Abstract:
An outboard motor lift is characterized by a lift assembly fitted to the transom of a boat and including parallel upper and lower links joining a bracket system attached to the boat transom with a motor mount bracket carrying an outboard motor, such that the outboard motor can move freely vertically up and down with respect to the transom responsive to contacting an underwater obstacle. Under circumstances where the outboard motor is heavy a spring system may be added to the lift assembly to offset the motor weight and facilitate vertical movement of the outboard motor by operation of the parallel links with minimal force when the outboard motor contacts the underwater obstacle. A handle coupled to another set of parallel links and a lift mechanism facilitate vertical adjustment and support of the lift assembly links and the outboard motor at selected operating positions. Since the outboard motor is positioned in spaced-apart relationship with respect to the transom, a throttle extension may be provided for comfortably operating the motor throttle when the lift assembly is in functional configuration.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application is a Continuation-In-Part of application Ser. No. 10/609,354, Filed Jun. 30, 2003. 
     
    
     BACKGROUND OF THE INVENTION  
     Field of the Invention  
       [0002]     This invention relates to devices for protecting foot, the lower unit and propeller of an outboard motor from damage due to shallow water running and/or collision with underwater obstacles and more particularly, to a lift assembly for mounting on the transom of a boat, wherein the outboard motor is allowed to move freely substantially vertically up and down with respect to a selected supporting position, responsive to contact with the water body bottom or underwater obstacles.  
         [0003]     One of the problems associated with outboard motors which are mounted in fixed position on the transom of a boat is striking underwater obstacles, which often causes damage to the foot, propeller and/or lower unit of the motor. Most outboard motors are equipped with a conventional lock/release device which facilitates kicking of the lower unit and foot rearwardly in an arc and tilting of the motor head forwardly about a point of pivot at or near the transom of the boat, to minimize damage due to such underwater collisions. Other devices are known which will cause a similar upward movement of the lower unit and foot of a motor at the point of pivot of the motor on the transom. All of these systems suffer from the disadvantage of requiring a considerable force to trip the latching mechanism holding the motor in a normal operating configuration, thereby increasing the likelihood of damage to the lower unit and/or the foot or propeller of the motor due to striking of the underwater obstacle. These devices also rely on adjustment locking features that must be manipulated to facilitate a change in the vertical positioning of the motor.  
       SUMMARY OF THE INVENTION  
       [0004]     The outboard motor lift of this invention is designed to allow shallow water operation of boats having outboard motors, without damaging the submerged motor components due to striking the water bottom and/or underwater obstacles. The outboard motor lift facilitates free, uninhibited upward movement of an outboard motor vertically upon striking an underwater obstacle, including a water body bottom, and return to a preselected support position. The device includes a lift assembly which is characterized by a transom bracket for mounting on the transom of a boat and parallel sets of upper and lower links pivotally attached to the transom bracket and to a motor mount bracket for fitting on a motor mount which receives and mounts the outboard motor. An adjustable support and handle/linkage combination is also provided for supporting the links in a desired pivoted position with respect to the boat transom, but allowing free up and down movement of the links and the motor from the selected adjustable point of support. Accordingly, the outboard motor is allowed to freely move or “float” vertically from the selected point of support, under circumstances where the lower unit, propeller or foot strikes the water bottom or an underwater obstacle while the boat is moving, and then to drop back onto the support. The relative position of the outboard motor with respect to the transom of the boat is adjustably determined by the handle and cooperating handle mount and linkage support apparatus while the boat is still or running. The linkage support apparatus contacts the underside of the bottom set of parallel sets