Patent Publication Number: US-10315730-B2

Title: Marine anchor

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This is a utility patent application which claims the benefit of PCT/NZ2016/050072, filed on May 9, 2016, the contents of which are hereby incorporated by reference in its entirety. 
     FIELD OF INVENTION 
     The invention relates to an anchoring device for anchor floating marine structures. 
     BACKGROUND 
     Some structures are designed to float on water and be anchored to a fixed point. The fixed point may be a fixed anchor point on a sea floor, river bed or lake bed or may be a point on the shore or even another floating structure. Examples of a floating structures include buoys, mussel farms or recreational rafts fixed to the sea floor. 
     Floating structures are subject to forces that alter the distance between the structure and the fixed anchor point. For example structures in the sea are subject to wind, waves and tides. Structures in a lake are subject to wind and waves. Anchoring devices need to have some flexibility to allow for natural movement of the floating structure. 
     The term “comprising”, if and when used in this document, should be interpreted non-exclusively. For example if used in relation to a combination of features it should not be taken as precluding the option of there being further unnamed features. 
     SUMMARY OF THE INVENTION 
     In broad terms in one aspect the invention comprises an anchoring device comprising: an anchor comprising
         a substantially non-conducting housing including a series of collet apertures;   flexible strands;   collets; and   a water bed engaging part;       

     where each collet is engaged with a respective one of the flexible strands to secure it in a respective one of the collet apertures of the housing, the water bed engaging part being located on the bed of a body of water with the strands extending upwards to secure an item at or near the surface of the water, the strands being able to expand and contract lengthwise to resist breaking due to pulling of the item. 
     Preferably the anchor further comprises a second non-conducting housing including a series of collet apertures where each collet receives an end of a flexible strand and secures it in a respective one of the collet apertures of the housing and each flexible strand extends between the two housings. 
     Preferably the anchor further includes a connector releasably received in an aperture of the housing, the connector being attached to the anchor. 
     Preferably the connector is a mooring pin having a narrower portion passing through the aperture of the housing and having a portion wider than the aperture of the housing. 
     Preferably the mooring pin has an aperture in its wider portion. 
     Preferably the portion of the mooring pin that extends through the housing has at least one aperture. 
     Preferably a non-elastic strand is connected to the mooring pin through the aperture of the mooring pin. 
     Preferably the collets are substantially cylindrical. 
     Preferably one end of each collet is provided with a flange. 
     Preferably each collet is formed in two pieces. 
     Preferably the collets are formed from nylon. 
     Preferably the housing is formed from acetal. 
     In a further aspect of the invention there is an anchor comprising
         a non-conducting housing including a series of collet apertures and a housing aperture;   a first mooring pin adapted to pass through the housing aperture;   a second non-conducting housing including a series of collet apertures and a second housing aperture;   a second mooring pin adapted to pass through the second housing aperture;   flexible strands;   collets; and   a water bed engaging part;       

     where each collet is engaged with a respective one of the flexible strands to secure it in a respective one of the collet apertures of the housing and of the second housing, the water bed engaging part being located on the bed of a body of water with the strands extending upwards between housings to secure an item at or near the surface of the water, the strands being able to expand and contract lengthwise to resist breaking due to pulling of the item; 
     each pin having a narrower portion passing through the respective housing aperture and a portion wider than the respective housing aperture having an aperture in that wider portion, a non-elastic strand attached to each aperture in each wider portion so that each strand extends between the housings to restrict the extent of expansion of the strands. 
    
    
     
       DRAWINGS 
       The invention will be described in more detail with reference to the accompanying drawings in which: 
         FIG. 1  shows a marine anchor of the invention in use in a marine setting; 
         FIG. 2A  is a top perspective view of a housing, anchor pin and collets; 
         FIG. 2B  is a bottom perspective view of a housing, anchor pin and collets; 
         FIG. 3A  is a perspective view of an anchor pin; 
         FIG. 3B  is a perspective view of the collets; 
         FIG. 3C  is a perspective view of the housing; 
         FIG. 3D  is a perspective view of a washer; 
         FIG. 4  is cutaway view of the marine anchor; 
         FIG. 5A  is a top view of a collet; 
         FIG. 5B  is a side view of a collet piece; 
         FIG. 6A  is a perspective view of another anchor pin; 
         FIG. 6B  is a perspective view of collets; 
         FIG. 6C  is a perspective view of another housing; 
         FIG. 6D  is a perspective view of a washer; 
         FIG. 7A  is a top perspective view of a housing, anchor pins and collets; 
         FIG. 7B  is a bottom perspective view of a housing, anchor pins, collets and washer; 
         FIG. 8  is a perspective view of another housing; 
         FIG. 9  is a perspective view a collet housing with collets and an anchor pin; 
         FIG. 10  is an exploded view of a collet housing; and 
         FIG. 11  is a cut away view of a collet housing and anchor pin. 
     
