Patent Publication Number: US-9834418-B2

Title: Boat deployment assembly and method

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application refers to and claims priority on U.S. Provisional Application Ser. No. 61/703,964 filed Sep. 21, 2012, the content of which is hereby incorporated by reference in its entirety. 
    
    
     BACKGROUND 
     The discussion below is merely provided for general background information and is not intended to be used as an aid in determining the scope of the claimed subject matter. 
     Undesired motion of an object being hoisted is quite common. Deployment and retrieval of boats from structures or vessels is one example. The hoisting of the boat can sometimes be quite difficult due to for example and without limitation motion of the vessel, turbulence of the water and/or wind loads on the boat to be deployed or retrieved. 
     SUMMARY 
     This Summary and the Abstract herein are provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary and the Abstract are not intended to identify key features or essential features of the claimed subject matter, nor are they intended to be used as an aid in determining the scope of the claimed subject matter. The claimed subject matter is not limited to implementations that solve any or all disadvantages noted in the Background. 
     Aspects of the present invention relate to hoists, where one embodiment of the invention is particularly advantageous for the deployment of boats or other items from a larger vessel at sea. 
     A first aspect of the present invention is a hoist system for lifting and lowering an object such as a boat, which includes a support structure, a support member supported by the support structure and a hoisting assembly. The hoisting assembly includes an attachment assembly and a set of at least three flexible members operably coupled to the support member and the attachment assembly to retract and extend the attachment assembly vertically relative to a reference axis. The hoisting assembly is supported by the support structure and configured with the support member so as to space apart the flexible members from each other, and wherein each flexible member defines an oblique angle with the reference axis parallel to the vertical reference axis. 
     In a further embodiment, the hoisting assembly includes a second support member supported by the support structure, a second attachment assembly and a second set of at least three flexible members operably coupled to the second support member and the second attachment assembly to retract and extend the second attachment assembly vertically relative to a second reference axis. In this embodiment, the hoisting assembly is configured with the second support member so as to space apart the flexible members of the second set from each other, wherein each flexible member of the second set defines an oblique angle with the second reference axis parallel to a vertical reference axis. The second set of flexible members is operably coupled to the second support member such that the second reference axis is spaced apart from the reference axis of the other set of flexible members. 
     Another aspect of the present invention is a method of lifting and lowering an object comprising: extending a set of at least three flexible members operably coupled to a support member, an attachment assembly and a hoist assembly to retract and extend the attachment assembly vertically relative to a reference axis, the hoisting assembly being supported by a support structure and configured with the support member so as to space apart the flexible members from each other, and wherein each flexible member defines an oblique angle with the reference axis parallel to a vertical reference axis; coupling the object to the attachment assembly; and deploying or retracting the flexible members by operation of the hoist assembly to lower or lift the object. 
     In a further embodiment, the method can further include extending a second set of at least three flexible members and operably coupled to a second support member, a second attachment assembly and the hoist assembly to retract and extend the second attachment assembly vertically relative to a second reference axis spaced apart from the attachment assembly, the hoisting assembly being configured with the second support member so as to space apart the flexible members of the second set from each other, and wherein each flexible member of the second set defines an oblique angle with the second reference axis parallel to a vertical reference axis; coupling the object to the second attachment assembly at a point spaced apart from the attachment assembly; and deploying or retracting the flexible members by operation of the hoist assembly to lower or lift the object. 
     In any of the systems or methods described above the following features can be included alone or in combination. For instance, the hoist assembly can comprise two hoist assemblies, each hoisting assembly controlling extension and retraction of one of the sets of at least three flexible members. If desired, the hoist assembly includes a hoist, or at least a drum, for each flexible member. In a preferred embodiment, the support members, which could also comprise a single support member for both sets of flexible members, is supported in a cantilevered manner from the support structure. 
     The attachment assemblies can comprise a connector that is detachable from the object. The connector can provide one or more degrees of pivotal freedom such as embodied as a universal joint or a spherical joint. 
     The hoist system commonly comprise a controller operably coupled to the hoist assembly to control deployment and retraction of the flexible members. In one embodiment, the controller stores data indicative of the attachment assemblies being at a different selected vertical distances away from corresponding support members, the controller configured to lower and raise each of the attachment assemblies and maintain the selected vertical distance. Using an interface, the controller can be used to train the hoist system by adjusting the height of the attachment assemblies individually for one or more objects the hoist system will be used for. The preselected positions and/or selected vertical distances between the attachment assemblies can be stored individually and accessed to control the hoist system automatically to adjust the positions of the attachment assemblies when commanded by a user interface. Similarly, it should be understood that the controller can have stored positions of the support member(s) relative to each other and/or relative to the support structure for one or more objects to be lifted. Again, the hoist system can be operated to obtain these positions during training, whereafter the positions and/or relative distances can be stored. 