of upper and lower links to facilitate adjustably positioning the outboard motor in a desired upward or downward position. In a preferred embodiment the handle is fitted with a grip lever and spring-biased lever cable, the latter of which connects to a pawl and pawl spring arrangement that selectively engages and disengages corresponding teeth in the handle linkage. This arrangement allows control of the handle with respect to the handle linkage assembly and the outboard motor under circumstances where it is desired to adjust the height of the upper and lower links and thus, the outboard motor, with respect to the transom of the boat. It is particularly important to note that the handle/linkage support assembly used for adjusting the height of the outboard motor with respect to the transom of the boat does not at any time latch or lock the lift assembly into the selected supporting position during operation of the boat. Rather, the handle and handle linkage/support apparatus is designed to support the parallel upper and lower links in a selected position, thus controlling the desired operational height of the outboard motor mounted on the lift assembly. Accordingly, at all times, the lift assembly and the outboard motor are permitted to move upwardly away from the supporting linkage/support assembly, should the skid or skeg, propeller, lower unit or foot of the outboard motor strike a submerged obstacle or the bottom, thereby minimizing damage to the outboard motor. Furthermore, a system of springs and associated cables may be provided in the lift assembly to apply upward tension on the lift assembly and offset the weight of the motor under circumstances where the motor is large and heavy. The spring or springs are sized such that the spring tension offsets the weight of the outboard motor and the force required to lift the outboard motor and lift assembly when the outboard motor strikes an underwater obstacle is minimal. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0005]     The invention will be better understood by reference to the accompanying drawings, wherein:  
         [0006]      FIG. 1  is a front perspective view of a preferred embodiment of the lift assembly of this invention with the attached outboard motor positioned in a partially raised configuration to support the outboard motor in a desired position with respect to the transom of a boat;  
         [0007]      FIG. 2  is a rear perspective view of the lift assembly illustrated in  FIG. 1 , wherein the motor is detached from the motor mount element of the lift assembly and the lift assembly is displaced downwardly with respect to the position illustrated in  FIG. 1  by operation of a control handle and linkage/support apparatus;  
         [0008]      FIG. 3  is a perspective view of a throttle extension which may be utilized to extend the throttle arm or handle of the outboard motor illustrated in  FIGS. 1 and 2 ;  
         [0009]      FIG. 4  is a side elevation of the outboard motor lift assembly and boat illustrated in  FIG. 2 , more particularly illustrating the lowered position of the lift assembly and outboard motor responsive to upward pivoting of the control handle;  
         [0010]      FIG. 5  is a side elevation of the motor and lift assembly illustrated in  FIG. 4 , more particularly illustrating upward movement of the outboard motor and the lift assembly with respect to the transom of the boat by upward pivoting of the handle to the position illustrated;  
         [0011]      FIG. 6  is a side elevation of the outboard motor and lift assembly illustrated in  FIGS. 1, 4  and  5 , more particularly illustrating free upward pivoting, or “floating” of the motor and lift assembly with respect to the transom of the boat responsive to striking of an underwater obstacle or the water body bottom by the foot or motor skid or skeg element of the outboard motor;  
         [0012]      FIG. 7  is a rear perspective view of the lift assembly illustrated in  FIGS. 1-6 , more particularly illustrating a typical normal operating position for the outboard motor, as illustrated in  FIG. 5  of the drawings;  
         [0013]      FIG. 8  is a front perspective view of the lift assembly illustrated in  FIG. 7 , more particularly illustrating the lift assembly in raised configuration for lifting the outboard motor responsive to striking of an underwater obstacle or bottom, as illustrated in  FIGS. 1 and 6  of the drawings;  
         [0014]      FIG. 9  is a partially exploded view of the motor mount and handle elements of the lift assembly illustrated in  FIG. 7  of the drawings;  