    
    
     DETAILED DESCRIPTION 
     Some preferred forms of the invention will now be described by way of example. It should be understood that these are not intended to limit the scope of the invention but rather to illustrate optional embodiments. 
     It should be noted that the marine anchor is not limited to sea environments. The marine anchor can be used in any suitable environment including the sea, rivers, lakes etc. 
       FIG. 1  shows a marine anchor of the invention in use in a marine setting. The marine anchor includes housing  1 , anchor pin  2 , collets (not shown in this figure) and flexible strands  3 . Flexible strands  3  extend through the collets and thereby through the housing  1 . As shown in  FIG. 1  housing  1  may be provided at each end of the anchor. 
     Anchor pin  2  is adapted to pass through housing  1  (shown in more detail in  FIGS. 2A and 2B ). One end of anchor pin  2  includes an aperture. In use a connector may be positioned through the aperture and connected to further components. As can be seen in  FIG. 1  bottom anchor pin  2  is adapted to be connected to shackle  6 . Swivel  8  can then be connected to shackle  6 . Another part of swivel  8  can be connected to screw anchor  7  through second shackle  6 . Swivel  8  allows rotation of all parts above the swivel. 
     As shown in  FIG. 1 , screw anchor  7  is attached to the sea bed  14 . In use the marine anchor can be connected to any suitable point. In most cases this will be a fixed point either underwater or at the water line. An alternative form of fixing is shown in  FIG. 1  where mooring block  9  is shown on the sea bed. 
     The end of anchor pin  2  that extends through housing  1  may be connected to a non-elastic strand that extends between the housings. The non-elastic strand may be a rope for example. In embodiments where a non-elastic strand is provided the non-elastic strand will typically be longer than the elastic strands when the elastic strands are not under tension. Having the non-elastic strand longer than the elastic strands when the elastic strands are not under tension allows the elastic strands to elongate up to the length of the non-elastic strand. This provides a limit on the elongation of the elastic strands. In one embodiment the non-elastic strand may be a braided by-pass rope. 
     In some embodiments the marine anchor of the invention may extend all the way between the fixed anchor and the floating structure. In other embodiments the marine anchor may be attached to a non-elastic portion between the fixed anchor and floating structure.  FIG. 1  shows the marine anchor of the invention attached to a non-elastic portion comprising lift buoy  10  and rope  11 . The lift buoy prevents the marine anchor coming into contact with the ground materials during extreme low tides. Rope  11  may be any suitable rope. 
     Lifting buoy  10  is attached to the housing  1  through anchor pin  2  using shackle  5 . One end of the rope  11  is attached to lifting buoy  10  and the other end is attached to a floating structure  12 . In  FIG. 1  floating structure  12  is a buoy that floats on the sea surface. 
     As can be seen in  FIG. 1  the marine anchor allows the floating structure to move on the water surface in response to forces acting on the floating structure. The elastic strand(s) in the marine anchor will act to move the floating structure back to a position substantially above the fixed anchor when no forces are acting on the floating structure. 
       FIGS. 2A and 2B  show perspective view of a housing  1  with anchor pin  2  in place and a plurality of collets  15 . 
     To survive in a marine environment housing  1  is formed form non-corrosive material. In preferred embodiments housing  1  is formed from a non-corrosive material such as acetal. Forming the housing from a non-corrosive material such as acetal provides good resistance to corrosion from salt water and durability. The housing includes a number of first apertures that extend through the housing and are designed to house collets  15 . There are six collet apertures shown in  FIGS. 2A and 2B  but this number may differ. For example  FIGS. 6A and 6B  show a housing with eight collet apertures. The number of collet apertures may vary depending on the intended use of the marine anchor. As an example marine anchors for floating jetties may require more collet apertures than a marine anchor for a single small buoy. The invention is not limited by the number of collet apertures. Further, the collet apertures need not be provided in a circle around a central aperture. For example, two circles of collet apertures could be provided. Alternatively the collets could be provided in a single row. 
     Housing  1  is shown as substantially cylindrical but this should not be seen as limiting. Any suitable shape housing may be used. 