     Aspects of the invention are particularly advantageous when the support structure comprises a vessel and the attachment assemblies are configured to connect to a boat at spaced apart locations on the boat. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  in a perspective view of a hoist system in a first position. 
         FIG. 2  in a perspective view of a hoist system in a second position. 
         FIG. 3  is a schematic illustration of a computer. 
     
    
    
     DETAILED DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENT 
     A hoist system is generally illustrated at  10  in the figures. The hoist system  10  includes a hoisting assembly  13 , herein exemplified as including one or more hoist assemblies  11 A and  11 B, used to hoist an object  12  using one, and in a preferred embodiment, at least two spaced apart attachment points on the object  12 , each attachment point having a plurality of elongated flexible members, preferably three elongated flexible members for supporting the attachment point. The hoist system  10  is advantageous in that the hoist system  10  can provide a measure of restraint for movement of the object  12  in up to six degrees of freedom. 
     Herein, the hoist system  10  is exemplified for hoisting a small boat  12  such as from a larger vessel  16 , illustrated schematically. In this embodiment, the small boat  12  is less likely to move during hoisting (i.e. suspended), be it deployment or recovery, where the movement of the small boat  12  is caused by but not limited to movement of the vessel  16 . It should be understood that aspects of the present invention are not limited to the embodiment shown in that the hoist system  10  can be used to hoist other objects such as but not limited to submersibles, unmanned vessels, and the like. Likewise, aspects of the invention are not limited to use on a vessel  16  or even at sea, but rather, can be used in any other application where restraint of movement of the object hoisted is desired. For instance, other applications are situations where the object, the hoist and/or the support structure  16  experiences wind loading, which can take place even on stationary support structures or support structures that move such as vessel  16  exemplified herein. 
     In the embodiment illustrated, the hoist system  10  includes two identical hoist assemblies  11 A and  11 B. Each of the hoist assemblies  11 A and  11 B are mounted to the vessel  16  or a support structure connected thereto. Each hoist assembly  11 A,  11 B includes a hoist or a plurality of hoists  20  (herein by way of example three hoists  22 A,  22 B and  22 C) to control a plurality of elongated flexible members, herein exemplified as wire ropes  24 A,  24 B and  24 C. The wire ropes  24 A,  24 B and  24 C extend from the drum(s) of the hoist(s)  20  and the remote ends are each connected to a load attachment assembly  28  used to engage (in this embodiment removably or detachably engage) the object  12  to be hoisted. In yet an alternative embodiment it should be noted, the hoist system  10  can include a single hoist with multiple drum(s) to control at least two sets of the plurality of elongated flexible members to provide two spaced apart lifting points for the object  12 . Likewise, a single hoist having multiple drums can be provided for each hoist assembly  11 A,  11   b . Generally, the load attachment assembly  28  includes a plate  29 , herein exemplified as a plate, to which the ropes  24 A,  24 B and  24 C are connected and a connector  31  attached to and supported by the plate  29 . The connector  31  can take many well-known forms such as but not limited to hooks, clasps, shackles and quick release mechanisms to name just a few. Except for the form of the connection between the connector  31  and the plate  29  as discussed below, the specific type of connector  31  is not pertinent to the present invention. 
     In the embodiment illustrated, each of the wire ropes  24 A,  24 B and  24 C are guided and supported by a corresponding pulley or sheave, herein  32 A,  32 B and  32 C, respectively. A support member  34  supports sheaves  32 A,  32 B and  32 C. In this embodiment, the support member  34  extends outwardly, preferably in a cantilevered manner, from vessel  16  being fixedly coupled thereto at least at one end. The support member  34  can be mounted in a stationary position on structure  16  or be movable relative thereto. For instance, one or both of the support members  34  can extend and retract such as in a telescoping manner or be pivotable. If desired, one or both of the support members  34  can move linearly, for example on rails, in any or all of three orthogonal axes oriented relative to the structure  16 . Depending on the type and/or extend of movement and/or the use of additional guiding sheaves if necessary for the flexible members  24 A- 24 C, the drums associated therewith may or may not move with the corresponding support structure. If desired, a single, cantilevered support member can be used to both sets of wire ropes in a spaced apart manner. 