         [0015]      FIG. 10  is a partially exploded view of the upper and lower sets of links and the motor mount bracket system of the lift assembly illustrated in  FIG. 9  of the drawings;  
         [0016]      FIG. 11  is an exploded view of the transom bracket and optional spring and cable system for use in the lift assembly illustrated in  FIGS. 9 and 10  of the drawings; and  
         [0017]      FIG. 12  is an exploded view of a preferred control handle and handle mount assembly for effecting a desired vertical positioning of the outboard motor and the lift assembly illustrated in  FIGS. 1-11  of the drawings. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0018]     Referring initially to  FIGS. 1, 2  and  7 - 9  of the drawings, in a preferred embodiment the lift assembly of this invention is generally illustrated by reference numeral  15  and is designed for mounting on the transom  2  of a boat  1  ( FIGS. 1 and 2 ) to position an outboard motor  3  in spaced-apart relationship with respect to the transom  2 , as illustrated. The outboard motor  3  is typically characterized by a conventional propeller  4 , having propeller blades  5  mounted on a lower unit  6  and fitted with a downwardly-extending motor skeg  67 , as further illustrated in  FIG. 2  of the drawings. A conventional motor bracket  7  is provided on the outboard motor  3 , as further illustrated in  FIGS. 1 and 2  and typically includes one or more thumb screws  8  for tightening against the transom  2  of the boat  1  in a conventional mounting configuration. However, under circumstances where the outboard motor lift of this invention is utilized the motor bracket  7  is fitted over a motor mount  22 , having spaced-apart motor mount openings  23  that receive corresponding motor mount bolts  21  ( FIG. 9 ). The motor mount bolts  21  are designed to extend through the motor mount openings  23  and corresponding motor mount bracket openings  36 , provided in a pair of angled-iron motor mount brackets  35 , for securing to the motor mount brackets  35  by nuts  20 , as further illustrated in  FIGS. 8 and 9  of the drawings. In a preferred embodiment a channel-shaped center motor mount plate  37  is interposed between the two motor mount brackets  35  and is attached thereto by means of corresponding link mount bolts  42 . The link mount bolts  42  also serve to pivotally connect one end of respective pairs or sets of parallel upper links  26  and lower links  28  to the corresponding center motor mount plate  37  between the center motor mount plate  37  and the respective motor mount brackets  35 . The link mount bolts  42  are each typically secured by nuts  20  and extend through aligned openings provided in the motor mount brackets  35  and the center motor mount plate  37 .  
         [0019]     As further illustrated in  FIGS. 7-10  of the drawings, the opposite ends of the respective sets of upper links  26  and lower links  28  are pivotally attached to a center transom mount plate  17 , which is generally channel-shaped as illustrated. The outwardly-extending flanges of the center transom mount plate  17  are further provided with transom mount plate openings  18  ( FIG. 11 ) that align with corresponding transom mount bracket openings  53 , provided in the adjacent pair of transom mount brackets  51 . A transom mount bracket  52  spans the center transom mount plate  17  and the adjacent transom mount brackets  51  and acts as a mounting guide for the center transom mount plate  17 . Transom mount bolts  19  extend through transom mount bracket openings  53  in the respective transom mount brackets  51 , through the transom  2  of the boat  1  ( FIG. 2 ) to secure the lift assembly  15  on the transom  2  using corresponding nuts (not illustrated). In another preferred embodiment of the invention each of the parallel sets of upper links  26  and lower links  28  are fitted with a link spacer  29  ( FIG. 8 ) and the upper links  26  and lower links  28  are designed to facilitate free “floating” movement of the motor mount  22  up and down above a preselected, set supporting position, while the sets of upper links  26  and lower links  28  remain parallel to each other. Accordingly, under circumstances where the outboard motor  3  is clamped to the motor mount  22  as illustrated in  FIG. 1  of the drawings, the outboard motor is allowed to “float” up and down above an adjustable support element, by operation of the upper links  26  and the lower links  28 , to minimize damage to the propeller  4 , propeller blades  5 , motor skeg  67  and the lower unit  6  of the outboard motor  3 , upon striking of the water bottom or an underwater obstacle, as further hereinafter described.  
