male connector 2 and inserted through the bore 7 of the female connector 3 from the bottom to the top. This guide wire is pulled up through the female connector 3 to the corresponding male connector 2.

[0072] As the male connector 2 is pulled into the female connector 3 using the tensioner, the opposing flank 9B of the groove 9 of the male connector 2 contacts the opposing flank 29B of the groove 29 of the engaging member 20. This contact causes the engaging member 20 to slide upward and radially outward along the tapered bore 36. As the engaging member 20 continues to move radially outward, the amount of contact between the two opposing flanks 9B, 29B decreases until the two flanks 9B, 29B no longer contact each other (i.e., the engaging member is in the disengaged position). At that point, the engaging member 20 moves downward along the tapered bore 36, returning towards the bottom opening 35 (i.e., towards the engaged position). In doing so, the engaging member 20 also moves radially inward, engaging with the opposing flank 29B and then the opposing flank 9B of the next groove 9. This process is repeated, ratcheting the male connector 2 into the female connector 3, until the tether 13 is tensioned as desired.

[0073] Due to the inclination of the tapered bore 36, the engaging member 20 is essentially subjected to a force toward the engaged position, although this movement may be assisted by a biasing means. The biasing means may consist of one or more springs 50, as in this embodiment, or a gas strut or other mechanism may be used.

[0074] After the desired tensile force is applied to the tether 13, the tensioner is removed, and the tensile force acting on the tether 13 pulls the male connector 2 downward, causing the load-side flanks 9A and 29A to come into contact with each other. In this state, the tensile force of the tether 13 is transmitted to the female connector 3 via the engaging member 20. As the tensile force is transmitted through the engaging member 20, the engaging member 20 is further pulled toward the lower opening 35. As the engaging member 20 approaches the lower opening 35, the inclination of the tapered bore 36 pushes the engaging member 20 radially inward. The inclination angle B directs the larger component of the force acting between the male connector 2 and the engaging member 20 radially, thereby reducing the load acting on the individual ridges 9' and 29' in a less "lateral" direction, and thus reducing the risk of severe failure of the ridges 9' and 29'.

[0075] This large radial component ensures that the load is evenly distributed across all ridges 9',29'. The inventors observed that in conventional connectors, the load is primarily concentrated on the first few ridges near the load end, and adding further ridges has only limited effect. However, in the present invention, as described above, the engaging member 20 is pushed significantly radially inward, so the remaining lateral force is evenly distributed across all ridges 9',29', further reducing the risk of severe damage to the ridges near the distal end.

[0076] Furthermore, the female connector 3 provides an improved engagement with the male connector 2, reducing the risk of damage to the grooves 9,29 and ridges 9',29', and the asymmetrical shape of the grooves 9,29 themselves also improves the durability of the grooves or ridges. Because the load-side flanks 9A,29A are substantially perpendicular to the applied force and the opposing flanks are inclined toward the ridge base, the transmission of force from the body of the male connector 2 to the load-side flank 9A and from the load-side flank 29A to the entire engaging member is improved.

[0077] Since the load-side flanks 9A and 29A are substantially perpendicular to the applied force (a 5° deviation from perpendicular in this embodiment), the force is transmitted to the engaging member almost in the same line as the force acting on the tether. As a result, the engaging member 20 is pushed forward mainly along its longitudinal axis. That is, of the force acting from the male connector 2 to the engaging member 20, the component that pushes the engaging member 20 radially outward is very small.

[0078] To ensure that the engaging member 20 makes maximum contact with the male connector 2, the tapered bore 36 is formed as a single-pitch inclined surface and is dimensioned so that the engaging member 20 rests completely on the inclined surface up to its lowest position (i.e., the position where the side edges contact each other).

