Patent Publication Number: US-9415979-B2

Title: High speed, reduced clearance lift

Description:
FIELD 
     This invention relates to the field of lifts and more particularly to a system for compact, high speed deployment from a watercraft. 
     BACKGROUND 
     There are many lift mechanisms in use today. Elevators are one form, lifting and lowering people and other loads, usually within buildings. Another form of lift is a hydraulic lifts that is used to raise vehicles in service stations, allowing mechanics to work from beneath the vehicles. Jacks are also lifts that raise vehicles allowing for changing of tires. The list continues, but in general, the lift mechanisms in use today make space/speed tradeoffs that limit usability in certain applications such as watercraft. 
     For example the hydraulic lifts used to hoist vehicles in your neighborhood garage performs well for its intended purpose, but will not perform well as a lift on a watercraft for several reasons. The first reason is speed. Such lifts are very slow. In many at-sea situations, there are often reasons for quick operation. It is often important to deploy a life raft or return a dingy to the deck and due to emergencies or high surf, the operation must be performed relatively quickly without precluding the use of a service station type of lift that often requires several minutes to lift an object eight feet. 
     The next reason why a garage-type lift will not function in a watercraft is vertical displacement. For example, to lift a vehicle eight feet, the hydraulic cylinder must be set at least eight feet into the floor, and likely at least ten feet. This is easily accomplished beneath the floor of a service station, but in many of watercraft, there is insufficient clearance between the deck of the watercraft and the hull of the watercraft. Many a watercraft do not have sufficient vertical displacement for a garage-type lift, especially in areas of the watercraft towards the bow where the hull slopes upward, closer to the deck, for cutting through waves. 
     The next reason why a garage-type lift will not function in a watercraft is weight. The overall weight of such a hydraulic cylinder and the hydraulic fluid needed to lift the requisite distance will be a burden to many a watercraft and even if the watercraft is large enough to support the weight, the excess weight will impact fuel economy and the ability to bring the watercraft up on plane. 
     Another reason why a garage-type lift will not function in a watercraft is stability. Such a lift operates well on stable ground, but in a watercraft, wave motion and winds create instability. When operating certain payloads on a garage-type lift within a watercraft, stability is often required. For example, when extending a hoist to lift a dingy out of the sea, sudden movement of the hoist due to movement of the lift mechanism is often disastrous. Certain movement results in damage to the dingy and/or sinking of the dingy. 
     Other lift mechanisms are not suited for watercraft for similar or different reasons. For example, elevators are not practical because such require overhead pulley systems which are not feasible on most watercraft. 
     What is needed is a lift system that will quickly deploy and retract a payload while occupying minimal vertical space and adding minimal weight to a vehicle such as a watercraft. 
     SUMMARY 
     In one embodiment, a high speed, reduced clearance lift system is disclosed including a lift platform and a lift frame for guiding and containing the lift platform. A telescoping hydraulic ram having at least three telescoping sections has a first end interfaced to the lift platform and a second end interfaced to a structural member such that, hydraulic fluid pressure introduced into the telescoping hydraulic ram forces the at least three telescoping sections to extend, thereby raising the lift platform into a deployed position, and abatement of the hydraulic fluid pressure allows the at least three telescoping sections to collapse, thereby lowering the lift platform to a retracted position. 
     In another embodiment, a method of deploying/retracting a payload from beneath a deck of a watercraft is disclosed. The method includes interfacing a first end of a telescoping hydraulic ram to a lift platform, interfacing a second, distal end of the telescoping hydraulic ram to a structure of the watercraft, and mounting the payload onto a lift platform. Fluid pressure is then forced into the telescoping hydraulic ram, thereby extending telescoping sections of the telescoping hydraulic ram and moving the payload from a retracted position into an extended position. Likewise, upon abatement of the fluid pressure, the payload moves from the extended position into the retracted position. 