         [0020]     Referring again to  FIGS. 1 and 7 - 9  of the drawings, a lock bar  32  can be fitted to one of the lower links  28  by means of a link connecting bar bolt  34  and a corresponding nut  20  ( FIG. 10 ). Furthermore, the upper segment of the lock bar  32  is provided with vertically spaced-apart bar adjusting openings  33  for receiving a lock bar pin  31  that extends through a selected bar adjusting opening  33  and a corresponding link opening  30  provided in the upper link  26  ( FIG. 1 ), to selectively lock the travel of the upper links  26  and the lower links  28  for transportation and storage, when the lock bar pin  31  is not in use it can be inserted in a hole in a transom mount bracket  41 , as illustrated in  FIGS. 7-10 . As further illustrated in  FIG. 10  of the drawings, in another preferred embodiment, bearings or bushings  43  are seated in corresponding bearing or bushing openings  44  provided in the respective ends of the upper links  26  and lower links  28 , and washers  24  are interposed between adjacent bearings or bushings  43 , to reduce friction and facilitate ease in the parallel pivoting of the respective sets of upper links  26  and lower links  28  during operation of the lift assembly  15 . As further illustrated in  FIG. 10 , a pair of cable access openings  40  are provided in spaced-apart relationship at the bottom end of the center motor mount plate  37  for receiving a pair of spring cables  81 , fitted with cable stays  81   a  at the ends thereof and extending over a tensioning bar  85  and downwardly, to a pair of springs  80 . The tensioning bar  85  is typically mounted on the center transom mount plate  17  by a tensioning bar bolt  86  and a nut  20 . In a preferred embodiment of the invention the extending ends of the spring cables  81  are fitted with cable loops  88  for engaging the ends of the respective springs  80 , as illustrated in  FIG. 11  of the drawings. The opposite ends of the springs  80  from the spring cables  81  are attached to a spring mount bolt  87 , which extends through a selected one of a set of vertically spaced-apart tension adjustment openings  38 , provided in the flange elements of the center transom mount plate  17 , as further illustrated in  FIG. 11  of the drawings. In a preferred embodiment a series of spring mount spacers  82  are fitted on the spring mount bolt  87  adjacent to the flanges in the center transom mount plate  17 , to space the connected ends of the springs  80  from each other and facilitate proper tensioning of the springs  80  during operation of the lift assembly  15 , as hereinafter further described. The spring mount bolt  87  is secured in place in a selected one of the tension adjusting openings  38  by means of a nut  20  and is positioned in the appropriate tension adjusting opening  38  to facilitate a desired degree of tension on the springs  80 . This selected tension is commensurate with the weight of the outboard motor  3  which is mounted on the mount  22 , as further illustrated in  FIG. 1  of the drawings.  
         [0021]     Referring now to  FIGS. 7-10  and  12  of the drawings, in another preferred embodiment of the invention the lift assembly  15  is characterized by a handle mount  73  which mounts one end of a handle  78 , having a handle grip  77  at the end thereof. In a preferred embodiment a bifurcation  73   a  is provided in the handle mount  73  for receiving the top end of a toothed bar  69 , which top end is fitted with bar teeth  69   b , as further illustrated in  FIGS. 9-11  of the drawings. As illustrated in  FIG. 12 , the bifurcation  73   a  is typically covered at the top and bottom of the handle mount  73  by a pair of handle assembly plates  61 , fitted with corresponding plate screws  62 . The bifurcation  73  pivotally accommodates a pawl  89 , having a pawl spring  90 , for normally biasing the pawl  89  against the respective bar teeth  69   b  on the tooth bar  69  when the handle mount  73  is assembled on the toothed bar  69  with the top end of the toothed bar  69  extending into the bifurcation  73   a . A handle assembly bolt  60  extends through a corresponding pawl pivot opening  89   a  in the handle mount  73  and through a corresponding, aligned pawl opening  89   b  in the pawl  89 , for securing the pawl  89  pivotally inside the bifurcation  73   a . The handle assembly bolt  60  is typically maintained in position by a nut  20 . A handle mount bolt  71  projects through aligned handle mount bolt openings  76  in the handle mount  73  and through a tooth bolt opening  71   a  in the toothed bar  69 , to pivotally mount the handle  72  on the toothed bar  69 . A lever cable  79   a  extends from a cable spring  91 , secured to the pawl  89 , to a lever mount ring  84  and grip lever  79  assembly, which lever mount ring  84  is attached to the handle bar  78  of the handle  72 . Accordingly, depressing of the grip lever  79  tensions the lever cable  79   a  and the cable spring  91  and causes the pawl  89  to pivot on the handle assembly bolt  60 , disengage the corresponding bar teeth  69   b  provided on the tooth bar  69  and facilitate free rotation of the handle  72  about the top end of the toothed bar  69 . As further illustrated in  FIGS. 10 and 11  of the drawings, a stabilizing bar  68  is welded or otherwise attached to a spacer plate  65  in parallel relationship with respect to the toothed bar  69  and a bracket spacer bar  46  is welded to both the stabilizing bar  68  and the toothed bar  69 , to strengthen the toothed bar  69  responsive to operation of the handle  72 .  