[0079] In some embodiments, it may be desirable to have a means to release the connector for maintenance work on the TLP, etc. In such cases, the connector 1 may be provided with a plurality of couplers 40. As described above, each coupler 40 is provided with a rod 41 having a circular cross-section, and the distal end portion 42 of the rod 41 is formed with a threaded portion 43 that is screwed into the corresponding engaging member 20. The proximal end portion on the opposite side is provided with a head 45, and the head 45 is formed with a radially protruding step, and a release mechanism can be attached to this step.

[0080] When releasing the connector, the release mechanism engages with the head 45 of the coupler 40 and pulls it up. This causes the engaging member 20 to move upward through the tapered bore 36 to the disengaged position, making it possible to remove the male connector 2 from the female connector 3.

[0081] Referring to Figures 6 to 10, another mooring line connector assembly 101 with a locking mechanism according to a second embodiment of the present invention is shown. The connector assembly 101 of this embodiment is similar to the connector assembly 1 described above, and the corresponding components are denoted by reference numerals in the 100s. The connector assembly 101 comprises a male connector 102 and a female connector 103. To facilitate the description of the mooring line connector assembly, the male connector 102 is understood to define a longitudinal axis AA extending along its length.

[0082] Unless otherwise specified, the main components of the connector assembly 101 are formed from suitable metal materials that can be easily selected by a person skilled in the art who is proficient in the manufacture of submersible connectors, and are manufactured by machining.

[0083] The male connector 102 and the female connector 103 are configured complementaryly, with the female connector 103 (most clearly shown in Figures 6 to 8) having a cylindrical bore 107 that passes through the male connector 102, which has an inner diameter slightly larger than the outer diameter of the straight rigid bar 108 (having a circular cross-section), a main component of the male connector 102.

[0084] As is most clearly shown in Figures 6 to 10, the rigid bar of the male connector 102 has multiple circumferential grooves 109 formed therein.

[0085] The groove 109 extends over most of the length of the bar 108 and defines multiple positions where the female connector 103 can be connected to the male connector 102, thereby allowing adjustment of the tensile force applied to the mooring line.

[0086] One end of the male connector 102 is provided with a proximal terminal portion 110 directly above the first groove, and an eye is formed to receive the guide wire 111 (guide wire terminal portion shown in the figure). The guide wire 111 is used to pass the male connector 102 into the female connector 103.

[0087] The distal end of the male connector 102 is provided with a distal end portion 112 for connecting a tether 113 (or tendon) via a tether end portion 115, and this distal end portion of the male connector becomes the load end 112. The distal end portion 112 is provided with a joint 114 that can pivot around a transverse axis perpendicular to the longitudinal axis of the male connector 102. The joint 114 also has a bore formed through it that is perpendicular to its pivot axis (and also perpendicular to the longitudinal axis AA of the male connector 102). This bore connects the tether end portion 115 to the joint 114 by a shackle formed on the bolt 116 corresponding to the tether end portion 115. The arrangement of the pivot axis of the joint 114 and the axis of the bolt 116 on which the tether end portion 115 pivots allows the tether to extend linearly from the tether end portion 115, thus avoiding bending stress.

[0088] As described above, each groove 109 of the male connector 102 defines different positions along the length of the male connector 102 into which the female connector 103 will be coupled in order to change the relative position of the male connector 102 and the female connector 103 and to change the tensile force acting on the tether 113.

[0089] To engage with any groove, the female connector 103 includes six engaging members 120 arranged circumferentially around a cylindrical bore 107 within the female connector 103. The six engaging members 120 as a whole have a frustoconical shape with a cylindrical bore penetrating between their upper and lower surfaces.

[0090] Since each engaging member has the same shape, only one engaging member will be described below. Each engaging member 120 has an isosceles trapezoidal cross-section and is equipped with an inner wall 121, an outer wall 122, an upper surface 123, and a lower surface 124, with the lower surface 124 facing the tendon side when in use (more detailed information will be provided later).

[0091] The inner wall 121 is perpendicular to the lower surface 124 and forms a concave curved surface having the same radius of curvature as the male connector 102. Multiple grooves 129 extending in the lateral direction are formed in the inner wall 121, and in this embodiment, 19 grooves are provided.