     As can be seen in  FIGS. 2A and 2B  collets  15  are designed to sit within the apertures of the housing. In preferred embodiments the collets are formed from nylon but alternatively may be formed from any suitable material. 
     Anchor pin  2  extends through housing  1  through a second aperture. In some embodiments washer  16  is provided for the bottom of housing  1  around the second aperture. 
       FIG. 3A  shows one embodiment of anchor pin  2  in more detail. Anchor pin  2  includes wider portion  17  that is dimensioned to be too large to pass through the anchor pin aperture in the housing. Anchor pin  2  also includes narrower portion  18  that is dimensioned to pass through the anchor pin aperture in the housing. The wider portion  17  of anchor pin  2  includes at least one aperture  19 . The aperture  19  is dimensioned to allow a fixing device (such as a shackle like that shown in  FIG. 1 ) to be attached to the anchor pin and further attached to other components. The other components may include further fixing components, non-elastic strands or any suitable components. 
     Although aperture  19  is shown to be circular in  FIG. 3A  this should not be seen as limiting. In other embodiments the aperture may be oval, elliptical or any other suitable shape. 
     The narrower portion of anchor pin  2  includes at least one aperture  20 . The aperture is dimensioned to allow a fixing device to be attached to the anchor pin and further components. The anchor pin shown in  FIG. 3A  may include a second aperture  21 . In some embodiments aperture  21  is designed to hold a bolt to prevent anchor pin  2  from sliding out of housing  1 . In preferred embodiments the anchor pin is formed from a non-corrosive metal. Examples of suitable metals include stainless steel and titanium. 
       FIG. 3D  shows a washer  16  that may be placed around the anchor pin aperture in housing  1 . If a bolt (or the like) is used with anchor pin  2  washer  16  may prevent or limit damage to the housing from the bolt. Ideally the central aperture of the washer has the same cross-section as the anchor pin aperture in the housing. 
       FIG. 3B  shows some collets  15 . Collets  15  include a central aperture that extends through the collet and is parallel to the collet housing aperture when the collet is in the housing. In preferred embodiments the collets are substantially cylindrical. As can be seen in  FIG. 3B  the collets may have a larger diameter at one end of the collet. In this embodiment a mating section is formed in the housing collet apertures. This embodiment allows the collets to be slid into the housing in only one direction to fit snugly into the collet apertures of the housing. 
     The internal aperture of the collet may be substantially cylindrical. As shown in  FIG. 3B  (and  FIG. 5B ) the internal aperture of the collet may be bevelled at each end. Bevelling the collet helps to prevent wear on elastic strands when positioned in the collet. 
       FIG. 4  shows a marine anchor of the invention with two housings, two anchor pins and a plurality of collets and elastic strands. Both housings contain the same number of collets and collet apertures. As can be seen in  FIG. 4  washer  16  is in place around anchor pin  2  and between housing  1  and bolt  22 . Bolt  22  is positioned through aperture  21 . 
     A plurality of flexible elastic strands  3  extend between the collets of the two housings. Each elastic strand extends through a collet at each end. Ideally the elastic strands are formed from rubber. In some embodiments the elastic strands are hollow. The elastic strands can be elongated. As the strands are elongated the diameter of the strand decreases. 
     The lengths of the elastic strands will be determined by the distance the marine anchor needs to span 
     In  FIG. 4  the elastic strands  3  are not elongated. As can be seen in  FIG. 4  the diameter of the non-elongated elastic strands is wider than the smallest internal diameter of the collets. This means that the portion of the elastic strands within the collet is exerting a force on the inside the collet trying to expand the collet against the housing. As the smallest internal diameter of the collet is less than the non-elongated diameter of the elastic strand, the elastic strand cannot slip out of the collet. In preferred embodiments of the invention the diameter of the elastic strand when it is not elongated is larger than the diameter of the collet apertures in the housing 
       FIG. 4  also shows a non-elastic strand  4  extending between apertures  20  of the anchor pins  2 . Non-elastic strand  4  may be connected to through aperture  20  by any suitable means. Non-elastic strand  4  will generally be longer than the un-elongated elastic strands. The longest the elastic strands should be able to be elongated is such that the smallest allowable diameter of the elongated elastic strand is greater than the smallest internal diameter of the collet. The length of the non-elastic strand may be such to prevent the elastic strands from elongating too far 