     In another embodiment, a high speed, reduced clearance lift system for a watercraft is disclosed that includes a lift platform held within a lift frame. The lift frame guides and contains the lift platform and the lift frame is structurally interfaced to a hull of a watercraft. A telescoping hydraulic ram having at least three telescoping sections has a first end interfaced to a bottom of the lift platform and a second end interfaced to the hull of the watercraft. Hydraulic fluid pressure introduced into the telescoping hydraulic ram forces the at least three telescoping sections to extend, thereby raising the lift platform into a deployed position. Abatement of the hydraulic fluid pressure allows the at least three telescoping sections to collapse, thereby lowering the lift platform to a retracted position. Locking pin receivers are interfaced to the frame in a location where the lift platform rests when the frame is in the deployed position and locking pins are interfaced to sides of the lift platform, each of the locking pins actuated to removably engage with a corresponding one of the plurality of locking pin receivers when the lift platform is in the deployed position. The locking pins and locking pin receivers hold the lift platform steady during, for example, rough seas. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention can be best understood by those having ordinary skill in the art by reference to the following detailed description when considered in conjunction with the accompanying drawings in which: 
         FIG. 1  illustrates a perspective view of the moving components of the high-speed, reduced clearance lift. 
         FIG. 2  illustrates a schematic view of the high-speed, reduced clearance lift with the payload deployed. 
         FIG. 3  illustrates a schematic view of the high-speed, reduced clearance lift with the payload retracted and stowed. 
         FIG. 4A  illustrates a perspective view of a watercraft having the high-speed, reduced clearance lift with the payload retracted and stowed. 
         FIG. 4B  illustrates a perspective view of a watercraft having the high-speed, reduced clearance lift with the payload deployed. 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to the presently preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Throughout the following detailed description, the same reference numerals refer to the same elements in all figures. 
     Throughout the description, a crane  50  is used as an example of a payload  50 , but there is no limitation to any particular payload  50 . Any conceivable payload is anticipated, especially high energy payloads, transmitting forces in any axis. Some anticipated loads include hoists, cranes, cargo, vehicles, arms, etc. Additionally, in some configurations, the payload  50  is not attached to the lift platform  10 , for example when moving cargo in or out of the hull of a watercraft. 
     Referring to  FIG. 1 , a perspective view of the moving components of the high-speed, reduced clearance lift is shown. In this example, a high-speed, reduced clearance lift platform  10  is attached to deploy/retract a crane  50 , which is an example of a particular payload. Again, it is noted that many other payloads are anticipated. 
     The high-speed, reduced clearance lift includes moving portions such as a lift platform  10  and stationary portions that are held to a structure such as the hull  6  and/or deck  4  of a watercraft (see  FIGS. 2 and 3 ). In  FIG. 1 , the payload  50 , which is shown as a crane  50 , is supported by an optional rotary bearing that is bolted to the lift platform  10  so that the payload (crane)  50  is movable, for example, in an arc after the payload  50  is deployed as shown in  FIGS. 2 and 4B . Hydraulic and, optionally, electrical connections to the lift platform  10  and/or to move and operate the payload  50  are made through bendable cables  12  that bend when the lift platform  10  is retracted and deployed (as shown in  FIGS. 3 and 4A ). 
     The lift platform  10  is deployed and retracted by way of a telescoping hydraulic ram  30 . A first end  32  of the telescoping hydraulic ram  30  is anchored to the watercraft by, for example, a base member  20 , affixed to the telescoping hydraulic ram  30  by a flange  22 . The base member  20  is, for example, affixed to the hull  6  (or sub-deck) of the watercraft by any mechanism known, for example, by mounting plates  24  that are affixed (shown with bolt holes) to either the hull  6  of the watercraft, to surfaces of the lift frame  66  (see  FIGS. 2, 3, and 4B ), or to any suitable structure of the watercraft. The lift frame  66  also serves to guide and steady the lift platform  10 , especially while transitioning of the lift platform  10  between a retracted position and a deployed position. 
     The upper, distal end (last segment  40 -see  FIG. 2 ) of the telescoping hydraulic ram  30  is connected to the lift platform  10  so that the lift platform  10  moves up/down (deploys or retracts) responsive to the segments  34 / 36 / 38 / 40  of the telescoping hydraulic ram  30  telescoping under hydraulic pressure or collapsing after abatement of the hydraulic pressure. 