         [0022]     Referring again to  FIGS. 7-10  of the drawings, the extending end of the handle mount  73  is fitted to one end of each of a pair of spaced-apart lift bar links  74  in the bifurcation  73   a  at the link bolt openings  72   a , by means of a corresponding lift bar link bolt  74   a , which also extends through the lift bar link openings  74   b , and is secured in place by a nut  20 . The bottom ends of the lift bar links  74  are similarly connected to a lift bar  70  by means of a link connecting pin  75 , which extends through the aligned lift bar link openings  74   b  in the bottom ends of the lift bar links  74  and through a selected one of three lift bar adjusting openings  59  in the lift bar  70 . Moreover, the top end of the lift bar  70  has a lift bar opening  70   a , for receiving a toothed bar bolt  69   a , that extends through a pair of washers  24  and an aligned bar opening  64  in the toothed bar  69 , for pivotally assembling the lift bar  70  on the fixed toothed bar  69 . Accordingly, pivoting of the handle  72  on the toothed bar  69  facilitates a corresponding pivoting of the lift bar link  74  with respect to the handle mount  73  and the lift bar  70  and raising and lowering of the lift bar  70 , for purposes which will be hereinafter further described. The lift bar  70  is disposed in parallel relationship with respect to a corresponding connecting bar  55  and is joined thereto by a pair of bar connectors  56 , as further illustrated in  FIG. 10  of the drawings. A lift sleeve mount  58  extends from the bottom end of the connecting bar  55  and is designed to removably receive a corresponding lift sleeve  57 , which is typically connected to the lift sleeve mount  58  by a mount pin  58   a  ( FIG. 10 ). The lift sleeve  57  extends beneath the parallel lower links  28  and manipulation of the arm  72  thus causes the corresponding lift bar  70 , connecting bar  55  and lift sleeve  57  to move up and down, thereby manipulating the sets of lower links  28  and upper links  26  upwardly and downwardly to adjust the height of the outboard motor  3 , as further hereinafter described. The three, spaced-apart lift bar adjustment openings  59 , provided in the bottom end of the lift bar  70  ( FIG. 9 ), receive the link connecting pin  75  ( FIG. 9 ) and facilitate adjusting the linkage of the bottom ends of the respective lift bar links  74  on the lift bar  70 . This adjustment also determines the range of motion necessary in the handle  72  on the toothed bar  69  to move the lift bar  70 , connecting bar  55  and the lift sleeve  57  upwardly or downwardly and thus, the adjustment of the parallel upper links  26  and lower links  28  to set the height of the outboard motor  3  with respect to the transom  2  of the boat  1 .  
