Patent Publication Number: US-7721666-B1

Title: Hull-mounted line retrieval and release system

Description:
ORIGIN OF THE INVENTION 
   The invention described herein was made in the performance of official duties by an employee of the Department of the Navy and may be manufactured, used, licensed by or for the Government for any governmental purpose without payment of any royalties thereon. 

   FIELD OF THE INVENTION 
   The invention relates generally to the retrieval and releasing of floating lines from a floating vessel, and more particularly to a hull-mounted line retrieval and release system that can retrieve and capture a line floating at or near the water&#39;s surface and also release the line so-captured. 
   BACKGROUND OF THE INVENTION 
   A ship or other surface-floating vessel frequently must be able to deploy and/or retrieve a “line” (e.g., tow rope or cable, towed sensor array, mooring line, etc.) floating at or near the water&#39;s surface. For example, an autonomous ship/vessel is frequently deployed from a mother ship and recovered by a mother ship using a mechanism (mounted on the autonomous ship/vessel) that can automatically retrieve and release a line that is towed behind a mother ship. Given the prevalence of autonomous ships/vessels in the Navy, there is a need for a mechanism that can accomplish these tasks quickly and reliably. 
   SUMMARY OF THE INVENTION 
   Accordingly, it is an object of the present invention to provide a ship/vessel mounted system that can retrieve a line floating at or near the water&#39;s surface. 
   Another object of the present invention is to provide a ship/vessel mounted system that can retrieve and capture a line floating at or near the water&#39;s surface and also release the line so-captured. 
   Other objects and advantages of the present invention will become more obvious hereinafter in the specification and drawings. 
   In accordance with the present invention, a line retrieve-release system is provided for mounting on the hull of a boat. Jaws are coupled to the hull of the boat and face substantially aft relative to the boat&#39;s bow. The jaws are capable of movement between a partially open position and a fully open position. The partially open position defines the system&#39;s “line retrieve” position whereas the fully open position defines the system&#39;s “line release” position. A latch is coupled to the jaws and is biased to cooperate therewith in the partially open position to thereby define a first enclosed region bounded by the jaws and latch. The latch permits one-way entry into the first enclosed region when a force is applied to the latch from outside of the first enclosed region. A line catcher is coupled to the hull of the boat aft of the jaws. The line catcher combines with the jaws in their partially open position to define a second enclosed region adjacent to the first enclosed region and separated therefrom by the latch. The line catcher permits one-way entry to the second enclosed region when a force is applied thereto from outside of the second enclosed region. Actuator element(s) are coupled to the jaws to move them to their fully open position to thereby open both the first and second enclosed regions. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Other objects, features and advantages of the present invention will become apparent upon reference to the following description of the preferred embodiments and to the drawings, wherein corresponding reference characters indicate corresponding parts throughout the several views of the drawings and wherein: 
       FIG. 1  is a part perspective view and part schematic view of a line retrieve-release system attached to a boat hull where the system is illustrated in its ready-to-retrieve and line-captured position in accordance with an embodiment of the present invention; and 
       FIG. 2  is a part perspective view and part schematic view of the line retrieve-release system illustrated in its line released position. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Referring now to the drawings and more particularly to  FIG. 1 , a portion of surface-floating vessel hull is referenced by numeral  100 . By way of illustration the portion of hull  100  is the vessel&#39;s bow that sits just above and below the water&#39;s surface designated by the dashed line referenced by numeral  200 . While the illustrated embodiment of the inventive line retrieve/release system is mounted on the bow portion of hull  100  that is just below surface  200 , it is to be understood that this system could be mounted on other portion&#39;s of a vessel&#39;s hull without departing from the scope of the present invention. 
   The present line retrieve/release system has a support frame or housing  10  that is mounted to hull  100 . Housing  10  provides the support and mounting framework for the components of the line retrieve/release system used to retrieve a line (not shown) floating at or near surface  200  when hull  100  is moving in a forward direction that is indicated by arrow  300 . The term “forward” as used herein refers to vessel movement that leads with the bow portion of hull  100 . 
