Abstract:
A portable rowing device that in one mode can be attached to a boat to provide a muscle exercise by propelling the boat in a forward facing direction through a body of water or in another mode can be attached to an exercise stand to provide the same muscle exercise without propelling the user through a body of water.

Description:
FIELD OF THE INVENTION  
       [0001]     This invention relates generally to rowing devices and, more specifically, to a portable rowing/exercise device that in one mode can be used for exercise by working against a counter force or in another mode can be used for exercise by propelling a boat through the water in the direction the person is facing.  
       CROSS REFERENCE TO RELATED APPLICATIONS  
       [0002]     None  
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
       [0003]     None  
       REFERENCE TO A MICROFICHE APPENDIX  
       [0004]     None  
       BACKGROUND OF THE INVENTION  
       [0005]     In general, because of the known benefit of physical exercise those people whose jobs do not involve physical activity generally seek some type of regular exercise through an exercise machine. One such type of exercise machine is a rowing machine that allows a user to pull on two oar like members in a manner much as one rows a boat. Springs or weights resist the rowing motion and thus provide the user with an exercise workout as the oar like members are pulled toward the user. While such devices are an excellent way to provide exercise to certain muscle groups they confine a user to the exercise machine. The present invention in one mode comprises a portable exercise device wherein two portable exercises devices are mounted to the gunwales of a boat to enable the user to obtain the benefit of rowing exercise by paddling a boat through the water while facing in a forward direction direction and in another mode a portable exercise device that can be mounted to the rails of an exercise stand to enable a user to obtain the benefit of a rowing exercise during those conditions when one cannot be on the water.  
       SUMMARY OF THE INVENTION  
       [0006]     A portable rowing device that in one mode can be attached to a boat to provide muscle exercise by propelling the boat in a forward facing direction through a body of water or in another mode can be attached to an exercise stand to provide the same muscle exercise without propelling the user through a body of water. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0007]      FIG. 1  is a top view of a boat with portable rowing devices attached to the gunwales of the boat;  
         [0008]      FIG. 2  is a top view of the portable rowing devices attached to the sides of an exercise stand;  
         [0009]      FIG. 3  is a back view of the exercise stand of  FIG. 1 ;  
         [0010]      FIG. 4  is an exploded view of the drive mechanism of the portable rowing device; and  
         [0011]      FIG. 5  is a front view of a portion of the portable rowing device. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0012]      FIG. 1  is a top view of a boat  10  with a first portable rowing device  11  attached to the boat port side gunwale  15  and a second portable rowing device  12  attached to the starboard gunwale  16 . Boat  10  has a tapered or pointed bow  10   a  and a stem  10   b  and is propelled in the direction of the arrow D through use of the portable rowing devices  11  and  12 . A seat  17  is positioned proximate each of the portable rowing devices  11  and  12  to allow a user to operate the rowing devices  11  and  12  from a seated condition.  
         [0013]     Portable rowing device  11  includes a first gear  18  having a work arm  20  attached thereto with a paddle  21  located on the end of the work arm and a second gear  19  having a hand arm  22  with a hand grip  23  attached thereto. Similarly, portable rowing device  12  includes a first gear  25  having a work arm  26  with a paddle  27  located on the end of the work arm and a second gear  28  having a hand arm  29  with a hand grip  30  attached thereto.  
         [0014]     In operation of the portable rowing device  11 , a pulling motion on rowing device hand grip  23  (indicated by F 2 ) pulls the paddle  21  in the direction indicated by arrow F 4  thereby pulling the paddle  21  through the water which propels the boat in the direction of the bow arrow D as the rower faces the bow of the boat. Similarly, a pulling motion on rowing device hand grip  30  (indicated by F 1 ) pulls the paddle  27  in the direction indicated by arrow F 3  thereby pulling the paddle  27  through the water which propels the boat in the direction of the bow arrow D as the rower faces the bow of the boat.  
         [0015]      FIG. 2  shows a top view of the portable rowing devices  11  and  12  mounted on an exercise stand  30  having a left side rail  30   a  and a right side rail  30   b.  A seat  35  is mounted to exercise stand  30  to allow a user to sit thereon as the hand grips  30  and  23  are grasped and pulled toward the user in a rowing motion. A foot rest  38  allows the user to brace his or her feet thereagainst while pulling on the hand grips  30  and  31 . The portable rowing devices  11  and  12 , which are shown on boat  10 , are identical to the rowing devices shown on exercise stand  30  except the blade  21  has been removed from arm  20  and the blade  27  has been removed from arm  26 .  FIG. 2  shows the arm  20  has been repositioned at a right angle to arm  22  and arm  26  has been repositioned at a right angle to arm  29 . The repositioning can be obtained by rotationally repositioning gear  18  with respect to gear  19  and gear  28  with respect to gear  25 . Attached to end  20   a  of repositioned arm  20  is a first end  32   a  of resistance member  32 , such as a tension spring or the like, and similarly, attached to the first end  26   a  of repositioned arm  26  is the second end  32   b  of resistance member  32 .  
         [0016]     In operation of the portable rowing device in the exercise mode, as shown in  FIG. 2 , the rower pulls hand grips  23  and  30  in the direction shown by the arrows F 1  and F 2 . The pulling action causes arm  26  to pivot in a clockwise direction and arm  20  to pivot in a counter clockwise direction thereby exerting a pulling force on resistant member  32  thus causing the user to expend muscle energy as resistance member  32  is pulled from opposite ends. For example, if resistance member  32  is a spring one would expend energy elongating the spring or if resistant member  32  includes a set of weights one would expend energy lifting the weights.  
