Abstract:
A folding anchor having a shank formed in two pieces and joined together with a keyhole fitting, and, upon pivoting the upper shank abuttingly overlies the lower shank. The fluke assemblies are pivotally connected via a coupling assembly at the lower end of the shank, the coupling assembly including a retaining member for pivotal coupling to the fluke assemblies and a slide block member having a passage for receiving the retaining member therein, displacement of one relative to the other enabling pivoting of the fluke assemblies between folded and unfolded positions, this being accomplished by 90 degree pivoting of the fluke assemblies about first axes generally parallel to the longitudinal axis of the shank, whereby the two flukes may be rotated toward each other into proximate facing relation, or away from each other into alignment. The interconnection of the shank with the retaining member, along with the dimensioning and configuration of the slide block member, enables a limited amount of angular movement on a second axis orthogonal to the longitudinal axis of the shank relative to the flukes to facilitate engagement and disengagement relative to the sea bed. The flukes are generally right triangularly configured and formed of plate metal, the shank portions are formed of metal bar stock, and the balance of the anchor is formed from readily available metal stock assembled with conventional metal fabrication methods, such as welding and bending.

Description:
BACKGROUND OF THE INVENTION 
     The background of the invention will be discussed in two parts. 
     1. Field of the Invention 
     This invention relates to anchors, and more particularly to a folding anchor for small watercraft. 
     2. Description of the Prior Art 
     Anchors generally include a shank with a fluke arrangement at one end of the shank, the other end of the shank being connected to an anchor chain. Generally, the flutes are attached to the shank to permit a limited amount of angular movement. When the anchor is lowered into the sea, the flukes engage the sea bottom, with the shank extending at an angle to the sea bottom in a forward direction, that is, in the direction of the boat. For release of the anchor from engagement with the sea bottom, the boat direction is reversed to provide a direction of force thereon opposite to the direction of engagement of the flukes. To facilitate release, some anchors have been formed with two-piece shanks coupled for limited pivotal movement at a point intermediate the ends of the overall shank. 
     One such anchor is disclosed in U.S. Pat. No. 103,205, entitled &#34;Anchor&#34;, such patent issuing on May 17, 1870 to Law. The anchor of this patent includes a two piece shank, with the upper shank piece being pivotable through a limited angle relative to the lower shank, to which is attached a fluke assembly, which is likewise pivotable through a limited angle. 
     Another anchor construction is shown and described in U.S. Pat. No. 2,720,184, entitled &#34;Articulated and Self-Locking Shank for Anchor&#34;, issued to Polenz on Oct. 11, 1955, such patent disclosing an anchor with a two-piece shank, the interconnection of the two pieces being by means of a keyhole slot engaged by a block member. In one position, the block is locked within the narrow neck of the slot with the two shank pieces in axial alignment. When force is exerted by the anchor chain in an opposite direction, tho upper shank moves rearwardly relative to the lower shank until the block is in the enlarged portion of the keyhole, thereby permitting pivoting to facilitate release of the anchor from the sea bottom. 
     Another example of an articulated anchor structure is disclosed in U.S. Pat. No. 3,263,642, entitled &#34;Boat Anchor&#34;, which issued to Wilson on Aug. 2, 1966, the anchor including a unitary fluke formed of plate metal with first and second symmetrically arranged slots with a common origin. The shank is formed as a yoke with a bar engaging the slot at the origin, with the bolt able to traverse either slot to facilitate removal of the flukes fro engagement with the sea bed. 
     Some anchors have been constructed to permit folding of the flutes and stock arms against the shank, such as shown in U.S. Pat. Nos. 3,215,111 and 3,807,340, the former being issued to McDaniel on Nov. 2, 1965, and the latter being issued to Diorio et al on Apr. 30, 1974. In both patents, the anchors are of the conventional Navy type and have the stock arms pivotally attached to the shank adjacent a first end thereof, with the flukes pivotally attached to the shank adjacent the other end thereof, with the plane of pivoting of the stock arms perpendicular to the plane of pivoting of the flukes. The Diorio anchor includes a spring member encircling the rod-shaped shank to spring load the stock arms to the ope position. 
     An anchor including flukes which may be physically detached from the shank for storage is shown and described in U.S. Pat. No. 3,822,666, entitled &#34;Anchor&#34;, which issued to Blomberg on July 9, 1974. 