[0092] The outer wall 122 is inclined, and the distance between the inner wall 121 and the outer wall 122 increases from the bottom surface 124 to the top surface 123. In this embodiment, when the inclination with respect to the radial inner wall 121 is measured, the angle A is 20°, but in other embodiments described later, it may be in the range of 5° to 60°. Because the radial inner wall 121 is perpendicular to the bottom surface 124 and the radial outer wall 122 is inclined, when the thickness of the engaging member is measured between the two walls, the thickness between the two walls decreases between the top surface 123 and the bottom surface 124, and the engaging member 120 becomes thinner near the bottom surface 124.

[0093] The upper surface 123 is angled perpendicular to the radial outer wall 122. In this embodiment, the connector is configured to be used in conjunction with an arbitrary release mechanism (not shown), and the female connector 103 is equipped with multiple couplers 140 for connection to the release mechanism, details of which will be described later. A coupler connection point 125 is provided in the center of the upper surface 123, and in this embodiment, the coupler connection point 125 is formed by a screw hole extending in a direction perpendicular to the upper surface 123.

[0094] As is most clearly shown in Figure 8, the groove 109 of the male connector 102 and the groove 129 of the engaging member 120 are asymmetrical and have the same but inverted "V" shaped profile. Each groove 109, 129 has a load-side flank 109A, 129A and an opposing flank 109B, 129B. In the male connector 102, the load-side flank 109A faces the load end 113 of the connector 102, and in the engaging member 120, the load-side flank 129A faces the upper surface 123 of the engaging member 120.

[0095] In this embodiment, the load-side flanks 109A and 129A are approximately perpendicular to the longitudinal axis AA of the connector (and the tensile force acting along it), with an angle of 85° to 90°. In this embodiment, the opposing flanks 109B and 129B are inclined at an angle of 45° with respect to the longitudinal axis AA.

[0096] To prevent severe damage to the tapered points 109C,129C formed between the two grooves 109,129, the points 109C,129C are either angular or, conversely, rounded.

[0097] Although described as grooves 109 and 129, a person skilled in the art may understand the portion formed by the load-side flanks 109A and 129A and the opposing flanks 109B and 129B of the adjacent groove as projections or ridges 109' and 129'.

[0098] As described above, the engaging member 120 constitutes part of the female connector 103. The female connector 103 is made up of an outer casing 130 which is generally rectangular in shape and has an upper surface 131, a lower surface 132 (facing the tendon side when in use), and four sides 133. An upper opening 134 is formed on the upper surface 131 and a lower opening 135 is formed on the lower surface 132, and a tapered bore 136 extends between the two openings along the longitudinal axis AA, and this tapered bore 136 has a hexagonal cross-section. The taper in this case is formed so that the cross-sectional area of ​​the tapered bore 136 decreases in the area between the upper opening 134 and the lower opening 135. The taper angle (B) is the same as the taper of the engaging member 120, and in this embodiment it is 20° when measured with respect to the longitudinal axis AA.

[0099] On two opposing sides of the side surface 133, marine bearings 133A are provided to pivotally support the female connector 103.

[0100] The engaging member 120 is positioned around the tapered bore 136, with its outer wall 122 in contact with the tapered bore 136, and its lower surface 124 positioned close to the lower surface 132 of the casing 130. To hold the engaging member 120 within the casing 130, the upper opening 134 and lower opening 135 are partially sealed by an upper retaining plate 137 and a lower retaining plate 138, respectively. The retaining plates 137 and 138 are annular plates with an outer diameter larger than the respective openings 134 and 135, and have concentric openings 137A and 138A in their centers through which the male connector 102 can pass (details will be described later). In this example, the retaining plates 137 and 138 are fixed to the casing 130 by a number of bolts.

[0101] In addition to the function of holding the engaging member 120, in some embodiments, the concentric openings 137A and 138A in the upper retaining plate 137 and lower retaining plate 138 may be provided with environmental seals (such as rubber O-rings or gaskets) to reduce or prevent foreign matter from entering the inside of the connector.