     Each of the sets of wire ropes  24 A- 24 C is configured so as to provide support and moreover restraint to the corresponding plate  29  in multiple degrees of freedom. In the embodiment illustrated, the sheaves  32 A,  32 B and  32 C are configured on the support member  34  to which they are connected so that the wire ropes  24 A- 24 C extend downwardly about a vertical reference axis, herein extending through the plate  29 , where each rope defines an oblique angle  44  with the reference axis  40 , stated another way, an obtuse angle with the reference axis  40  below the attachment assembly  28  In an alternative embodiment, the hoist(s)  20  may be disposed above the object  12  to be hoisted without the use of sheaves so as to provide two sets of flexible members to provide two spaced apart attachment points for the object  12 . Typically, each of the sets of wire ropes  24 A- 24 C comprise three or more spaced apart individual ropes about the reference axis  40  so as to provide restraint of the plate  29  in six degrees of freedom; however, this is but one embodiment. In further embodiments, the number of ropes can comprise more than three and also the number of ropes used for each of the attachment assemblies  28  can be different. Likewise, it should be understood that the wire ropes may not be disposed at equal angular intervals about the reference axis  40 . 
     The connection of each of the connectors  31  to the corresponding plate  29  can be in a fixed manner or with a pivotal connection. The pivotal connection can allow rotation only about the reference axis  40 , or in a further embodiment, the connector  31  is joined to the plate  29  using a spherical type joint or its equivalent that allows pivotal movement about the axis  40  as well as pivotal movement about one or more axes perpendicular to axis  40  (indicated as axes  41  and  42 ), if desired. Such joints are well-known and can include by way of example a spherical joint or a universal joint, which provides two degrees of pivotal freedom, or in combination with a further pivot connection so as to provide the third degree of pivotal freedom. Use of a joint with such freedom of movement may be needed if it is desired that each of the ropes  24 A- 24 C connected to each plate  29  shares the load of the object  12  at that attachment point substantially equally (if the ropes  24 A- 24 C are disposed at equal angular intervals about the axis  40 ). 
     In a mode of operation, to lift or lower the object  12 , the hoist system  10  is typically configured and commanded so as to retract or extend all of the ropes in unison so that the spaced apart attachment points (e.g. represented by plates  29 ) move in unison and the object  12  does not change in orientation during hoisting. In the embodiment illustrated, each of the hoist assemblies  11 A and  11 B are operated in unison from a single command to lift or lower the object  12  from an operator interface panel indicated at  50  that provides an input signal to a controller  51 , that in turn instructs the hoist assemblies  11 A and  11 B to play out or retract the same amount of wire of each of the ropes for each attachment point. Nevertheless, if desired and if configured as such, the hoist assemblies  11 A and  11 B can be operated independent of each other if, for example, pitching of the object  12  is desired. Likewise, although typically each of the hoists  20  of each of the hoist assemblies  11 A and  11 B is operated in the same manner to play out or retract the same amount of rope for each attachment point so that the corresponding plate  29  maintains a fixed orientation, preferably orthogonal, to the reference axis  40  during lifting or lowering, if desired, each of the hoists  20  of each hoist assembly  11 A,  11 B can be operated independently from each other so as to change the position and/or orientation of the associated plate  29  relative to its corresponding reference axis  40  as desired. 
     In yet a further embodiment, one or more of the support members  34  can move on the support structure in unison or separately in any of the movements described above to change the position or orientation of the object  12  as desired. 
     Any number of load sensor(s) and/or displacement sensor(s) (linear or rotational) indicative of the object  12  and/or any part of the hoist system  10  can provide input(s) to controller  51  to control operation of the hoist system  10  and/or be rendered to the user via interface  50  as desired. 
     Individual operation of each of the hoists  20  of each of the hoist assemblies  11 A,  11 B may be preferred in order to train or calibrate the hoist system  10  to the object(s)  12  to be lifted. In particular, such calibration can include adjusting the position of each of the plates  29  for each of the hoist assemblies  11 A,  11 B relative to each other for the object  12 , or each of the objects  12  that the hoist is used for. Stated another way the controller  51  is operably coupled to the hoist assembly or assemblies to control deployment and retraction of the flexible members  24 A- 24 C, wherein the controller stores data indicative of the attachment assemblies being at a different selected vertical distances away from corresponding support members, by way of understanding. It should be noted the controller  51  can use other signals as the basis for the position of the attachment assembly  28  such as but not limited to the rotary position and number of revolutions of the hoists  22 A- 22 C. 