     The last three patents enumerated above concern themselves with anchors of the folding type, with the Blomberg and McDaniel anchors being more suited for small pleasure craft usage. The flukes formed of plate metal, as shown in Blomberg, are of widespread use in small craft anchors of recent vintage. Although the Blomberg anchor permits detachment of the flukes for storage and transportation by removal and reattachment of bolts, the anchor should be reassembled prior to casting off, thereby eliminating any storage space advantage while at sea. On the other hand, while the McDaniel anchor permits folding to a relatively small overall configuration, the length of the folded anchor is the same as the length of the shank. Furthermore, such Navy anchors do not have widespread acceptance among small pleasure craft users. 
     In accordance with an aspect of the invention, it is accordingly an object of the invention to provide a new and improved foldable small craft anchor. 
     SUMMARY OF THE INVENTION 
     The foregoing and other objects of the invention are accomplished by providing a folding anchor, having a shank formed in two pieces and joined together with a keyhole fitting, and, upon pivoting the upper shank abuttingly overlies the lower shank. The fluke assemblies are pivotally connected via a coupling assembly at the lower end of the shank, the coupling assembly including a retaining member for pivotal coupling to the fluke assemblies and a slide block member having a passage for receiving the retaining member therein, displacement of one relative to the other enabling pivoting of the fluke assemblies between folded and unfolded positions, this being accomplished by 90 degree pivoting of the fluke assemblies about first axes generally parallel to the longitudinal axis of the shank, whereby the two flukes may be rotated toward each other into proximate facing relation, or away from each other into alignment. The interconnection of the shank with the retaining member, along with the dimensioning and configuration of the slide block member, enables a limited amount of angular movement on a second axis orthogonal to the longitudinal axis of the shank relative to the flukes to facilitate engagement and disengagement relative to the sea bed. The flukes are generally right triangularly configured and formed of plate metal, the shank portions are formed of metal bar stock, and the balance of the anchor is formed from readily available metal stock assembled with conventional metal fabrication methods, such as welding and bending. 
     Other objects, features and advantages of the invention will become readily apparent from a reading of the specification, when taken in conjunction with the drawings, in which like reference numerals refer to like elements in the several views. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a foldable anchor according to the invention in its ready-for-use position; 
     FIG. 2 is a perspective view of the foldable anchor of FIG. 1, shown in its folded position; 
     FIG. 3 is a enlarged partial top view of the anchor of FIG. 1 depicting, in dotted lines, the position of the fluke assemblies in the folded position; 
     FIG. 4 is an enlarged partial cross-sectional view of the anchor of FIG. 1, as viewed along line 4--4 of FIG. 3; 
     FIG. 5 is an enlarged partial cross-sectional view of the anchor of FIG. 1, as viewed along line 5--5 of FIG. 4; and 
     FIG. 6 is a partial perspective view depicting the lower end of the shank of the anchor of FIG. 1 connected to a retainer member. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the drawings, and particularly to FIGS. 1 and 2, there is shown a preferred embodiment of an anchor, generally designated 10, in accordance with the invention, the anchor 10 including a shank assembly, generally designated 20, two fluke assemblies, generally designated 30 and 30&#39;, and a coupling assembly, generally designated 40. 
     The shank assembly 20 is formed of first and second shank portions 21 and 22, each of which is formed of generally elongate metallic bar stock, and preferably double zinc coated for corrosion resistance. The shank portion 21 is the main, or lower shank portion, which is provided at one end 21a thereof with a keyhole slot 23 (shown in dotted lines in FIG. 5), having a circular portion 23a on the longitudinal centerline thereof, and a narrow necked portion 23b aligned with the centerline. The other end 21b of the shank portion 21 is provided with a generally circular opening 24, which is formed, such as by drilling in the metal bar stock. As shown, there is a generally L-shaped cut line, designated 25, of which one leg is tangential to the circumference of the opening 24 in a direction generally parallel to a long side of the shank portion 21. The other leg is cut perpendicular to that long side to intersect the first leg, as a consequence of which thus severed strip of metal, designated 26, may be bent outwardly relative to the aperture 24 (as shown in dotted lines in FIG. 6) for providing access for a pivot axis member into the opening 24, after which the strip 26 is then bent back to the position depicted in FIG. 5, encircling a portion of a retaining member 41, as will be hereafter described. 