[0102] When a release mechanism is provided, the upper retaining plate 137 is provided with six coupler holes 139 that are equally spaced in the circumferential direction of the plate and aligned with the coupler connection points 125 of the engaging member 120. A coupler 140 penetrates each coupler hole 139 and engages with the corresponding coupler connection point 125. Each coupler 140 comprises a rod 141 having a circular cross-section, and a threaded portion 142 is provided at the distal end of the rod 141. A head 145 is provided at the proximal end on the opposite side, and the head 145 forms a stepped portion that protrudes radially, and the release mechanism can be attached to this stepped portion.

[0103] The operation of connector 101, particularly the operation of the locking mechanism, will be described with reference to Figures 9 and 10.

[0104] When in use, the female connector 103 is pivotably mounted to the tension leg platform (TLP) via the marine bearing 133A. Alternatively, the female connector 103 may be pivotably mounted within a cradle, which may be pivotably mounted to the TLP via a hang-off pouch, in which case the pivot axis of the female connector 103 within the cradle is perpendicular to the pivot axis of the cradle on the TLP.

[0105] The TLP is equipped with the required number of female connectors 103, which are attached via hang-off pouches, supported by a cradle, and held pivotably within the cradle. This configuration allows the female connectors 103 to pivot up to 10° on both sides of the normal within the cradle, and the attachment of the cradle to the hang-off pouches allows the female connectors 103 within the cradle to pivot at an angle of up to 10° on both sides of the normal in a direction perpendicular to the axis of pivot.

[0106] A corresponding number of male connectors 102 are provided, each connected to the tether 113 via a distal end 112. The opposite end of the tether 113 is made of, for example, a composite fiber rope and is secured to the seabed in a conventional manner.

[0107] A guide wire (not shown) is attached to the eye 111 of the male connector 102 and inserted through the bore 107 of the female connector 103 from bottom to top. This guide wire is pulled up through the female connector 103 to the corresponding male connector 102.

[0108] As the male connector 102 is pulled into the female connector 103 using the tensioner, the opposing flank 109B of the groove 109 of the male connector 102 comes into contact with the opposing flank 129B of the groove 129 of the engaging member 120. This contact causes the engaging member 120 to slide upward and radially outward along the tapered bore 136. As the multiple engaging members 120 continue to move radially outward, the amount of contact between the opposing flanks 109B and 129B decreases until the two flanks 109B and 129B no longer come into contact (i.e., the engaging member is in the disengaged position). At that point, the engaging member 120 moves downward along the tapered bore 136 and returns towards the lower opening 135 (i.e., towards the engaged position). As the multiple engaging members 120 move radially inward, engage with the opposing flank 129B, and then engage with the opposing flank 109B of the next groove 109. This process is repeated while ratcheting the male connector 102 onto the female connector 103 until the desired tension is applied to the tether 113.

[0109] Due to the inclination of the frustopyramidal bore 136, the engaging member 120 is essentially subjected to a force toward the engaged position, although this movement may be assisted by a biasing means. The biasing means may consist of one or more springs 150, as in this embodiment, or a gas strut or other similar mechanism may be used.

[0110] Compared to the previous embodiment, there are advantages to using a truncated pyramidal bore 136 instead of a truncated conical bore. Specifically, since both the bore 136 and the outer wall 122 of the engaging member 120 are composed of planes, the engaging member 120 can contact the bore 136 with the entire outer wall 122. In contrast, in the first embodiment, the bore 36 and the outer wall 22 are curved surfaces with varying radii of curvature, and when the engaging member 20 moves along the bore 36, there may be parts where the radii of curvature of the outer wall 22 and the bore 36 do not match, which may result in localized load concentration. By using an interface between planes, the load is uniformly distributed across the entire outer wall 122.