         [0023]     Referring now to  FIGS. 1 and 3  of the drawings, in another preferred embodiment of the invention a throttle extension  10  is provided and includes an extension arm  11 , fitted on one end with an extension arm grip  12  and on the opposite end with an arm engaging sleeve  13 . The arm engaging sleeve  13  of the throttle extension  10  is designed to fit over the conventional throttle grip  9  on an outboard motor  3  which is so equipped, and a pair of upwardly-extending sleeve flanges  13   a  is fitted with an engaging sleeve tightener  14  to allow tightening of the arm engaging sleeve  13  on the throttle grip  9  of the outboard motor  3 . Consequently, manipulation of the extension arm grip  12  rotates the extension arm  11  and the throttle extension  10  as well as the throttle grip  9  of the outboard motor  3  and facilitates throttle control of the outboard motor  3 .  
         [0024]     Referring to  FIGS. 4-6 ,  7  and  8  of the drawings, under circumstances where the outboard motor  3  is to be positioned in a selected normal operating configuration, the handle grip  77  of the handle  72  is grasped, the grip lever  79  is depressed to extend the cable spring  91  and the handle  72  is moved upwardly to disengage the pawl  89  from the bar teeth  69   b  in the position illustrated in  FIG. 4 , and lower the outboard motor  3  by corresponding movement of the lift bar links  74 , lift bar  70 , connecting bar  55  and lift sleeve  57  downwardly. Since the pawl  89  is now again locked into a bar tooth  69   b  corresponding to the adjusted position of the outboard motor  3  by operation of the pawl spring  90  ( FIG. 12 ), the outboard motor  3  cannot move further downwardly, but is free to move and “float” upwardly, and then back downwardly to the adjusted point of support, if the propeller  4  or propeller blades  5  or the motor skeg  67  contact the water bottom or an underwater obstacle  50 , below the waterline  49  ( FIG. 6 ). Accordingly, referring again to  FIG. 6  of the drawings, under circumstances where the motor skeg  67  encounters the water bottom or underwater obstacle  50 , the outboard motor  3  is forced upwardly in a “floating” action, such that the motor skeg  67  easily bounces over the bottom or the underwater obstacle  50  and then returns by gravity to rest on the lift sleeve  57  ( FIG. 10 ) without damaging the propeller  4 , propeller blades  5  or the lower unit  6 , as well as the motor skeg  67 , of the outboard motor  3 .  
         [0025]     Furthermore, under circumstances where it is desired to facilitate an upward positioning of the outboard motor  3  to a new elevation such that the propeller  4  and propeller blades  5  operate more shallow than the position illustrated in  FIG. 4 , the grip lever  79  is again depressed to tension the cable spring  91  and the handle  72  is again manipulated downwardly to the position illustrated in  FIG. 5 , thus raising the lift bar  70 , the connecting bar  55  and the corresponding lift sleeve  57  and consequently, raising the parallel upper links  26  and lower links  28  to approximately a horizontal configuration, as illustrated. This position also facilitates “free floating” of the outboard motor  3  upwardly from the new resting position on the lift sleeve  57 , since the lift assembly  15  is not locked into position thereon, such that any encounter with a shallow sandbar, water bottom or an underwater obstacle  50  by the motor skeg  67  ( FIG. 6 ) will facilitate immediate upward movement of the outboard motor  3  by operation of the parallel upper links  26  and lower links  28 , without damage to the propeller  4 , propeller blades  5  or the motor skeg  67 .  
         [0026]     It will be appreciated by those skilled in the art that the above described upward and downward manipulation of the handle  72  can be effected both while the boat  1  is still and while it is running. A quick movement of the handle  2  in either direction in a short arc after depressing the grip lever  79  effects a desired lifting or lowering of the outboard motor  3  to accommodate a shallow water bottom, stumps, logs, sandbars and like submerged obstacles, as desired. Moreover, movement of the handle with extreme downward position raises the motor into a travel or stored position, such as the position illustrated in  FIG. 1 , wherein the lock bar pin  31  can be inserted in the aligned lock bar adjustment openings  33  in the lock bar  32  and the link opening  30  in the lower link  28 .  
         [0027]     While the preferred embodiments of the invention have been described above, it will be recognized and understood that various modifications may be made in the invention and the appended claims are intended to cover all such modifications which may fall within the spirit and scope of the invention.