     The other, or upper shank portion 22 is smaller in length than the upper shank portion 21, and is provided with a first enlarged aperture 27 at the one end 22a thereof, which aperture 27 is configured for connection to an anchor chain (not shown). A second smaller aperture (not shown) is provided adjacent the other end 22b of the shank portion 22 at a position displaced from the extreme end thereof. Both apertures 27 and 28 have the centers thereof on the longitudinal centerline of the shank portion 22. Pivotable interconnection of the upper and lower shank portions 21 and 22 is accomplished by means of a button head rivet member 29 passed through and affixed within the aperture of upper shank portion 22 and through the keyhole slot 23 of the lower shank portion 21. 
     The rivet member 29 has a keying shaft portion 29a with a generally rectangular configuration (See FIG. 5), the width of which is generally equal to the width of the necked portion 23b of the keyhole slot 23, and the length of which is slightly smaller than the diameter of the circular portion 23a of the keyhole slot 23. The shank portions 21 and 22 are thus locked together with the rectangular rivet shaft 29a within the necked portion 23b of the keyhole slot 23, and are pivotable relative to one another with the shaft 29a within the circular portion 23a of the keyhole slot 23. As shown in FIGS. 1 and 5, the distance between the lower aperture of the upper shank portion 22 relative to the end 22b thereof enables a significant amount of overlapping surface area at the junction of the two shank portions in the extended or unfolded position shown in FIG. 1, to provide good frictional engagement and structural support. 
     Referring to FIGS. 1 and 2, the fluke assemblies 30 and 30&#39; are generally identically dimensioned and are configured in mirror image relation, that is, a left and right assembly. However, the parts from which the two assemblies are fabricated are identical, and include flukes 31 and 31&#39;, which are formed of plate metal, preferably zinc-coated, with right triangular configuration including short side 31a (31a&#39;), long side 31b (31b&#39;) and hypotenuse side 31c (31c&#39;). The short sides 31a, 31a&#39; are suitably attached to fluke support members 32, 32&#39;, such as by welding. To provide rigidity, the edges of the long sides 31b, 31b&#39; of the flukes 31, 31&#39; are bent at right angles to the plane of the flukes 31, 31&#39;. The support members 32, 32&#39; are formed of tubular metal bent into an L-shaped configuration, with a long leg 32a, 32a&#39; and a short leg 32b, 32b&#39; (See also FIGS. 3 and 4), the side 31a, 31a&#39; of the fluke 31, 31&#39; being secured to the long leg 32a, 32a&#39;, with the plane of the fluke 31, 31&#39; lying in a plane which includes the axial centerline of the long leg 32a, 32a&#39;, as well as the axial centerline of the short leg 32b, 32b&#39;. 
     Referring also to FIGS. 3 through 6, the coupling assembly 40 interconnects the shank assembly 20 and the fluke assemblies 30 and 30&#39;, and for this purpose is provided with a fluke shaft retaining member 41 configured for being received with a slide block member 50. The fluke shaft retaining member 41 is formed from a generally rectangular metal plate having opposite sides bent to form first and second generally tubular cylinders 42 and 43, interconnected by a central web portion 44. The inner diameter of cylinders 42 and 43 are identical, and are slightly greater than the outer diameter of the short legs 32b, 32b&#39; of the fluke support members 32, 32&#39;. An upper edge of the web portion 44 is notched to form a generally centrally disposed slot 44a in axial alignment with an aperture 45 therebelow in the web portion 44. 
     As shown in FIG. 6, the metal strip 26 of the lower shank portion 21 is bent outwardly and inserted through the aperture 45 of web 44 of fluke retaining member 41, after which it is bent back to its original position, whereby the small portion of the web 44 intermediate the slot 44a and the aperture 45 are received within the aperture 24 of shank portion 21, as shown in FIG. 5. Thus the lower shank portion 21 is pivotably attached to the fluke retaining member 41. 