     For instance, depending on the mechanisms used to connect each of the connectors  31  to the object  12 , it may be necessary that one of the plates  29  of the hoist assemblies  11 A,  11 B is lower than the plate  29  of the other hoist assembly during hoisting. This relative position between the plates  29  can be stored in memory in controller  51 , for instance through interface  50 . Storing the relative position(s) allows the hoist  11 A and  11 B to fully retract the associated wire ropes  24 A- 24 C as desired such as equally. Then, when the hoist system  10  will be used to hoist an object  12 , the type of object  12  can be indicated (if needed) and the stored relative positions and/or relative distances can be retrieved from memory, where the hoist system  10 , in one embodiment based on a single command from the user using the interface  50 , automatically commands the hoists  11 A and  11 B (and movements of the support members  34  as described above) so as to obtain the desired relative position or in effect a vertical distance between the plates  29  (for example as reference with respect to each corresponding support member  34  for purposes of understanding but not necessarily as a basis for control), and/or orientation of the plates  29  commonly with feedback provided from suitable sensors based on one or a few commands from the user using the interface  50  based on information indicative of a stored preselected vertical distance difference between the attachment assemblies. Similarly, it should be understood that the controller  50  can have stored positions of the support member(s)  34  relative to each other and/or relative to the support structure for one or more objects to be lifted. Again, the hoist system can be operated to obtain these positions during training, whereafter the positions and/or relative distances can be stored. 
     Once the desired relative position and/or orientation of the plates  29  or attachment assemblies  28  has been obtained the controller  51  controlling the hoist assemblies  11 A,  11 B can be commanded to maintain the relative position and orientation during lifting or lowering of the object  12 . If desired, individual control of the hoist assemblies  11 A,  11 B of the hoists  22 A- 22 C during hoisting can also be provided. 
     The hoist system  10  is particularly well suited to maintain the desired orientation of a boat  12  so that movement of the boat  12  during lifting or lowering is minimized for longitudinal movements (parallel to a reference line extending between plates  29 , if maintained at the same vertical height, and parallel to axis  41 ) as well as for lateral movements (parallel to axis  42 ). Rotational movements of the boat  12 , in particular, roll (about a line parallel to axis  41 ), pitch (about a line parallel to axis  42 ) and yaw (about a line parallel to axis  40 , which in the embodiment illustrated comprises a vertical axis extending from the surface of the water) are also restrained. 
     In yet a further embodiment it should be noted that the hoist system  10  can comprise only a single point of attachment. In particular, the hoist system  10  can comprise one of the hoist assemblies (e.g.  11 A) in the various forms as described above that controls three spaced apart wire ropes  24 A- 24 C with the corresponding plate  29  attached at thereto. 
       FIG. 3  and the related discussion provide a brief, general description of a suitable computing environment for the controller  51  and/or interface  50 . Although not required, the controller can comprise computer-executable instructions, such as program modules, being executed by a computer  100 . Generally, program modules include routine programs, objects, components, data structures, etc., which perform particular tasks or implement particular abstract data types. Those skilled in the art can implement the description herein provided to computer-executable instructions. Moreover, those skilled in the art will appreciate that the invention may be practiced with other computer system configurations, including multi-processor systems, mini computers, computer on a chip, and the like. The invention may also be practiced in distributed computing environments where tasks are performed by remote processing devices that are linked through a communications network. In a distributed computer environment, program modules may be located in both local and remote memory storage devices. 
     The computer  100  illustrated in  FIG. 4  comprises a conventional computer having a central processing unit (CPU)  132 , memory  134  and a system bus  136 , which couples various system components, including the memory  134  to the CPU  132 . The system bus  136  may be any of several types of bus structures including a memory bus or a memory controller, a peripheral bus, and a local bus using any of a variety of bus architectures. The memory  134  includes read only memory (ROM) and random access memory (RAM). A basic input/output (BIOS) containing the basic routine that helps to transfer information between elements within the computer  100 , such as during start-up, is stored in ROM. Non-transitory computer readable storage devices  138 , such as a hard disk, an optical disk drive, ROM, RAM, flash memory cards, etc., are coupled to the system bus  136  and are used for storage of programs and data. Commonly, programs are loaded into memory  134  from at least one of the storage devices  138  with or without accompanying data. 
     An input device  140  typically included on interface  50  such as a keyboard, joystick(s), or the like, that allows the user to provide commands to the computer  100 . A display  142  or other type of output device can be connected to the system bus  136  via a suitable interface and provides feedback to the user. The command signals for the hoist assembly or assemblies can be provided, in part, based on program modules executed by the computer  100  and through a suitable interface  144  coupling the computer  100  to the test system rigs. The interface  144  can also receive feedback signals from load and/or displacement sensors embodied in the hoist system  10  as desired. 
     Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above as has been held by the courts. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.