     The telescoping hydraulic ram  30  is fabricated from multiple segments  34 / 36 / 38 / 40 . Three segments  34 / 36 / 38  are visible in  FIG. 1  and four segments  34 / 36 / 38 / 40  are shown in  FIG. 2 , though any number of segments  34 / 36 / 38 / 40  (at least two) are anticipated and included here within. As is understandable from the drawings (see  FIGS. 2 and 3 ), by having segments  34 / 36 / 38 / 40 , the length of the telescoping hydraulic ram  30  in the compressed state (see  FIG. 3 ) is approximately the length of the tallest segment  40  (or the longest of the segments  34 / 36 / 38 / 40 ) and the length of the hydraulic ram  30  in the expanded state (see  FIG. 2 ) is approximately the sum of the lengths of the segments  34 / 36 / 38 / 40  (minus any overlap required for seals and retaining of the segments  34 / 36 / 38 / 40  to adjacent segments  34 / 36 / 38 / 40 ). Although the segments  34 / 36 / 38 / 40  are shown being substantially the same height, there is no requirement that the segments  34 / 36 / 38 / 40  are all the same height. The telescoping hydraulic ram  30  lifts the payload (e.g. crane  50 ) multiples of the collapsed height of the telescoping hydraulic ram  30 . This is an important feature, especially for watercraft, being that for many a watercraft; there is not sufficient head room (vertical space between the deck  4  and the hull  6 ) for a single-stage hydraulic ram. For example, if the payload  50  needs to be lifted 48 inches to clear the deck  4 , a traditional hydraulic ram (not shown) must be over 48 inches in its compressed mode, allowing the piston to travel at least 48 inches. This requires at least 96 inches between the deck  4  and the hull  6  plus additional depth for connecting and support. The 96 inches include the space below deck for stowing the 48 inch payload and 48 inches below that for the non-telescoping hydraulic ram. Many watercraft do not have this much distance between the deck  4  and hull  6 , especially when the hydraulic lift needs to be located close to the bow, where the deck  4  often approaches and/or meets the hull  6 . 
     The telescoping hydraulic ram  30  shown in  FIG. 2 , having four segments  34 / 36 / 38 / 40 , need only be approximately 24 inches high in order to raise the payload  50  by 48 inches. 
     The telescoping hydraulic ram  30  is provided with hydraulic pressure from a hydraulic pump (not shown) that is often already present on many a watercraft or from a separate hydraulic pump (not shown) or both. In some embodiments, hydraulic pressure is routed to the telescoping hydraulic ram  30  through bendable conduit  12  to accommodate the lifting and lowering of the lift platform  10 . 
     Because watercraft are not very stable and level, especially in rough seas, there are locking pins  14 , preferably located on each of the side surfaces of the lift platform  10 . In the example shown, there are four locking pins  14 , one on each side of the lift platform  10 . The locking pins  14  are retracted by actuators when the lift platform  10  (and therefore the payload  50 ) is in motion between the deployed and retracted positions, allowing the lift platform  10  to move upward or downward within the lift frame  66 . Once the lift platform  10  is positioned either in the deployed position (as in  FIG. 2 ) or in the retracted position (as in  FIG. 3 ), the locking pins  14  are extended outwardly from the lift platform  10  by actuators to engage within receivers  64 / 64   a  that are mounted on the lift frame  66 . The locking pins  14  are extended in any way known, including hydraulically, magnetically, motor driven, etc. It is preferred, though not required, to include a beveled interface between the locking pins  14  and the receivers  64 / 64   a  to compensate for tolerances in the positioning of the lift platform  10  within the lift frame  66 . Once the locking pins  14  are engaged into the receivers  64 / 64   a , the lift platform  10  remains stationary within the lift frame  66  without the need for constant hydraulic pressure within the telescoping hydraulic ram  30 . When the lift platform  10  and the payload  50  need to be moved (retracted or deployed), the locking pins  14  are retracted, for example, hydraulically, magnetically, by motor, etc., and are disengaged from the receivers  64 / 64   a    
     Referring to  FIG. 2 , a schematic view of the high-speed, reduced clearance lift with the payload  50  deployed is shown. In this view, the telescoping hydraulic ram  30  has been pressurized to expand the segments  34 / 36 / 38 / 40  and, therefore, deploy the payload  50  (e.g. a crane  50  with winch attachment  52 ). Once the telescoping hydraulic ram  30  has deployed the payload  50  (as shown), the locking pins  14  are extended and mate with the upper receivers  64 , securely holding the lift platform  10  (and payload  50 ) in the deployed position, at which time, in some embodiments, an abatement or lessening of hydraulic pressure provided to the telescoping hydraulic ram  30  is anticipated, being that the locking pins  14  extended into the upper receivers  64  are preferably designed with sufficient strength as to support the payload  50 . 