[0111] After the desired tensile force is applied to the tether 113, the tensioner is removed, and the tensile force acting on the tether 113 pulls the male connector 102 downward, causing the load-side flanks 109A and 129A to come into contact with each other. In this state, the tensile force of the tether 113 is transmitted to the female connector 103 via the multiple engaging members 120. As the tensile force is transmitted through the multiple engaging members 120, the multiple engaging members 120 are further pulled toward the lower opening 135. As the multiple engaging members 120 approach the lower opening 135, the inclination of the truncated pyramidal bore 136 pushes the multiple engaging members 120 radially inward. The inclination angle B directs the larger component of the force acting between the male connector 102 and the multiple engaging members 120 radially, thereby reducing the load acting on the individual ridges 109' and 129' in a less "lateral" direction, and reducing the risk of severe failure of the ridges 109' and 129'.

[0112] This large radial component ensures that the load is evenly distributed across all ridges 109', 129'. The inventors found that in conventional connectors, the load is primarily concentrated on the first few ridges near the load end, and adding further ridges has only limited effect. However, in the present invention, as described above, the multiple engaging members 120 are pushed significantly radially inward, so the remaining lateral force is evenly distributed across all ridges 109', 129', further reducing the risk of severe damage to the ridges near the distal end.

[0113] Furthermore, the female connector 103 provides improved engagement with the male connector 102, reducing the risk of damage to the grooves 109, 129 and ridges 109', 129', and the asymmetrical shape of the grooves 109, 129 themselves also improves the durability of the grooves or ridges. Because the load-side flanks 109A, 129A are substantially perpendicular to the applied force and the opposing flanks are inclined toward the ridge base, the transmission of force from the body of the male connector 102 to the load-side flank 109A and from the load-side flank 129A to the entire engaging member is improved.

[0114] Similarly, because the flanks 109A and 129A are substantially perpendicular to the applied force (a 5° deviation from perpendicular in this embodiment), the force is transmitted to the engaging member almost in the same line as the force acting on the tether. As a result, the engaging member 120 is pushed down mainly along its longitudinal axis. That is, of the force acting from the male connector 102 on the engaging member 120, the component that pushes the engaging member 120 radially outward is very small.

[0115] To ensure that the engaging member 120 makes maximum contact with the male connector 102, the tapered bore 136 is formed as a single-pitch inclined surface and is sized so that the engaging member 120 rests completely on the inclined surface up to its lowest position (i.e., the position where the side edges contact each other).

[0116] In some embodiments, it may be desirable to have a means to release the connector for maintenance work on the TLP, etc. In such cases, the connector 101 may be provided with a plurality of couplers 140. As described above, each coupler 140 is provided with a rod 141 having a circular cross-section, and a threaded portion 142 is formed at the distal end of the rod 141 which is screwed into a corresponding engaging member 120. A head 145 is provided at the proximal end on the opposite side, and the head 145 has a stepped portion that protrudes radially, and a release mechanism can be attached to this stepped portion.

[0117] When the connector is released, the release mechanism engages with the head 145 of the coupler 140 and pulls it up. This causes the engaging member 120 to move its tapered bore 136 upward to the disengaged position, making it possible to detach the male connector 102 from the female connector 103.

[0118] The embodiments described above are for illustrative purposes only. Many modifications are possible without departing from the scope of the present invention (as defined by the appended claims). For example, although the locking mechanism of the present invention has been described in application to an adjustable connector for TLP, it may also be applicable to other applications, including non-adjustable connectors. [Industrial applicability]

[0119] According to the present invention, a locking mechanism is provided comprising complementary male and female parts having longitudinal axes, and through a combination of the angles of the multiple grooved engaging members and the angle difference with the opposing inclined surfaces, the locking mechanism is essentially self-engaging and can distribute the load more uniformly along the longitudinal direction of the interface between the male and female parts.