         [0017]     The portable rowing devices  11  and  12  are shown in a water propulsion mode in  FIG. 1  and solely in an exercise mode in  FIG. 2 ; however, in both instances the user performs the same rowing motion, namely, pulling the handles toward himself or herself against a resistance. The result is that the user has a year around exercise device that can be used outside in the summer time and indoors in the winter time to provide the same type of muscle exercise. Thus, regardless of where the portable rowing device is used one can provide the same exercise for the same group of muscles thus providing a continuity to the user&#39;s exercise program. In addition, when used on a boat the portable rowing device allows a person to face the direction the boat is being propelled as compared to conventional oars which require the user to face opposite the direction the boat is being propelled.  
         [0018]      FIG. 4  shows an exploded view of the operating drive members of the portable rowing device  11 . Gear  18  is rotatably mounted on a shaft  42  on pivotable base member  40  and supported by a washer  48  and  48   a.  Similarly, gear  19  is rotatably mounted on a shaft  41  and includes teeth thereon in meshing engagement with teeth on gear  18 . Washer  49  and  49   a  provide for rotational spacing of the gears on shaft  41  on pivotable base member  40 . A cover plate or shield  45  extends over the gears and is held thereon by screws  46  and  47  that are secured to shafts  42  and  41 . The cover plate can provide a finished appearance as well as prevent accidental access to the gears during operation of the portable rowing device  11 . One end of arm  22  includes a yoke having a central opening  22   c  for rotatable mounting on shaft  41  and a set of openings  22   a  and  22   b  for inserting pins  60  and  61  therein when the yoke is positioned around gear  19 . That is, the pins  60  and  61  extend through the openings  22   a  and  22   b  and through the openings  19   a  and  19   b  in gear  19  to affix the arm  22  to gear  19  thus allowing the user to rotate gear  19  by rotating arm  22  which in run rotates gear  18  which is in meshing engagement therewith. The arm  20  is attached to gear  18  in an identical manner and is not described herein. Consequently, the rotation of arm  22  produces a corresponding rotation of arm  20  through the meshing engagement of gears  18  and  19 . In the embodiment shown the gears  18  and  19  are of the same diameter; however, gear  18  and  19  can be replaced with gears of unequal diameter as long as the gears still mesh. By using gears of unequal diameter one can change the amount of force transmitted from the hand grip to the end of the work arm. Thus, the invention allows one to change the nature of the workout. For example, if the user decides that the work out is to light the gears can be changed to produce a new gear ratio that increases the effort to move the work arms against either the resistance regardless of whether the resistance is provided by the boat and water or by the resistance member connected to the work arms.  
         [0019]     Located below the pivotable base member  40 , which includes an opening  43  is a clamp  50  having a pivot pin  52  that extends through the upper part of clamp  50  and base member  43  to provide a pivoting support for the rowing device  11 . A washer  53  and cotter key  52  allow one to affix the pivot pin  52  into the U-shaped recess in the top portion of clamp  50 .  
         [0020]     Located on the lower portion of clamp  50  is an elongated slot having a pressure plate  56  with a slot  56   a  therein for engagement with a first thumb screw  54  and a second thumb screw  55 . The thumb screws allow one to removably fasten the portable rowing device  11  to the gunwale  15  through the clamp  50 . As the portable rowing device  12  as well as the fastening process is identical to portable rowing device  11  it is not described herein.  
         [0021]     With the base member  40  pivotally supported by clamp  50  the arms  22  and  20  are allowed to pivot in a plane extending longitudinally through shafts  41  and  42  while pulling on the arm  22  cause the arm  22  and  20  to move in a plane extending through gears  18  and  19  and perpendicular to shaft  41  and shaft  42 . Thus, the arm  22  can have an up down motion and a to an fro motion normally associated with an oar located in an oarlock on a rowboat.  
         [0022]     While portable rowing devices are shown mounted on opposite sides of both a boat and an exercise stand, if desired, only one portable rowing device could be used on either the boat or the exercise stand. For example, when used with a boat a rudder or the like could be used to steer the boat while the boat is propelled by a single portable rowing device  11 .  
         [0023]      FIG. 5  is a front view of a portion of the portable rowing device  11  showing the position of the base member  40  in the clamp  50  to allow for pivoting motion of the arms  20  and  22  about the pivot pin  51 . In the embodiment shown the arm  22  comprises an extendible member composed of tubular arm  22   a  having an opening  22   f.  The arm  22  includes a tubular member  22   b  and a tubular member  22   c  having a diameter dimension smaller than the interior diameter of tubular member  22   a  to allow for tubular member  22   c  to be inserted into tubular member  22   a.  A resiliently mounted pin  22   d  protrudes radially outward from tubular member  22   c  so as to engage the opening  22   f  when tubular member  22   a  and  22   c  are in engagement with each other to thereby lock member  22   b  to member  22   a.  It is envisioned that with the extension arraignment shown the length of arm  22  can be changed as well as the type of arm attached thereto. Similarly, the arm  20  is also extendible through identical members thus allowing extension or changing of the length of the members in the portable rowing device  11 .  
         [0024]     Thus the portable rowing device includes an attachment member or a support  50  for mounting the portable rowing device  11  on either a gunwale of a boat or on an exercise stand. A gear joined member having a work extension  20  on one end and an extension for grasping  22  on the other end forms a gear joined member including spur gears  18  and  19  which are in meshing engagement so that a rotational force on the end for grasping  22  causes the extension on the work extension  19  to rotate in a counter direction. In order to provide smooth and quite operation the gears can be made from non-metallic materials such as nylon or polymer plastics or the like that provide a cushioned contact while transmitting the rotational forces therethrough.