     In  FIG. 2 , it is shown how the first end  32  of the telescoping hydraulic ram  30  is secured to the lift frame  66  by attachment plates  22 , though any structural mounting scheme is anticipated. A hydraulic control panel  80  is also shown with controls for raising/lowering the lift platform  10  and for extending/retracting the locking pins  14 . There is no restriction on the type of hydraulic controls  80  and/or the location of the hydraulic controls  80  within the watercraft. 
     Although not shown, the lift frame  66  is secured to and supported by the hull  6  and/or the deck  4 , and/or any other structure of the watercraft, as needed for structural strength. 
     The payload  50  (e.g. crane  50 ) is shown deployed above the deck  4  and a cavity  8  is shown empty and ready to receive the payload  50  (e.g. crane  50 ) when the controls  80  are operated to release the locking pins  14  and retract the lift platform  10  and, consequently the payload  50 . In some embodiments, the cavity  8  has walls  68  to enclose the cavity  8  and reduce penetration of water from weather or waves that wash over the cavity and into the hull of the boat while the payload  50  is deployed. In some such embodiments, the cavity  8  has drainage or pumps to remove such water. 
     Referring to  FIG. 3 , a schematic view of the high-speed, reduced clearance lift with the payload  50  retracted and stowed within the cavity  8  is shown. The payload  50  (e.g. crane  50 ) is shown retracted below the deck  4  and stowed within the cavity  8 . As shown in  FIGS. 4A and 4B , it is anticipated, though not required, that doors  100  cover the payload  50  and cavity  8 , at least when the payload  50  is stowed beneath the deck  4 , reducing water intrusion into the watercraft hull area and cavity  8 . Once the lift platform  10  reaches the retracted position, the locking pins  14  are extended to engage with the lower receivers  64   a , securing the lift platform  10  in position supported by the lower receivers  64   a  which receive structural support from, for example, the lift walls  66 . 
     For payloads  50  that have arms that extend and retract (e.g. extend outwardly as the c 50  that is shown in the figures), it is anticipated that the arms of the payload  50  be retracted before retracting the lift platform  10 . In some embodiments, the retracting is automatic and required before movement of the lift platform  10  commences to prevent damage to the watercraft that would occur if the payload  50  is retracted while the payload  50  is in an extended position. 
     Referring to  FIG. 4A , a perspective view of a watercraft having the high-speed, reduced clearance lift with the payload  50  retracted and stowed is shown. In this view, the payload  50  (e.g. crane  50 ) is not visible, covered by doors  100 , and stowed below the deck  4 . Although not required, by including one or more doors  100 , when the payload is retracted  50 , the payload  50  is not visible and the doors  100  reduce water intrusion into the hull  6 . There are many ways anticipated for opening the doors  100 , including, but not limited to, motor or hydraulic drives (not shown), manual operation, and by the payload  50  pushing the doors  100  to the open position. Likewise, the same or different ways are anticipated for closing the doors  100  during or after retraction of the payload  50 , including, but not limited to, motor or hydraulic drives (not shown), manual operation, and by the payload  50  retracting, in which the doors  100  move to the closed position by tethers (e.g. attached to the lift platform  10 ) or by springs, etc. 
     Referring to  FIG. 4B , a perspective view of a watercraft having the high-speed, reduced clearance lift with the payload  50  (e.g. crane  50 ) deployed is shown. In this view, the doors  100  are open and the payload  50  is deployed. In this example using a crane  50  as the payload  50 , it is anticipated that the crane  50  is extended outwardly and/or rotated left/right to position the winch  52  over an object that is to be lifted in or out of the water or a dock, etc. In this view, the walls  68  of the cavity  8  are visible as is the top surface of the lift deck  10 . The walls of lift frame  66  are also visible. Note that the forward wall of the lift frame  67  is notched to allow for the payload to be lowered into the cavity  8 . 
     Although not shown, in some embodiments, vertical rails are provided and the lift platform  10  has orifices that engage with the vertical rails to steady the lift platform  10  during transitions between the retracted position and the deployed position. 
     Equivalent elements can be substituted for the ones set forth above such that they perform in substantially the same manner in substantially the same way for achieving substantially the same result. 
     It is believed that the system and method as described and many of its attendant advantages will be understood by the foregoing description. It is also believed that it will be apparent that various changes may be made in the form, construction and arrangement of the components thereof without departing from the scope and spirit of the invention or without sacrificing all of its material advantages. The form herein before described being merely exemplary and explanatory embodiment thereof. It is the intention of the following claims to encompass and include such changes.