     The slide block member 50 is a rectangularly configured box-shaped member which is double open-ended to form a rectangular opening or passage 51 therethrough, the passage 51 being defined by opposing front and back walls 50a and 50b and interconnecting side walls 50c and 50d (See FIG. 3). The dimension between opposing facing surfaces of the front and back walls 50a and 50b is slightly greater then outer diameter of the cylinders 42, 43, while the dimension between the opposing facing surfaces of the side walls 50c and 50d is slightly greater than the dimension between opposite outer edges of the cylinders 42, 43. Thus, the passage 51 is dimensioned for slidably receiving therein, in snug fitting relationship, the fluke retaining member 41. 
     The upper edges of the opposing front and back walls 50a and 50b are provided with generally identical centrally disposed rectangular cutouts 53, 54, in aligned relation, the width of the cutouts 53, 54 being slightly greater than the thickness of the lower shank portion 21 of the shank assembly 20. On the external surfaces of the front and back walls 50a and 50b, first and second shank pivot limiting blocks 55, 56 are secured, such as by welding, across the opening of the cutouts 53, 54, respectively, at a distance below the upper edges of the walls 50a, 50b, and slightly above the lower edge of the cutouts 53, 54 (See, particularly, FIGS. 4 and 5). As will be described, with the shank assembly 20 and the fluke assemblies 30, 30&#39; attached by means of the coupling assembly 40, the shank portion 21 pivoting is thus restricted to an angle of +/-15 degrees (as shown in dotted-lines in FIG. 5) relative to the plane of the web portion 44 of the fluke retaining member 41. 
     The lower edge of the front wall 50a is provided with three cutouts (See FIGS. 1 and 5), a centrally disposed elongate slotted cutout 57, with two somewhat larger, semicircularly configured cutouts 58, 59 symmetrically arranged on opposite sides of the central cutout 57. The diameter or width of the cutouts 58 and 59 is generally equal to the outer diameter of the fluke support members 30, 30&#39;. The lower edges of side walls 50c and 50d likewise have aligned cutouts 70, 71 (See FIGS. 1 and 4), which are configured identically to the cutouts 58, 59. The distance between the centers of the cutouts 70, 71 is generally the same as the distance between the axial centerlines of the cylinders 42, 43, and the side cutouts 70, 71 have the centers thereof positioned centrally relative to the depth of the side walls 50c, 50d. The lower portion of the rear wall 50b is provided with a cutout 72 in alignment with the front slotted cutout 57, with an aperture 73 immediately thereabove. A fastening member 75 is provided, the fastening member 75 being formed from a threaded rod having a diameter slightly smaller than the diameter of the aperture 73, as well as the width of the cutout 57. One end of the rod is threaded, such as at 75a, and the other end is passed through the aperture 73, and then bent into a loop 75b (See FIG. 5), the opening of which has passing therethrough the necked portion of the rear wall 50b intermediate the aperture 73 and the adjacent cutout 72. The fastening member 75 is thus captively and pivotally attached to the centermost part of the lower edge of the rear wall 50b. In this position, the threaded end 75a passes into the elongate cutout 57, whereupon a suitable nut member 77 may be threaded thereon. To facilitate tightening and loosening, the nut member 77 may be provided as a winged nut member. 
     The anchor 10 is assembled in the following manner. The upper and lower shank portions 21 and 22 are connected by means of the rivet member 29 as previously described. The fluke members 31, 31&#39; are suitably attached to the fluke support members 32, 32&#39; as described. The lower end of the lower shank portion 21 is pivotably secured to the shank retaining member 42 as described (See FIG. 6). The fastening member 75 is pivotally attached to the rear wall 50b of the slide block 50 (See FIG. 5). The shank retaining member 41 is then inserted into the passage 51 of the slide block 50. The width of the shank portion 21 is slightly less than the width of the passage 51, and the length of the web portion 45 of the shank retaining member 41, in the insert direction is less than the length of the passage 51 in the direction of insertion (See FIGS. 3 and 4). The plane of the web portion 45 lies midway between the front and rear walls 50a, 50b, with the spacing between the web 45 and an adjacent interior wall being slightly more than the diameter of the rod from which the fastening member 75 is formed (See FIGS. 3 and 5). 