   An arm  20  is pivotally coupled to housing  10  using, for example, a pin  22  that allows rotation of arm  20  in a two-dimensional plane of rotation so that the combination of housing  10  and arm  20  define jaws. Arm  20  points substantially towards the rear of hull  100 , i.e., substantially opposite to forward direction  300 . Coupled to housing  10  is a spring latch  24  that is spring-biased to cooperate with (e.g., contact) arm  20  such that an enclosed line capture region  26  is defined by arm  20  and latch  24 . In the illustrated embodiment, arm  20  is C-shaped where defining its portion of capture region  26  to facilitate line release action as will be explained further below. Note that depending on the shape of arm  20  at capture region  26 , housing  10  could also define a portion of capture region  26 . In the illustrated embodiment, spring latch  24  is pivotally mounted to housing  10  using, for example, a pin  28  with spring latch  24  being spring-biased to contact arm  20  as shown. 
   Mounted aft of arm  20  is a rotating multi-arm spinner or paddle wheel  30  that spins in the same two-dimensional plane of rotation as arm  20 . More specifically, paddle wheel  30  is defined by a central hub portion  32  that is mounted to housing  10  via a pin  34  such that paddle wheel  30  can rotate or spin. Extending in a radial fashion out from hub portion  32  in the paddle wheel&#39;s plane of rotation are a plurality of blades or paddles  36 . While four paddles  36  are illustrated, the present invention is not so limited as more or fewer paddles can be used without departing from the scope of the present invention. Typically, paddles  36  are evenly spaced about the periphery of hub portion  32 . Each of paddles  36  can be concavely or C-shaped at one face thereof (as indicated by reference numeral  36 A) for reasons that will be explained later below. Paddle wheel  30  is sized/positioned such that each of the outer ends or tips  38  of paddles  36  can cooperate with the outboard end  20 A of arm  20  when a paddle  36  is aligned with arm  20  in its partially open position as shown. As a result of such paddle  36 /arm  20  cooperation, a capture region  40  is defined and bounded by housing  10 , arm  20 , latch  24  and paddle wheel  30 . Capture region  40  is aft of and adjacent to capture region  26  with the two capture regions being separated by latch  24 . 
   Briefly, when hull  100  is moving through the water in forward direction  300 , the force of the oncoming flow of water (designated by F 1 ) causes paddle wheel  30  to rotate in a counter-clockwise direction. The counter-clockwise rotation of paddle wheel  30  creates capture region  40  when a paddle tip  38  cooperates with arm  20  as shown in  FIG. 1 . However, when paddle wheel  30  is positioned such that no paddle tip  38  is in contact with arm  20 , an entry into capture region  40  is provided. For reasons that will be explained further below, paddle wheel  30  is inhibited from complete clockwise rotation but is permitted to partially rotate in a clockwise direction. To accomplish this, a one-way rotation lock  42  is coupled to housing  10  adjacent paddle wheel. From a functional perspective, lock  42  allows paddle wheel  30  to fully rotate in a counter-clockwise direction, but only rotate clockwise an angular distance defined essentially by the angular separation between two adjacent ones of paddles  36 . Accordingly, lock  42  can be realized by a simple spring-loaded lever cooperating with paddle tips  38  as would be well understood in the art. Lock  42  could also be configured to cooperate with other attributes (e.g., tabs, notches, etc.) provided on paddle wheel  30  without departing from the scope of the present invention. 
   A rotation sensor (“RS”)  44  is also provided to determine if/when paddle wheel  30  is not rotating. Rotation sensor  44  can be an electromechanical or optical apparatus without departing from the scope of the present invention. Briefly, during a line capture operation, paddle wheel  30  will cease rotation when a line is captured. Sensor  44  generates a signal “S” in response to such rotation cessation. As will be explained further below, signal S can be used to trigger manual or automated operations that ensure the retention of the line that was captured. 
   To direct an oncoming flow of water to paddle wheel  30 , a water deflector  50  can be mounted to housing  10 . Deflector  50  extends forward of paddle wheel  30  and away from hull  100 . Deflector  50  can also serve as the initial contact point for a line (not shown) that is to be retrieved by the present invention. 
     FIG. 1  illustrates the present invention in its “ready-to-retrieve” and “line capture” position. That is, in this illustrated position, the present invention is poised to retrieve and capture a line (not shown) when hull  100  is moving in forward direction  300 . To maintain the present invention in this position, rotational movement of arm  20  must be inhibited. By way of example, such rotational movement inhibition can be achieved with a spring-loaded lock mechanism  60  cooperating with arm  20  as shown. However, it is to be understood that such rotational movement inhibition could be accomplished in a variety of ways without departing from the scope of the present invention. 