     To insert an elastic strand into a collet the end of the elastic strand is elongated causing the diameter to decrease. The strand is fed through the housing. The collet can then be slipped around the end of the elastic strand holding the shape of the elastic strand within the collet.  FIGS. 5A and 5B  show a top view and a side view of a collet respectively. In preferred embodiments the collets are formed of two semi-cylindrical pieces as shown in  FIG. 5B . When the collets are formed in two (or more) pieces then the collets can be more easily placed around the elongated elastic strand. Once the collet pieces are in place the collet can be slid into the housing and the elongated strand unstretched. 
       FIG. 5B  shows one piece of a two piece collet (or the cross-section of a single piece collet). As can be seen in  FIG. 5B  the collet has a smallest internal diameter  24  sized to be smaller than the non-elongated diameter of the elastic strands. The collet also has external diameter  23  sized to fit snugly into the collet apertures of the housing. The collet may have wider flange  25  shaped to fit into a corresponding portion of the collet aperture in the housing. The wider flange part of the collet and corresponding portion of the collet aperture allows the collet to be positioned into the aperture in only one way. In use the flange side of the collets are positioned with the ends of the elastic strands through them so that as the strands stretch the flange prevents the collets from pulling through the collet apertures. 
     The collets may also be provided with bevels  26  and  27  at each end of the collet aperture. The collet bevels help to reduce wear on the elastic strands. 
     In preferred embodiments the collets extend all the way through the collet apertures in the housing. This prevents wear on the elastic strands from the housing. 
     In one example embodiment the internal diameter of the collets are 27 mm. When relaxed the diameter of the flexible elastic strands is 40 mm. To fit the collets to the elastic strands the elastic strands need to be stretched 300% to reduce the diameter of the strands to the internal diameter of the collets. Once the collets are in place in the housing the strands can be relaxed. 
       FIGS. 6A  to D and  FIGS. 7A and 7B  show housings with eight collets and collet housings. It should be appreciated that any number and arrangement of collets and collet housings can be used. 
       FIG. 8A  shows another embodiment of collet housing. This housing has eight apertures for receiving collets as well as a central aperture for an anchor pin. As can be seen in  FIG. 8A  the outside of the collet housing is not cylindrical but rather is shaped around the collet apertures. Any suitable collet housing shape may be used. 
       FIG. 9  shows a two-piece collet housing with  10  collets. The housing has first piece  28  and second piece  29 . The first and second pieces of the collet housing are held together by fixing means  30 . The collets  31  are surrounded by collet sleeves  32 . Anchor pin  33  extends from either side of a central aperture in the housing. 
       FIG. 10  is an exploded view of a collet housing, collets, anchor pin and fastening means similar to the housing of  FIG. 9 . The collet housing of  FIG. 10  is configured to receive nine collets. The collet housing comprises first piece  28  and second piece  29 . The two pieces of the collet housing are connected together by fixing means  30 . The fixing means may be screws or any other suitable device. Collets  31  can be surrounded by collet sleeves to improve the durability of the collets and the flexible strands (not shown) that extend through the collets when the anchor is in use. Anchor pins  33  extend through both sides of the collet housing and into central cylinder  34 . Anchor pins  33  are shown as a two piece anchor pin. Each piece of the anchor pin is placed into the central aperture through the housings  28  and  29 . When the housings are connected by the fixing means  30  the anchor pin is locked and place and cannot be pulled out of the collet housing. 
       FIG. 11  is a cut away view of a collet housing showing a two piece anchor pin as used in  FIGS. 8 to 10 . 
     In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word “comprise” or variation such as “comprises” or “comprising” is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention. 
     While some preferred aspects of the invention have been described by way of example it should be appreciated that modifications and improvements can occur without departing from the scope of the invention.