Claims

1. A locking mechanism comprising complementary male and female parts having longitudinal axes, the locking mechanism having a first end on the load side and a second end on the tensile side, The male portion includes a rigid rod having a grooved outer surface, each groove having a load-side flank and an opposing flank, the load-side flank and the opposing flank having different angles to each other, and the load-side flank being substantially perpendicular to the longitudinal axis of the locking mechanism assembly. The female portion includes an outer sleeve, the outer sleeve surrounds a plurality of grooved engaging members, the plurality of grooved engaging members have a grooved surface and opposing inclined surfaces, the outer sleeve has a tapered inner bore whose cross-section decreases toward the load-side end, the tapered inner bore includes an inclined surface, The male portion penetrates the female portion, and the plurality of grooved engaging members are arranged radially inward on the inclined surface, between the male portion and the outer sleeve. The load is transmitted from the male part to the plurality of grooved engaging members, and from the plurality of grooved engaging members to the outer sleeve, and the load is transmitted from the plurality of grooved engaging members to the outer sleeve only at the interface between the inclined surfaces of the plurality of grooved engaging members and the inclined surfaces of the outer sleeve. A locking mechanism characterized by the following features.

2. The locking mechanism according to claim 1, comprising at least four grooved engaging members.

3. The locking mechanism according to claim 1 or 2, wherein the plurality of grooved engaging members are arranged in a row.

4. The locking mechanism according to any one of claims 1 to 3, wherein the plurality of grooved engaging members are movable along the inclined surface between an engaged position and a non-engaged position.

5. The engagement position corresponds to the position where the plurality of grooved engagement members engage with the grooved outer surface of the male part. The locking mechanism according to claim 4, wherein the disengaged position corresponds to a position in which the male portion is movable along the longitudinal axis of the locking mechanism.

6. The locking mechanism according to claim 4 or 5, wherein in the non-engaged position, the plurality of grooved engaging members are positioned radially outward and axially away from the load-side end with respect to the engaging position.

7. The locking mechanism according to any one of claims 4 to 6, wherein the plurality of engaging members are biased to the engaging position.

8. The locking mechanism according to any one of claims 1 to 7, wherein the load-side flank of the groove of the male part is at an angle of more than 70° with respect to the longitudinal axis of the locking mechanism.

9. The locking mechanism according to any one of claims 1 to 8, wherein the load-side flank of the groove of the male part is at an angle of more than 80° with respect to the longitudinal axis of the locking mechanism.

10. The locking mechanism according to any one of claims 1 to 9, wherein the opposing flanks of the grooves of the male part are at an angle of 10° to 60° with respect to the longitudinal axis of the locking mechanism.

11. The locking mechanism according to any one of claims 1 to 10, wherein the grooves of the male part and the plurality of engaging members have the same profile.

12. The locking mechanism according to any one of claims 1 to 11, wherein the tapered bore is frustoconical in shape.

13. The locking mechanism according to any one of claims 1 to 11, wherein the tapered bore is truncated pyramidal.

14. The locking mechanism according to claim 13, wherein the tapered bore has at least six surfaces.

15. The locking mechanism according to claim 14, comprising six grooved engaging members.

16. The locking mechanism according to any one of claims 13 to 15, wherein the number of grooved engaging members is equal to the number of faces of the tapered bore.

17. The locking mechanism according to any one of claims 1 to 16, wherein the inclined surfaces of the plurality of grooved engaging members and the corresponding inclined surfaces of the outer sleeve have the same pitch.

18. The locking mechanism according to any one of claims 1 to 17, wherein the inclined surface of the outer sleeve is at an angle of 10° to 40° with respect to the longitudinal axis.

19. The locking mechanism according to any one of claims 1 to 18, wherein the inclined surface of the outer sleeve has a single pitch.

20. The locking mechanism according to any one of claims 1 to 19, wherein the inclined surface of the outer sleeve is longer than the inclined surfaces of the plurality of grooved engaging members.

21. The locking mechanism according to any one of claims 1 to 20, wherein the locking mechanism is provided inside the connector.

22. The locking mechanism according to claim 21, wherein the connector is a connector for use underwater.

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