   With the present invention in the position illustrated in  FIG. 1 , a line (not shown) can be retrieved/captured when hull  100  is moving in forward direction  300 . Specifically, when hull  100  is moving in forward direction  300 , paddle wheel  30  is driven to counter-clockwise rotation under force F 1 . A line (not shown) floating at/near water surface  200  and crossing the path of such forward movement is eventually engaged by housing  10  or deflector  50  depending on the depth of the line. As a result, housing  10  or deflector  50  facilitates the guidance of the line towards paddle wheel  30  where the line will engage a shaped face  36 A of one of paddles  36 . The continued counter-clockwise rotation of paddle wheel  30  (caused by the force F 1  of the oncoming water as well as the force of the line engaged by paddle wheel  30  as hull  100  moves in forward direction  300 ) causes the line to be admitted into capture region  40 . 
   As hull  100  continues in forward direction  300  with a line in capture  40 , the line will tend to be driven into the aft most portion of capture region  40  thereby inhibiting further counter-clockwise rotation of paddle wheel  30 . To insure the continual retention of the line under higher loads, the present invention is configured to next cause the captured line to be admitted into capture region  26  as follows. When paddle wheel  30  is no longer rotating in a counter-clockwise direction, signal S is generated by sensor  44 . In response to signal S, a boat operator or automatic boat control system slows the speed of the vessel in forward direction  300 . The resulting change in forward momentum causes (i) paddle wheel  30  to now rotate in a clockwise direction by an angular amount permitted by rotation lock  42 , and (ii) the captured line to tend to move towards capture region  26 . The partial clockwise rotation of paddle wheel  30  combined with the momentum change acting on the line in capture region  40  will cause the line to be pushed up against latch  24  and apply a force thereto indicated by force F 2 . As force F 2  overcomes the spring bias of latch  24 , the line is admitted into capture region  26  and latch  24  is biased back into contact with arm  20 . 
   To release a line retrieved and retained as just described, a simple release mechanism is provided to release the line retained in capture region  26 . An actuator  70  is coupled to lock mechanism  60  and also to arm  20  via a rod or cable  72 . Lock mechanism  60  is representative of any mechanism that can engage arm  20  to prevent rotation thereof and be disengaged from arm  20  to allow rotation thereof. Referring additionally now to  FIG. 2 , the release of a captured line will be explained. Hull  100  can be stationary or moving during line release. To begin the line release process, actuator  70  first acts on lock mechanism  60  to unlock or disengage it from arm  20  as shown so that rotational movement of arm  20  is no longer inhibited. Next, actuator  70  pulls on cable  72  to thereby rotate arm  20  in a counter-clockwise fashion until capture regions  26  and  40  are opened to no longer exist as shown in  FIG. 2 . In the illustrated embodiment, the C-shaped region of arm  20  that defines a portion of capture region  26  helps to push a line therefrom when arm  20  is rotated by actuator  70 /cable  72 . 
   Once a line has been released, the present invention is returned to its “ready-to-retrieve” position ( FIG. 1 ). This can be achieved by reversing the tension in rod/cable  72  so that arm  20  is rotated in a clockwise fashion. This process can also be aided or alternatively achieved by means of a spring  80  coupled to housing  10  and arm  20  as shown. More specifically, line release movement of arm  20  would place spring  80  in tension where such spring tension would then be used to return arm  20  back to its “ready-to-retrieve” position. Once back in this position, lock mechanism  60  could again be actuated by actuator  70  (or could be spring biased) to engage and lock arm  20  in its “ready-to-retrieve” position. 
   The advantages of the present invention are numerous. A floating line can be retrieved/released by a simple mechanism mounted on a vessel&#39;s hull. The present invention incorporates an enhanced line retention mechanism that insures a retrieved line will be retained until the line is to be released. The use of a spinning paddle wheel provides reliable line capture in the forward direction. The entry of the line into the mechanism is facilitated by the hydro-dynamically powered paddle wheel thereby eliminating the need for the line to exert a force to enter the capture region. 
   Although the invention has been described relative to a specific embodiment thereof, there are numerous variations and modifications that will be readily apparent to those skilled in the art in light, of the above teachings. It is therefore to be understood that, within the scope of the appended claims, the invention may be practiced other than as specifically described.