     The short leg 32b of fluke 30 is then inserted from the bottom into the cylinder 42 until the free end thereof protrudes slightly above the cylinder 42. A washer member 78 is then suitably affixed (See FIGS. 3 and 4), such as by welding, to the upper free end of the leg 32b, thereby enabling pivoting of the fluke assembly 30 about an axis through the axial centerline of cylinder 42, while preventing relative displacement in the direction of the axial centerline of the cylinder 42. The washer member 78 has an outer diameter approximately the same as the outer diameter of the cylinder 42, thereby captively retaining the leg 32b therein. The right fluke assembly 30&#39; is then attached in the same manner with the washer member 79 secured to the free end of short leg 32b&#39; after insertion into the right cylinder 43. 
     In the ready-for-use position shown in FIG. 1 (See also FIGS. 3 and 4), the shank portions 21 and 22 are extended and the fluke assemblies 30 and 30&#39; are pivoted or extended until the long legs 32a and 32a&#39; of fluke support members 32, 32&#39; are in axial alignment. The retaining member 41 is in the solid line position shown in FIG. 4, with the legs 32a, 32a&#39; coactingly recessed within the cutouts 70, 71, respectively, of the sidewalls 50c, 50d. The fastener member 75 has the shaft thereof in abutting engagement with the lower edge of web portion 44 of retaining member 41, with the threaded end 75a within slotted cutout 57, and the nut 76 tightened to secure the parts in position, as also shown in solid lines in FIG. 5. 
     For storage, as shown in FIG. 2, the shank portions 21 and 22 are pivoted into overlying relation, with the upper shank portion 22 being slightly smaller in length to clear the slide block 50 of the coupling assembly 40. To move the parts into this position, the nut 76 is loosened, allowing the fastener member 75 to pivot downwardly to the dotted line position shown in FIG. 5. The slide block 50 is displaced upwardly to the dotted line position shown in FIG. 4 relative to the shank retaining member 41 until the upper edges of the legs 32a and 32a&#39; clear the lower edges of the sidewalls 50c and 50d, whereupon, the fluke assemblies 30, 30&#39; may be rotated forwards toward each other until the legs 32a, 32a&#39; are in alignment with the cutouts 58, 59, respectively, in the front wall 50a (See also FIG. 3). in this position, the fluke assemblies 30, 30&#39; are in facing relation and, as shown in FIG. 3, the pivot stop block 55 is notched at the corners thereof to receive therein the angled edges 31b, 31b&#39; of the flukes 31, 31&#39;, respectively. 
     The slide block member 50 is then displaced relative to the retaining member 41 until member 41 is retracted into passage 51 of slide block 50. The fastener member 75 is then pivoted from the dotted line position to the solid line position shown in FIG. 5 into the slotted cutout 57, and the nut 76 is tightened. The threaded end 75a of the fastener member 75 is sufficient in length that the member 75 may be rotated into and out of engagement with the slotted cutout 57, without totally removing the nut 76, thus enabling the fastener 75 and nut 76 to be held captively on the slide block member 50. 
     With the fluke assemblies 30, 30&#39; rotated into aligned generally parallel relationship as shown in FIG. 2, that is, with the support members 32, 32&#39; detentedly received within the cutouts 58, 59, respectively, and with the upper shank portion 22 rotated into overlying abutting relation with the lower shank portion 21, there is provided a folded anchor 10, with an overall folded dimension, on the broader side, approximately equal to the length and width of the fluke assembly 30 or 30&#39;, and on the narrow side, generally within the face dimension of the front or rear wa11 50a or 50b of the slide block member 50 (See FIG. 3). By way of example, and not of limitation, for an anchor 10 of approximately 17 pounds, these dimensions would be approximately eight inches by thirteen inches by four inches deep. 
     In the open position, the fluke assemblies 30, 30&#39; are in fixed relation to slide block assembly 40, with the shank pivot block members 54, 55 limiting the pivoting of the shank assembly 20 through an angle of +/-15 degrees relative to a plane through the plane of the web portion 45 of the shank retaining member 41. 
     In accordance with the present invention, there has been shown and described an anchor 10, of economical fabrication of plate steel, bar steel and tubular steel, to provide an effective anchoring means with the anchor 10 being capable of folding into a compact arrangement. Furthermore, the sole threaded fastener 75 employed in the structure, is captively retained and dimensioned to preclude complete removal of the nut 76, thereby minimizing loss of necessary parts in operation between the folded and unfolded positions. While there has been shown and described a preferred embodiment, it is to be understood that various other adaptations and modifications may be made within the spirit and scope of the invention.